Discussion of OK KB2 accident

[chuter]

I started this thread so hopefully all the name-calling and speculation can be here, and the other thread can be more of a memorial thread.

From the witness account:
"The witnesses further reported that while on the downwind leg of the traffic pattern, the gyrocopter appeared to fly straight and level at an estimated altitude of 100-150 feet above ground level (agl). Near the midfield point, the gyrocopter suddenly pitched to a nose down attitude and subsequently impacted the ground. One witness reported that the gyrocopter descended with an approximate nose down angle of 60 degrees "while rolling left and right.""

That doesn't sound like a forward tumble to me. It sounds like he nosed over at 100+ ft and impacted nose first.
From that height it seems like he would have had time to tumble forward more if it was a bunt, IMHO.

I know witness accounts can be inaccurate, especially if they don't know much about gyros or what a bunt is.

[barnstorm2]

We know he made a modification by removing the HS.

Is there any chance this is the first 'test flight' after the modification?

[chuter]

I wish I could offer more info, but all I really know is what's been posted here, which doesn't really lead to a definite conclusion.

I don't know when he removed the stab.

I know he'd been talking about going back to the Bensen style tail and keel-mounted stab. I guess that's what he learned on and he said the stab in the prop wash kept him from swinging the nose up like I've seen birdy and Chuck B. talking about.

[Harry_S.]

Michael;

Pardon me for asking, but have you offered; have you been contacted to assist, or would you prefer not to be involved in this particular investigation?


Cheers

[chuter]

Harry,

I haven't been contacted. It happened so quick; I saw it on the news Sunday at 10:00PM, then I called Marty Weaver Monday morning about 9:30 on his cell phone to ask if he knew anything about it and he said they were at the scene doing the investigation at that time. I just let him go back to work there without asking any more questions.

Tuesday evening I went to the airport and all that was left was a spot of torn up sod.

Marty isn't saying much; I don't know if he is bound by confidentiality through his connections to the FAA, or just doesn't want to fuel speculation.

I think that out of our gyro group Marty was the closest to Kelly and this has hit him pretty hard.

[Mike Schallmann]

FWIW I looked up the word STUPID in the dictionary --It is not slang or noted as derogartory. It is defined as: lacking normal intelligence or foolish--Now IMHO this is a perfect definition of flying without a horizontal stab --

[chuter]

My personal view is that stabs are a good thing and any gyro I own will have one, and I recommend them to everyone; but there are people who can fly many hours without one.

Is it stupid for an old unicycle driver to leave the bicycle in the garage and ride the unicycle?

I don’t think Kelly could have been lacking in normal intelligence or foolish and progressed in aviation as far as he did.

We don’t even know for sure if not having a stab caused the accident or even contributed to it.

A stab wouldn’t have helped much if it was control failure.

[Mike Schallmann]

Geez -Ive been involved in Aviation in one form or another for over 50 years --from model airplanes ,control line ,free flight ,RC Helis and FW -Ive designed and built several RC Helis -including the rotor systems -- when I used to fly RC Heli I learned that a stab was important.

I've also been involved in full sized aircraft since the late 50's --including building several FW's as well as designing and building 3 gyros --all of which had large stabs--

In all of these years I think I may have learned a thing or two --but one thing I KNOW is that a stab is an IMPORTANT part of an aircraft--

To think that a stab didnt contribute to this accident --is like an Ostrich sticking his head in the sand!

Fall off a Unicycle you may get busted up but generally you survive -- Crash a gyro from altitude and generally you get busted up real bad --most often you DIE-- which would you choose!

[chuter]

If it was control failure how would not having a stab have contributed to it?

That would be like the unicycle driver getting hit by a truck and saying he should have been on a bicycle.

[giro5]

As posted in the other thread if the gyro was moving from side to side on its way down I think control failure of one of the control rods is likely. Although I have no real experience I did whack my cross control arm on the head once with the rotor hard enough to almost rip it loose from the control bar and the slop that created lead to almost not control of the rotor.

[j bird]

Check this out on "Stabs"

http://www.asra.org.au/L_Stability.htm

[chuter]

Does anyone know if the PRA Incident Response Team (I think that's what it's called) is going to look into this accident?

Is there an established procedure for communicating with the FAA and NTSB?

[Aussie_Paul]

Check this out on "Stabs"

http://www.asra.org.au/L_Stability.htm


Jay, I introduce every person enquiring about gyros, to that document.

Aussie Paul. :)

[Mayfield]

Hi Michael,

The PRA IRT can only support the NTSB when requested. We have no legal standing in any investigation. Our sole purpose, at this time, is to provide gyro specific info to investigators when requested.

Marty is the PRA IRT member in Oklahoma. I'm certain he is trying to learn anything he can. I'm also sure, if and when he can legally and morally do so, he will share what he has learned with appropriate folks.

We hope to someday put together a "lessons learned" data base for the community.

Jim

[Mike Schallmann]

Why do you think it would be control failure -- the movement of the gyro does not indicate control linkage failure --it is more like likely PIO/PPO -- KB2's are an unstable machine without a horiz stab -- I saw A guy get killed in Ken Brocks personal machine --initially it looked like he threw a blade but in reality it was a PIO/PPO event -with catastrophic consequences--

This statement by Jean Fourcade says it all "It is always possible to fly an unstable machine, but not for everyone. Even for a very good pilot an unstable machine is more dangerous than a stable machine."

[Dean_Dolph]

Just for the record; back in December I received a call that my caller ID said was the U.S. government. I thought, gee, what have I done wrong now?!!

It turns out that a gyro incident a few days earlier, that was reported on the Forum, was being investigated and this government person was looking for someone gyro knowledgeable since he said he didn't have any knowledge about gyros. He had found my name somewhere and called. I couldn't help him but I put him in touch with Mr. Mayfield.

So, it looks like the investigative teams (at least this individual) are trying to involve people that know what to look for in gyro incidents. I'm hoping this is a result of the PRA IRT being proactive and making the agencies aware that there is knowledgeable people available to help them. If that is the case then we should see a continued involvement by the PRA IRT but hopefully we won't see it often.

[chuter]

Jim,

Thanks for posting; I didn't know Marty was on the team.

Mike S.

I disagree for reasons posted in prior posts in this and the other thread, but neither of us knows for sure, so I guess we'll have to wait.

[Dean_Dolph]

I'm not sure of the details on the PRA IRT. But I think that, at one time, Jim was soliciting knowledgeable people to join the IRT with the idea that there would be people across the country that could respond to an incident.

Jim, could you elaborate?

[Chuck_Ellsworth]

There seems to be some differences in the opinions, beliefes, thoughts , in the gyro group.

We have this opinion:

" I have made a cognitive decision that I will not teach in any gyropnae unless it has a stabilizer or stablilator. Not that the RAF2000 without either is unsafe because we know there are quit a few pilots out there that have flown them without either/or for thousands of hours safely. But I am a firm beleiver that "TRAINING" is the key to successfully flying any aircraft, not just a gyroplane. "

And this:

" This statement by Jean Fourcade says it all "It is always possible to fly an unstable machine, but not for everyone. Even for a very good pilot an unstable machine is more dangerous than a stable machine."

Then there is a loss involving a stabless machine flown by one of the most skilled pilots in aviation, barring a mechanical failure or a medical problem does this not make one wonder who to believe regarding the need for an HS?

[chuter]

I’ve got a theoretical question.

A KB2 like Kelly’s was probably near CLT (seat tank, direct drive VW engine) so it may not have had a lot of ppo force.

If a gyro like that with no HS started oscillating in pitch, would it be possible for it to unload the rotors to the point of no recovery but not have the tell-tale signs of a bunt (rotor hitting the tail)?

[Timchick]

In another thread someone said this gyro flew a little nose down with the stab on it. I wonder if taking the stab off only made it worse.

[automan1223]

Ron,

I have flown more than 1 gyro. While I have zero time in a single seat. I have flown, successfully I might add a total of 6 different machines from old parsons, to almost stock raf 2000, to a full sparrow hawk, to an AAI Mod raf, and 2 different air command tandems, light and heavy. All gyros fly the same and yet they all fly different.

I have tons of video of rick abercrombies bensen, to daves thumper to Johns screwdriver, to the other daves bensen.

THEY ALL FLY NOSE DOWN !!!

http://jonathansautomotive.com/vdubbin.wmv
http://jonathansautomotive.com/vwmanrick1.wmv

maybe somebody can post tape of the screwdriver and photoshop the 2 images... ?

Now Johns might have had a few degrees more nose down would be hard to measure from a video..but this gyro nut thinks your time in the seat may be clouding your memory of just how a bensen or kb2 actually flies..... I am sure john and scott did a hang test and made sure the machine was in the window. comparing a Dominator to a KB is like apples and bananas.

now there is a pilot who took the hs off.. this complicates the matter but having less than 1 second to correct for a low g situation is a difficult thing to pin saving your butt all on training.... Like I HAVE SAID IN THE PAST...It is just that 1 TIME that will get you.... and thats it...That is why you dont fly a machine minus a HS and a HTL.....

Ron, I am not mad with you no reason to bicker... just take it easy on Johns and Scotts feelings. There is a time and a place.......No need to have an answer for everything.....The new owner I am sure did a hang test and made sure it was safe to fly......If he did not then how would you call yourself a "CFI". Wind, NO HS, other factors mechanical.. who knows, lesson learned. Do you best. Pray it is always good enough.

Just some thoughts....

Jonathan

[GyroRon]

Jonathan, I know you have flown a few gyros and know you have enough smarts to know that you do not have to own and fly a gyro for years to know if it flys a certain way.

I have never implied that John or Scott did not build that gyro properly. Just noting that it may have had some quirks that could be worth considering.

Your 100 percent right... it is common knowledge that when you buy a used gyro you should hang test it and verify it is in balance from flying it. I too wonder if he did this. According to GyroMike, Kelly- 170 to 180 lbs was significantly lighter than John - 210-220 lbs.

[GyroRon]

And to restate.... the gyro seemed to fly nose low at high speeds. I am talking about balls to the wall, absolute full blast fly-bys, the nose seemed very low. Thinking about what you said Jonathan, I think your right, seemed like Rick Abercrombies little VW Bensen did the same thing.... so maybe it was normal for that machine. Doesn't mean the nose flying low doesn't happen, just that it may be normal for these machines.

Here is some pictures of it while John still owned it. The in flight pics show it flying pretty level, the speed we were flying was probably around 55-60 mph.

I even threw in a couple I took while I was flying it not that they show anything other than I flew it and had fun in the process

[PW_Plack]

Jonathan,

The new owner I am sure did a hang test and made sure it was safe to fly......If he did not then how would you call yourself a "CFI".

A hang test would not reveal any aerodynamic changes, only CG changes caused by the loss of a couple pounds of H-stab.

As for the "CFI" comment, there are still CFIs who advise flying HTL machines without H-stabs, so I'm not sure the rating guarantees expertise in this area.

[gyrogreg]

Just to be sure there aren't misconceptions about the Hang Test. The hang test does not identify or assure stability or instability. Actually, whether a gyro is fying nose-down or not is not an indication of stability.

What does matter a lot (besides the dynamic stability a HS affords) is where the CG is located relative to the RTV in flight. No matter how a gyro hangs, the CG is still hanging directly under the hang point. That same gyro may fly nose down or nose up or completely level according to the static moments it is experiencing in flight. In a hang test, there is only one vector- the Rotor Thrust (hang) Vector - and that is guaranteed to be exactly on the CG during a hang test. In flight, there are three other moments acting on the gyro - propeller thrust moment, airframe aerodynamic moment, and HS moment. The combination of these is what is important to where the CG is relative to the RTV in flight.

When you hang test a gyro, you are not testing any of these other moments. One might possibly try to simulate these other moments on the airframe during a "hang test", and you could somewhat simulate the in-flight effects of these moments and how they affect the CG/RTV relationship. During the hang test:

- Push on the prop to simulate prop thrust. Push hard, the prop does!

- Push back and down or up a bit on the nose to simulate some airframe drag and/or enclosure/windscreen lift or down-lift effects. Push hard, the drag is almost as much as the prop thrust!

- Push down or up on the tail to simulate the lift or down-lift of a HS. Depending on the simulated prop thrust and airframe drag moments, push hard enough, up or down, to level the keel - this is what the HS should be doing!

While you are doing all this, notice where the CG (pilot's BB) is when applying all these othe airframe moments. The CG position relative to the RTV is dependant entriely on these other in-flight forces and moments - and the original location of the CG during the hang test has no real determination of whether the CG is still on the RTV or not - as it was during a standard hang test.

Another way of looking at this is that a HTL gyro (one without an adequately compensating HS to hold the airframe level) will certainly fly nose-low! But, you could also change the keel mounting angle to the mast and make that gyro appear to "fly level". The keel may be level, but, with the uncompensated HTL, the CG will still be behind the RTV.

How level the keel flies,and especially how it hangs, is a very poor indicator of it's stability - actually likely a misleading indicator! The value of the hang test is to initially assure that the cyclic pitch linkage in the control system is arranged so it has full fore and aft range to maintain the rotor disk angle at an approximate 9 degrees AOA while the airframe is at (whatever) deck angle it is going to fly. Normally, the designer probably mounted the keel so that the keel will fly level! But, if that keel does not, for some reason (a new and highly offset prop thrustline?), fly keel level as the designer intended, the pitch control linkages will not provide adequate fore/aft range as needed (for proper takeoffs, landings, recovery from high or low airspeeds, at different power levels, etc.)

The true mechanism designers (should) use to maintain the CG/RTV relationship in the stable condition is to balance all these moments acting on the gyro. The best tool to do this is to employ a HS that essentially does overpower, or at least "balance" all the other destabilizing (nose-down) moments and essentially holds the airframe level under all conditions of power and airspeed. Even then, put a heavier load in the front, and it may fly a bit nose-lower too. But, in this case, with the strong HS trying to hold the nose up, the CG is probably still at essentially the same relative stable location to the RTV as before.

An easy way to look at this is in terms of a very large and effective HS - mounted on a long moment arm (far aft)! It is easy envision that this overwhelmingly powerful HS will make the gyro fly keel level - no matter what. Now, if that gyro is loaded nose-heavy, but the HS still keeps the keel level in flight, now the CG is certainly forward of the RTV, and the gyro is assured to be statically stable (It is also assured to be dynamically stable because of this very large HS place far aft!). That same gyro may indeed "hang" very nose-low! And, if the designer can count on the keel always being level (and the rotor flying at it's normal 9 degrees disk AOA), there is actually little reason to even do a hang test on this gyro - because the designer already knows the angle between the keel, in-flight, and the rotor spindle angle - this is what determines the pitch control linkage/range - that can be set up on the ground without hanging!

(If the designer cannot count on the HS assuring the airframe is always level in flight, then a hang test is more necessary - but only to be sure the control linkage is right. This is why some designers might call for different hang angles than others - they know their keel flies at a different angle to the rotor AOA!)

Please don't be misled by the hang test - it is not a stability indicator or a stability determinate as it would be for a FW. Most gyros do not have a fixed wing or a fixed rotor! The in-flight CG location is not determined by the loading nearly as much as it is determined by the other aerodynamic moment factors in-flight.

- Thanks, Greg Gremminger

[Dale Young]

Not all do. My Gyrobee flys just a little nose high no matter how hard I push it.

[dabkb2]

Is there a way I can tell if the push rods are ajusted correctly?

[gyrogreg]

Not all do. My Gyrobee flys just a little nose high no matter how hard I push it.

Hi Dale,

Do you have a HS? Unless your keel is mounted at an unusual angle to the mast, you have a severe drop keel, or an extremely draggy rotor requiring a lot of disk AOA, I expect you do have a HS heavily embedded in the propwash with a significant downward AOI mounted alignment.

If my guesses are correct, you might have a bit more negative AOI on the HS than needed. I understand the standard Gyrobee is not significantly HTL, and the propwash on the HS may be holding the nose a bit higher than necessary. If this flight attitude is OK with you - you have adequate control range and can readily balance on the mains for landing and takeoff - it is not so bad to artificially hold the nose a little high with the HS. This would probably indicate the CG us being held a bit further forward when power is applied - more stable!- kind of like a LTL does with power applied.

The one thing that might not be desireable - if it is the HS holding the nose abnormally high - would be it probably has a big change in flight attitude from power on to power off - fairly large trimmed airspeed changes from power on to power off too. If my guess on the HS is correct, I might be tempted to reduce the HS mounting AOI to closer to keel level.

- Thanks, Greg

[dabkb2]

I have a KB3 with a Herron T tail. It flys keel level ,no problem, But I got a little slow on 1 of my landing's. I applied more power and set it down OK, but when I pulled the power back after setting it down my left wheel came back of the ground, so I pushed it back down with the stick, no problem. Do you think this is from the P factor or what. There was no wind

[gyrogreg]

Is there a way I can tell if the push rods are ajusted correctly?

The control rods are initially adjusted from the hang test - with the stick held centered fore/aft, the gyro should hang at the angle the designer prescribes.

But, this is only a starting point. This only assures there will be adequate control range - pitch and roll - to fly it - if everything is as per the designer's configuration otherwise. If you have mounted the keel differently, the head differently, using a different rotor, etc., these designer prescribed hang parameters might not work exactly. Obviously, if you are the designer and you don't thoroughly understand the issues, your inital adjustments might not allow full range for safe flight.

In any case, don't just hop in and go flying. Balance on the mains fiorst to note if the stick seems to be adequately centered to allow raising the nose to a takeoff and landing attitude - power on and power off. On first flight, do not fly too slow - you may not be sure there is adequate forward stick to allow recovery from a vertical descent or slow flight.

On first few flights, final tuning of the control rods should be done. This is simply adjusting the rods so the stick is where you want it in normal flight. For instance, in normal, S&L flight, the stick might be off to one side, or too far forward or aft for your comfort - or for full range of deflection. Simply make rod length adjustments to position the stick where you want it. For instance, if, in the air in S&L flight, the stick is one inch to the left and needs to also be two inches further forward to be centered in pitch range, on the ground, with the rotor head in a fixed position, make control rods adjustments to move the stick those amounts. Then flight test again! Make sure you have adequate control range to fly and recover from Vne and a vertical descent. Also, be sure you have stick adequate range at all power levels - in case your unblanced prop thrustline forces unusually high or low flight attitudes.

A word of caution. Always check the full travel range of the stick to assure there is no binding or limiting of the control range by the rod-end bearings. The range of the stick or rotor head should not be limited by the rod end bearings. The most common, and dangerous complication is when the rod end balls reach their limit of rotation and further force on the controls tries to simply bend or break the shank of the rod end bearing. At all positions of the stick - usually in the four extreme corners, you should still be able to rotate the control rods at least a bit to assure that the balls are not at the limit of their rotation. This is limited most often by the relative rotational position of the rod end bearings on each end of the rod - try rotating the rod end bearings relative to each other to extend the stick range so that these do not end up binding before the rotor head or joystick reaches it's normal limits. If you ever fatiqued a rod end bearing shank so that it broke in the air, your family and friends will have a bad day!

Always be sure the lock nuts on the rod end bearings are tight. If the rod end bearing shank threads are allowed to turn, instead of the balls, the threads could wear out and your family would have another bad day.

- Thanks, Greg Gremminger

[gyrogreg]

I have a KB3 with a Herron T tail. It flys keel level ,no problem, But I got a little slow on 1 of my landing's. I applied more power and set it down OK, but when I pulled the power back after setting it down my left wheel came back of the ground, so I pushed it back down with the stick, no problem. Do you think this is from the P factor or what. There was no wind

Sorry, can't speculate on the cause. Could have been holding a bit too much side stick, could have been the rapid change in engine torque, could have been a wheel or suspention bounce - I'm just not familiar with that machine enough.


- Greg

[Screw]

Screw-In

Sorry, I've been very busy here lately and haven't had much time or desire to comment. But there have been questions that I can answer.

1. I built the machine as best I could.

2. Balance wasn't an issue. Kelly new he had to re-hang and re-balance because of our differance in wieght. Tim posted pics and I have pics of Kelly flying, and there doesn't appear to be a balance issue.

3. Kelly is old school about stabs and that is (According to him) the main reason he didn't post here.

4. I feel terrible that someone has paid the ultimate price in something that I built. I have not been contacted by anyone in refferance to the accident, and I'm not sure how much I could help if they did.

5. Kelly has thousands our hours flying everything, and I sold him that gyro 2+ years ago.

6. I know he use to fly a stabless gyro before he got mine. I'm not sure he would have that big of a problem. However, every pic I have of him flying or otherwise, the stab was always there. Is it possible this was the first (or near first) time he flown that gyro without a stab?

Screw-Out

[chuter]

John,

No way is this your fault to any degree. Kelly was an A&P and kept the machine immaculate; I'm sure he would have seen any obvious deficiencies.

I can’t remember the last time I actually saw his gyro so I’m not sure when he removed the stab.

[C. Beaty]

3. Kelly is old school about stabs and that is (According to him) the main reason he didn't post here.
It is just possible that we have another example of Darwin’s theory of evolution: “survival of the fittest” at work here.

[Hognose]

[Note to all: I wrote this last week and left it on my laptop at work, never clicking Send. Sending now, even though this might be outdated info).

Once again, the investigation's preliminary report is here:

http://ntsb.gov/ntsb/brief.asp?ev_id=20070221X00207&key=1

While it is (as Ron Awad has suggested) consistent with a bunt, we don't know about a lot of things that are being investigated. It may have been medical incapacitation, it may have been another mechanical problem (rod end or control failure?), it may have been something else entirely. I hope that Martin and the investigators remain as open to the idea it may have been a bunt as I do to other possibilities. Gather the evidence, and the evidence will tell a tale if we're listening on the right wavelength.

I would like to know why the HS was not on the aircraft, and how long it had been off. It is true that some instructors (including Martin) believe and teach that it is not necessary. It also is true that Teague had a wide range of experience, including time in HS/HTL/no stab gyros.

On his website's gyro page, there are many photos of the mishap aircraft. All show it with the HS, which I believe was styled similarly to Ron Herron's T-tail but wasn't actually one of Ron's.

The page also shows Teague's self-described "first gyro," a no-stab Bensen Mac (rock guard is not a stab), and a no-stab standard-looking Bensen gyroglider.

It's deeply disturbing that a pilot with Kelly Teague's skill and experience should prang. I discussed this mishap last night with a flight crew training instructor with a major training activity; he's a guy with way more ratings than most of us, and more relevant college degrees than even ratings. He listened and said, "and you want to fly these things? Are you out of your [bleep]ing mind?"

I do not have Kelly Teague's flying skill or experience (10,000 hours!). I do not have my friend's years of advanced seminars in aerodynamics.

I want to understand how a skilled, safe, proven pilot in a thoroughly proven machine could come a cropper like this. So far as we know it was a mildly HTL machine, with no stab (why?), in gusty conditions, but flown by a man who had apparently flown many such in such conditions.

It's a very disturbing mishap.

cheers

-=K=-

[chuter]

The indicators of a bunt that are usually talked about don’t seem to be present in the evidence we have so far: the witness reports indicate it went nose-down at about a 60 degree angle and nosed in, there is no mention of it flipping over or tumbling.

Also, the witness reports did not mention hearing a bang followed by parts coming off the aircraft.

Chuck B, would it be possible to get into a PIO to the point of catastrophic unloading of the rotors but not have the rotors flap enough to hit the tail?

Looking at the pics it looks like it had a HTL at least to some degree. Could it be possible that it started a slow bunt since the HTL wasn’t extreme and he pulled all the way back on the stick so that the forward rotation stopped but he couldn’t pull up?

When I read the NTSB report about the stab not being on the gyro my heart sank and I could only put my head in my hands. My first thought was “Oh my god, why did you do that?”

But I have to take an honest look at what we have so far and there is no evidence that indicates a bunt other than he didn’t have a stab; that’s not evidence.

We could say that not having a stab increased the likely hood of getting into a bunt, but it’s not conclusive.

I know part of my uneasiness about this situation is the somewhat poor record the NTSB has with gyroplane accident reports; things like the tail rotor came off, etc.

[C. Beaty]

Michael, I only know of one presumed bunt where the rotor did not strike the vertical tail. That was at Dunnellon FL a number of years ago (NTSB Identification: MIA84FA112) In that case, the gyro was quite low and it smacked the ground before the rotor smacked the tail.

[Doug Riley]

"Bunt" is a vague catchall term whose exact meaning is unclear to me.

A power pushover typically causes retreating-blade stall. That (in a teetering rotor gyro especially) normally causes the rotor to contact some aft portion of the craft -- prop, rotor, even the keel. Evidence of such contact will be in the wreckage and usually in the witness reports. I investigated a PPO in which the rotor probably contacted the prop but didn't put a scratch on the rudder.

A torque-over is the equivalent of a PPO, but in the roll axis. A blade can stall, but it may not hit part of the gyro because there's not much to hit on either side.

It's possible on paper for a relatively sustained low-G event (or series of them, as in PIO) to result in so much loss of RRPM that the rotor flaps uncontrollably or even folds up.

In all three of these cases, the real telltale evidence is hammering of the teeter stops, bending of the hub bar and contact of the hub bar with other items on or near the rotor head. The hub may hit the torque tube/bar, the crossbar or prerotator components.

All three cases also result in loss of rotor thrust and hence control. Without control, you have to ask what caused the gyro to roll back AND forth as the witness account relates. A torque-over would be in one direction only; opposite the prop rotation.

Failure of a rod end from a manufacturing flaw would be easy for trained crash investigators to spot. Stripping of the rod ends out of their inserts, or fatigue failure, would, too.

I'm not in favor of taking the HS off a gyro. However, in the hands of an experienced "old school" gyro pilot, it should not result in a PPO out of level flight, wind or no wind.

[Chuck_Ellsworth]

Is it possible we should take a whole new look at this sport of flying gyros and treat them as the most dangerous flying machine to own and fly?

Then based on that assumption rethink how it is taught and why they are killing so many people both high time and low time?

Something is really strange in a lot of these accidents.

[Doug Riley]

Chuck, that's statistically correct. An honest instructor will tell his student this up front and let it sink in before starting training.

Whether the activity is mere Russian roulette (a game where the 1-in-6 probability of being killed can't be reduced) or whether something can be done to fix it is a much harder nut.

[Harry_S.]

"Bunt" is a vague catchall term whose exact meaning is unclear to me.


I'm not in favor of taking the HS off a gyro. However, in the ends of an experienced "old school" gyro pilot, it should not result in a PPO out of level flight, wind or no wind.



I'm in total agreement Doug...altho, I think you meant "in the HANDS of an an experienced "old school" gyro pilot."

Many years back when the likes of you, Chuck B, Tom M. Ron I, Ken B, Dick W, et al, were flying stock Bensens with the rock guard...not considered an HS...were having not too many problems, with stability, that is...the mention of a "bunt" was unheard of; PIO yes, PPO no.

IMO, modern day gyro pilots/enthusiasts are really concerned that a gyro, sans an HS is a death machine...is foremost in their mind. I don't believe this is true, but then...I'm of the old guard.


Cheers :)

[gyro]

I have not seen the pictures so I dont know what the craft looked like after the crash nor do I know what blades he was flying. But with all that is being said and reading the accident report is it possible that the teeter block came loose and cause the blades to ripple in the air?? this would explain the rolling back and forth and a sudden loss of lift.

[Doug Riley]

Harry, righty-o on "hands." I fixed it.

Bensens were a few inches HTL and most (well, mine anyway) were pretty low-thrust rigs. The PPO moment was there and it could kill you, but you had to aggravate the beast a little before it would bite.

The way you aggravated a Bensen into PPO-ing was to PIO it for a few cycles. Because of the exceptionally low rotor damping (high-RRPM, light blades) and the useless HS, the Bensen was easy to porpoise. Porpoise it a bit and it would go over.

Bensen didn't care; he was an engineering test pilot and was used to compensating for unstable rotorcraft. "Train for it; I did" was roughly his solution.

After Rotax redrives came out in the early 80's, the typical gyro accident changed. The longer, slower props made us move the engine on our Bensens (and clones) higher. Not knowing any better, we left the seats where Bensen had put them -- where you could reach the nosewheel to steer and drag your plywood board. Heavier and larger blades gave us more rotor damping, so PIO wasn't QUITE so bad, but these rigs would go over in a flash WITHOUT any preliminary PIO cycles. The fact that the bigger rotors and props made the machines perform better was fun, but added to the PPO risk.

A Brock-ish VW gyro like Kelly's is a throwback to those 70's gyros. We should look at this accident from that perspective, IMHO. They are reasonably flyable by an experienced pilot and generally don't PPO without at least a little provocation.

This is not one of our 1980's machines with 300 or 600 foot-pounds of PPO power. They are closer to the invisible edge of the cliff.

[RayPierce]

Michael, I only know of one presumed bunt where the rotor did not strike the vertical tail. That was at Dunnellon FL a number of years ago (NTSB Identification: MIA84FA112) In that case, the gyro was quite low and it smacked the ground before the rotor smacked the tail.
What about the Jamie Bodie, Sy Smith accident?
Was that considered a bunt?

[Dale Young]

Hi Greg, My Gyrobee does have a HS , But it is a VERY small one. I used a Sno-bird tail on it. Oddly enough, It seems as though it may have a slightly negative incidence to it. It always seems to fly at basically the same attitude ,with little change from cruise to nearly full throttle. Even when I dump power, It just gently noses over to a comfortable descent. I guess the setup just works well together. As Doug has informed me, It sure could use a bigger HS.

[Fl90]

Dale, if it's flying right for you, don't mess with it! Really, don't.

[C. Beaty]

A “bunt” is generally considered to be an occurrence where the airframe tumbles forward so fast the rotor can’t get out of the way.

[Hognose]

The accident that injured Bodie and Smith was not a bunt. It was quite a different beast. The Marchetti did not have enough control authority to raise the nose. Jamie was almost killed -- he spent two months in hospital -- and Si was also hurt. Jamie used to have the story and pictures on his website here:

http://portaparty.net/bodie/crash_page.htm

It's no longer there, not since 2005. It can still be found in the Internet Archive, albeit minus the images:

http://web.archive.org/web/20050424021722/http://portaparty.net/bodie/crash_page.htm

Here's a contemporary news story emphasizing the injuries to the two pilots.

http://www.timeswrsw.com/archive/1998/N0727985.HTM

Here is the NTSB statement of probable cause & synopsis:
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X10526&key=1

Money quote:

The previous owner said that the Vne of the gyroplane was 60 mph. At that airspeed, the gyroplane has a nosedown pitch of 5 to 6 degrees. The gyroplane had a 10-inch chord airboat propeller installed on it. The owner said that if the engine power is reduced below 1,200 rpm, the drag, induced by the propeller, increases on the aircraft and the nose will pitch down. The engine idles at approximately 600 to 650 rpm. 'If the aircraft was fast and the pilot reduced the power to idle, he would run out of aft stick.'

"Run out of aft stick," of course, is exactly what Jamie describes in his memory of the mishap.

Here's a 2003 thread where we discussed this mishap in the context of whether a Marchetti is good or not:

http://rotaryforum.com/forum/showthread.php?t=46

This mishap is a reminder that everything you change on an experimental aircraft can and probably will affect its flight characteristics -- and you might not like how. (like that 10 inch chord propeller). It's almost certain that it was this mod, and Si's unawareness of the downside of this mod, that bit them, rather than the Marchetti design per se.

cheers

-=K=-

[Brent_Brown]

The twinstarrs use a very wide prop. I see how this can happen but never hear anything like that with the Twinstarr. ?

[gyrogreg]

Hi Greg, My Gyrobee does have a HS , But it is a VERY small one. I used a Sno-bird tail on it. Oddly enough, It seems as though it may have a slightly negative incidence to it. It always seems to fly at basically the same attitude ,with little change from cruise to nearly full throttle. Even when I dump power, It just gently noses over to a comfortable descent. I guess the setup just works well together. As Doug has informed me, It sure could use a bigger HS.

Your "slightly" negative incidence HS may be well balancing the static prop HTL moments - reacting proportionately in the propwash to increased thrust (propwash). That would be good. That would explain the good Power Static stability you report. - BUT:

Dale, I agree with Doug - I would definitely want a bettter HS. The HS is THE dynamic dampener. Dynamic stablity is important. Dynamic stability, or instability, is the root cause of PIO! On such light short coupled gyros, the natural pitch rate can be extremely high. This means, without strong inherent pitch dampening, the machine can be excited into rapid pitching and/or rapid PIO. For such high dynamic rates, it is highly unlikely for a human pilot to be able to "dampen" the rate or oscillations. Most likely, if the pilot tries, his/her inputs will be to late - out of phase - and initiate a PIO or immediate "bunt".

It is starting to appear to me that it may be the lack of DYNAMIC dampening that is getting so many experienced pilots (not just a gyro's ability to buntover because the CG might be aft of the RTV) Even a small HS, so embedded in the propwash can be somewhat of a Dynamic dampener - but much more so when the prop is blowing on it! That means a PIO might even be more easily excited at lower power - especially lower power at high speeds where the aerodynamic moments on the airframe might be causing the gyro to fly too nose-down - CG aft of the RTV - G-Load unstable (more buntoverable!). The G-Load instability can also excite the pilot into just the wrong correction that might excite a dynamic PIO. If a gyro is going to have a natural high rate of un-damped pitch oscillation, it only takes the right sudden input or disturbance to "ring the bell", start the oscillation, like a certain note shattering a glass! You may never ever excite that oscillation, but the one time you do is probably the last!

IMHO, there is no subsitute for a HS that has enough dynamic power on it's own - not dependant on the prop blowing on it for it's dampening strength. And it's dynamic dampening effect not being so much a function of power. A HS's dampening strength can be improved with larger size, better airfoil shape for higher lift coeefficient, and further aft. If you want less change in dampening effect with power changes, it should not be too heavily embedded in the propwash!

Technically, you want enough dynamic dampening to create "critical dampening" of any pitch overshoot or oscillation. That means that if the gyro is excited into a sudden pitch movement, it will overshoot - past level - only once and just a bit, and it will inherently immediately return to steady state without additional oscillations about level! It is hard and/or dangerous to actually test if your dampening is "critical". IMHO, just b sure it is a s good as you can do. My suggestion is that, if the HS is adequately sized to provide good STATIC stability (per static flight testing), then, move that HS as far aft as practical, and you can probably count on superb dynamic dampening from that HS!

The "further aft" effect on a HS, for dynamic dampening effects, is even more helpful than just the moment arm enhancment for static stability. IMHO, there is also no substitute for a strong dynamic dampener than to be placed as far AFT as possible.

Why does further aft placement give a double advantage for the dynamic dampening aspects of a HS? Not only is the moment arm longer making all lift forces on the HS more effective, but the longer arm means the HS raises or lowers faster as a result of airframe pitching. This faster rate creates a higher AOA on the HS as the airframe is pitching - HS raising or lowering creating even more HS lift than just the mounted AOI. This part of the increasing AOA (lift) on the HS is at exactly the right phase to dampen the movement - greatest relative wind AOA and HS lift at the highest pitching rate portion of an osicllation! This precision phase effect is exactly what a HS can do automatically - and it can do that more powerfully if it is farther aft! But the pilot trying to correct for a high pitching rate may be out of phase and only tend to agravate PIO with the wrong, resonance phased inputs! The HS is guaranteed to put just the right dynamic phase pitch input into the gyro to dampen any pitching rate or oscillation - a pilot just cannot do that precisely when the rate is as high as it can be on such short-coupled light airframes! If the HS is a strong enough dynamic dampener, the pilot will not even sense pitching rates or oscillations that would even excite a pilot input - PIO - the gyro just stops ("dampens") the pitching rate or oscillation for you!

Just a hunch, but perhaps the difference between little or no dynamic dampening by a good HS may be the difference between life or death in some instances. When any pilot switches from a fairly well dynamically damped aircraft to one that is differently or less damped, it is very possible to get into trouble! Look at a FW pilot flying sedate GA airplanes - then getting into an aerobatic airplane and PIOing all over the place - at least until they get skilled at it. But, some light short coupled gyros just might have too high of a pitching or oscillation rate that a pilot cannot even learn to "dampen" it. And, I doubt they can learn how to do it the first time it happens suddenly!

There was an accident some years ago (in Texas I believe), where the long time pilot of a Dominator style gyro (strong HS dynamic dampening at most times - when power is applied). This pilot was used to a certain dynamic pitch response on his regular dynamically damped gyro. This pilot then built a KB. On first flight in the KB, in higher winds (where he had often comfortably flown the Dominator style), he PIOd and bunted over on the very first downwind! It is those surprises that hurt! It is not good to get into a different dynamically responding or damped aircraft - especially when you may not be anticipating anything to be different. When you "ring the bell" of PIO, natural, un-damped PIO, it may not be possible for a human to un-ring it! If I had any doubts about the dynamic dampening of a gyro I am flying, I would improve the HS!

Obviously, the SnoBird HS on your gyro, Dale, is not optimized for dynamic dampening!

Thanks, Greg Gremminger

[gyrogreg]

Someone in this thread suggested life or death in gyros might be a "roll of the dice"! I strongly disagree. If a gyroplane is approriately stable - including dynamically stable, it is not part of that crapshoot! Someone suggested there is a one in six chance of getting killed in a gyro - I strongly disagree! Look at the fatality rates - that identifies where the chances are that bad, and it identifies where the chances are much better!

IMHO, gyroplanes done right are so much safer than, and have so many realized safety advantages over FW or helos and other aircraft types! IMHO, what is killing people in gyros, in many cases, is simply that the pilot has not developed adequate proficiency to fly that gyro. In some gyros, it is just not possible to develop that profiency! Put together a pilot with inadequate proficiency in a gyro that a human can't become fully proficient in, we have an accident waiting to happen - just "ring the right bell"!

We all have choices: Either train and practice until we THINK we are good enough, or fix the gyro so we KNOW we don't have to be that good! I'd go for the assured thing! How do we know what the sure thing is - look at the accident results for one. If there are no buntovers or PIO incidents in a particular gyro, (maybe it has a very large HS?) maybe that is telling us something. If you don't believe the accident stats, then learn and believe in real aerodynamics and apply it! Or, gamble, and I don't like those odds!

- Thanks for your time. Fly safer! - Greg Gremminger

[chuter]

Dale,

In your picture it appears that the HS has POSITIVE incidence (front edge is higher than the rear edge).

This is not what you want in a HTL gyro; it will make it more statically unstable.

[Doug Riley]

Greg, in my response to Chuck Ellsworth, I said that, statistically, gyros are extraordinarily dangerous. That is history and fact.

Whether it tells us anything about the FUTURE is open to debate. It is not unreasonable from the evidence to conclude that Bensen-derived gyroplanes are INHERENTLY and INEVITABLY dangerous -- like Russian roulette. The probability of dying in Russian roulette is 1 in 6.

I'm not suggesting that the probability of dying in a gyro is the same number (it isn't, even statistically). It may be, however, that our crummy odds aren't improveable -- they are what they've always been, and we're stuck with them.

That, BTW, is exactly what the FAA and the rest of the aviation community think. That's why we don't have SLSA* while the entire rest of light aviation does.

IF the odds aren't carved in stone -- if we actually can make things better -- we have our work cut out for us. Some rather radical changes in our community's way of doing things are necessary.

What we have been doing up until now has not helped much at all.
___________________________________________
*Special Light Sport Aircraft = factory-made Sport-Pilot gyros.

[barnstorm2]

........That, BTW, is exactly what the FAA and the rest of the aviation community think. That's why we don't have SLSA* while the entire rest of light aviation does.

IF the odds aren't carved in stone -- if we actually can make things better -- we have our work cut out for us. Some rather radical changes in our community's way of doing things are necessary.

What we have been doing up until now has not helped much at all..

Exactly,

And that is why I actively post on the gyroplane stability issue.

People with unstable gyroplanes are not only killing themselves but also our sport.

I am not saying we know what happened in this case but as stated we know enough about what happens if only we could have only stable gyroplanes on the market and sufficent support and education for stablizing the machines already built.

PUT A STAB ON IT.

[gyrogreg]

Doug - well said. We need to keep trying to improve the acceptance within the community of concepts that at least improve the odds. I believe we DO know how to do it - I do beleive we do know how to improve the odds to negligible risk! Just getting everyone to believe and apply these things is the biggest challenge!

More and more, I just wish people would buy into a good dynamically damping HS. Air Command makes their new "Tripple Tail". I suspect that tail alone, or anything reasonably similar, would save life after life - on even the worst of today's gyros. That tail would probably turn a "gyro" into a "gyroplane" - and negative impressions into acceptance in the aviation community. It really is not Rocket Science! There may be other ways to stabilize gyros, but not many are cheaper and more inherently and passively effective as a good, big, airfoil shaped, HS placed well aft on the tail! And, that does not mean these dinky little, flat plate impersonations of a HS - put in the middle of the prop on the false assurances that would compensate for being so small and so ineffective! - are they doing better when the engine is not at normal power!!

It's just not difficult to put a good HS on the keel, where it can be large, far aft, and just as effective with and without the engine powered up!

IMHO, "gyroplanes" have the potential to be the safest sport aircraft flying by far! They won't stall, they land short and slow, they maneuver like crazy - With proper design they can go fast and slow very safely. With proper design, they can fly without concern or pilot workload in wind turbulence much worse than much larger aircraft would not venture into. With proper design, they would not roll over nearly as easily on the ground. With proper design they would NEVER PIO or PPO or buntover! With proper design, friends would not be dying! With proper designs, the sport would not be dying!

Chuter, you are also right. "People with unstable gyroplanes are not only killing themselves but also our sport."

I'm not implying any judgement on this latest accident - we need the full accident investigation to tell us things like whether the wreckage indicates a bunt or blade severe flapping, pilot experience in this gyro - with and without the dynamic dampener, aircraft logbooks to indicate when mods were made, etc.. How soon this accident happened after removal of the HS or not, might not be any proof of this accident. But it might be interesting circumstantial coincidence to find out if the pilot had been flying this gyro safely in similar conditions for a long time and there was suddenly a fatal accident soon after the removal of the dynamic dampener - even as meager as that dynamic dampener might've been!

- Greg

[Tina]

People with unstable gyroplanes are not only killing themselves but also our sport.


Be careful what you wish for that would mean restrictions on experimental aircraft do we really want that? I think we all are very lucky in America we have a lot of freedoms that other countries don't have. One is flying ultralights and building our own experimental aircraft what a freedom that is, that is what America is about. You put any kind of restriction on that and it takes away that freedom.

[Doug Riley]

Greg, Tina, the basic problem with the gyro community is cultural. Yes, there's such a thing as an unsafe culture as well an an unsafe piece of machinery.

"Experimental" should not mean guess-and-gosh, but it does in our world. People belligerently defend the "freedom" to be, and to remain, ignorant and to act upon their ignorance. They defend the right to teach their ignorant beliefs to others. They adhere to a nihilistic viewpoint -- one in which (1) there's no such thing as knowledge, only opinion, and (2) uninformed opinion ought to get equal weight with informed opinion.

We need more white-coated nerds with clipboards and pocket protectors. We need way fewer rodeo stars.

[JEFF TIPTON]

As an outsider looking into the gyrocopter circle I wonder if the gyro movement at this time is somewhere around 1910 to 1920 for the fixed wing world.

The ultralight and the experimental movement affords much opportunity to design your choice of aircraft. The early days enjoyed much freedom but with high cost to life. The Civil Aviation Authority was born which, a bad choice of words, dictated a design concept and training concepts called regulation. I see the gyrocopter movement at this stage of life.

It must learn how to break away from the perception that all gyro’s are unsafe. Many fixed wing pilots I talk to say they would never fly nor in a gyrocopter but they do not know what they are missing out on. The bad designs will remain around. Pilots will continue to die. The Federal Aviation Rules are written in the blood of our fellow aviators. We shall surely learn from their mistakes or we to will perish.

[aerodynamicdon]

Si has described the accident at length and with analysis. It's available on his site -PRA Instructors. The Cliff Notes short version: New wide cord blades were insufficiently internally supported= blade shape change=movement of the center of pressure=out of control rpm. Interesting reading. I look forward to training with him some more.

[bpearson]

I would bet that the unfortunate pilot in this accident knew all about current thinking on CLT and HS's. He lived in a country where he had a choice. Some of us live in regimes that make fitting safety to our machines or flying more stable designs near impossible. Be very careful about restricting individuals the choice to decide.

[Doug Riley]

Jeff, 1910 is about right. Some people were still doing lifting H-stabs and aft CG's on FW planes then.

For FW planes, WWI took us out of guess-n-gosh and into the world of methodical engineering. All the basics for low-speed airfoils and airframe design were in place by the early 20's. Anyone who was still eyeball engineering at that time was doing it out of foolishness or ignorance, not a lack of available knowledge. The Flying Flea and the primary gliders of the 30's are examples of "backwater" FW design -- design that didn't meet the state of the art, never mind advancing it.

Autogyro design in the Cierva era was just as numerical, professional and methodical as FW design.

However, today's gyros are analogous to the Flea and the primary gliders -- anachronisms that hark back to a pre-WWI state of knowledge (or rather lack of knowledge). We have a substantial contingent in the gyro world who do not WANT to know any more than they know right now. Hence we are stuck in 1910. Groundhog Day, in effect.

[barnstorm2]

Be careful what you wish for that would mean restrictions on experimental aircraft do we really want that? I think we all are very lucky in America we have a lot of freedoms that other countries don't have. One is flying ultralights and building our own experimental aircraft what a freedom that is, that is what America is about. You put any kind of restriction on that and it takes away that freedom.


Tina,

I am mostly libertarian in viewpoint and I want no more restrictions.

:director: However, if people keep flying these "BUNT-O-MATIC" gyro's we are going to get restrictions placed on us (or denied the freedoms of other experimental and light sport aircraft) if we like it OR NOT. :mad:

.

[Tina]

Tina,

I am mostly libertarian in viewpoint and I want no more restrictions.

:director: However, if people keep flying these "BUNT-O-MATIC" gyro's we are going to get restrictions placed on us (or denied the freedoms of other experimental and light sport aircraft) if we like it OR NOT. :mad:

. I think you are right to a point but all we can do is educate. My self I have learned a lot on what is safe and what is questionable and still am learning. I can also see a lot of good experts don't really know either they are still learning. To put any restriction on experimental aircraft says that is no longer experimental and our freedom is gone.

[Harry_S.]

:director: However, if people keep flying these "BUNT-O-MATIC" gyro's we are going to get restrictions placed on us (or denied the freedoms of other experimental and light sport aircraft) if we like it OR NOT. :mad:

.



Whoa, relax Tim.

I don't believe our movement will be sanctioned or denied any freedoms that we now enjoy. Anyway, negative rantings are not in our favor either.

If eventually, all gyroplanes are certified...there will certainly be fatalities...guaranteed.



Cheers

[Chuck_Ellsworth]

" If eventually, all gyroplanes are certified...there will certainly be fatalities...guaranteed. "

If gyros were certified they would have to meet set stability standards.

Now comes the next question Harry, if all gyros had to pass stability standards would there still be as many fatalities? :confused:

[barnstorm2]

Whoa, relax Tim.
I don't believe our movement will be sanctioned or denied any freedoms that we now enjoy. Anyway, negative rantings are not in our favor either.
If eventually, all gyroplanes are certified...there will certainly be fatalities...guaranteed.
Cheers

Gyroplanes have significant advantages over the other light sport and experimental aircraft.

Were it not for our safety record and "Don't fly one of those things, you'll get killed" stigma our sport would be VASTLY more popular than it is.

Every gyro accident causes us to loose more new pilots.

I am certainly NOT saying if all gyros were stable there would be no accidents.

However, if all gyros were stable we would have same or very possibly LESS fatalities then like aircraft.

Our sport is ALLREADY suffered and is suffering damage from stabless gyros.

You and I pay for this every time we go to buy a gyro part, or want a better gyro magazine or want a closer gyro fly-in or want to buy some professionally produced gyro videos or want to buy some 30 foot blades.

More people in the hobby mean more options, more business, more choices and cheaper prices and more to do. Period.

There is no reason our sport should not be as (if not more) popular then PPC's, PPG's, and Trikes other then our safety record. And our safety record is bad in very large part because of unstable machines and kit manufacturers that knowingly produce machines with flaws.

[barnstorm2]

Now comes the next question Harry, if all gyros had to pass stability standards would there still be as many fatalities? :confused:

And if gyros had to pass stablity standards would there be stabless gyros?

Would there be Mfg's selling flawed kits?

[gyrogreg]

Whoa, relax Tim.

I don't believe our movement will be sanctioned or denied any freedoms that we now enjoy. ---------------- Cheers

Harry,

I wouldn't bet on that! A little backgorund on FAA oversight!

A few years back, while I was working closely with the FAA on SP stuff, they came to me after the discouraging Utah fatal gyro accident with the question, what is the problem with gyros? I told them a lot of us think we know, but there are other opinions. I suggested they get opinions from both sides - they are not dumb - they knew all this! The "other side" was formally requested - at a sit down meeting at Oshkosh - to provide a report to the FAA. The "other side" did not provide the requested assessment.

To keep it objective, I (and some help from the forum) did an analysis on the NTSB reports to that time. That is basically the report you can find on the PRA site. The report we provided to the FAA had actual model identifications in it - but they asked us to leave out model names in the report we published in the magazine and on the WEB. (The posted report has Model A, B, C - etc.)

The FAA took this report to a meeting of Directorate heads. They came back and said, 5-10 fatalities a year didn't sound that bad! They asked us how many actual flight hours were involved in these accidents. Again, with the help of the forums and a lot of guess work, we estimated the total gyro flight hours per yearin the US (with a wide margin of error of around 3 to 1 - if I remember right.)

Anyway, when they saw the actual flight hours estimated, they were appalled! The fatality rate was several orders of magnitude out of acceptable bounds!

After emphasizing "something has to be done!", they asked what could be done - what would we, the gyro community and PRA recommend? The FAA said, if we don't do something to turn around that accident rate - THEY WOULD! They said, if they did something, we would not like it, and it would probably be the wrong thing anyway - but they would improve the fatality rate!

I suggested that we needed a gyroplane standard that addressed the main problems - specifically gyroplane flight stability. We were just starting into the ASTM process to develop LSA standards for the new rules. So, the FAA and we agreed that the gyroplane community would try to develop a gyroplane standard. The idea was that, with a credible "consensus standard", that defined criteria that would make gyroplanes safer, the industry and community would be encouraged to follow the guidance. Although the standard would not be regulatory - except for SLSA - it was thought that an accepted standard would put customer knowledge and market pressures to bring gyroplane safety along to the standard - even if it was not a regulatory requirement.

Essential to achieving a "consensus standard" was to involve the leaders in the gyroplane industry. I recruited a number of the BIG names in gyros to serve on the ASTM Gyroplane sub committee - including RAF, Air Command, Sport Copter, Ron Herron, Dominator, GBA, etc. Even though the FAA's Rotorcraft Directorate in Ft. Worth refused to help us ("these things are too dangerous for us to get involved!!!"), and even though no one in the FAA really thought the gyro industry could over come the deep internal squabbles - we did get an approved ASTM Gyroplane Design and Performance standard - consensus of everyone on the subcommittee and eventually the entire LSA Committee!!!!!

The FAA told us when this started that they hoped this approach would work - to lower the fatality rate - or they would "do something"! Almost right away, everyone took note of an improvement in gyro fatility rate - immediately. That was encouraging because we hoped it meant that just the publicity gyroplane safety and stability was getting was helping to educate and shape the gyro culture!

Since then, the fatility rate has back slid! Early on, the FAA told us they would go along with this "standard" strategy - but that if it did not work, the FAA would do something. This is why I have been publishing articles, explaining the standard and the technical principles, getting the PRA to encorse the standard, describing flight testing, etc. - so knowledge and acceptance and the culture change might stop these unnecessary fatalities!

Right now, I'm kindof waiting for the other FAA shoe to fall! Frankly, I'm almost ready for it! This has been a very discouraging struggle. And when I see continued old-culture pressures keep up with the mis-information and illogical arguments, I am just about ready to give up. I know how to fly gyros safely. I am helping others around me fly them safely. I'm just not sure we can really change this culture!

Don't be so sure the FAA will not do something - they are watching, I'm sure! This latest fatality, being one of their own and a very experienced pilot too, is just the kind of thing to get the FAA to step in! We need answers that hold at least some hope of remedy. I'm hoping we get them from a truly thorough and objective accident investigation and analysis. This is the first true test of the new PRA IRT team - I sincerely hope they are up to the need!

- Greg Gremminger

[Harry_S.]

" If eventually, all gyroplanes are certified...there will certainly be fatalities...guaranteed. "

If gyros were certified they would have to meet set stability standards.

Now comes the next question Harry, if all gyros had to pass stability standards would there still be as many fatalities? :confused:



Chuck...check the NTSB sites as regards the ongoing fatalities in certified aircraft. In reading them, I would guess that most incidents are due to "Pilot Error."

Who am I to say that IF gyroplanes were all to be CERTIFIED AIRCRAFT , fatalities would cease...come to a halt. That will never happen...we will continue to have falaities. Sad, but realistically, true.


Cheers

[Chuck_Ellsworth]

Harry:

It is my opinion that it as long as there is a mindset like yours the gyro group will continue to be looked upon as a fringe group of outsiders in sport aviation.

I do not blame Greg G. for getting discouraged, if I were him I think I would just walk away and let Darwinisim sort it all out.

To suggest that there would not be less fatal accidents if all gyros were designed and built to be stable is just plain incredible....in my opinion of course.....

[JEFF TIPTON]

The main objective of the kit manufactures and the LSA should be meeting the standards. Whether the machine has a stabilizer or not is not necessarily pertinent. They must meet a standard. There will always be bad machines. There will always be the individuals who want something a little different and that is part what the experimental classification is about.

For the true kits and LSA’s perhaps these manufactures should subject there machines to an outside committee that would evaluate the performance of the different designs and this would allow them to advertisement there machines as compliant. In this way the individuals would know with some certainty of the design.

Don’t be mislead. Even fixed wing aircraft, that I work on and fly do, have their models that do not perform up to everyone’s expectation. Cessna quit building the Cardinal because people said it did not fly like a Cessna. People do not fly the two seat Grumman because they claim it is squirrelly. This is the aircraft I learned to fly so I have some understanding what the pilots flying none stabilizer aircraft are going through.

In the end the truly bad and unsafe kits will disappear. The word will get out about them. This forum is good example of it.

To close accidents will always happen especially when we let down our guard and become complacent. Educating the members of the community is important. As for me< I have been flying since 1973 and only a Gyro once and that was with Greg at Shelbyville, and although I think I did pretty well for the first time I have not been that far behind the aircraft in a long time. I will definitely be looking for instruction before ever attempting that first solo.

[Harry_S.]

Were it not for our safety record and "Don't fly one of those things, you'll get killed" stigma our sport would be VASTLY more popular than it is.


THIS WAS THE SAME RHETORIC BACK IN THE 60-80'S.


Our sport is ALLREADY suffered and is suffering damage from stabless gyros.


TRAINING AND PILOT PROFICIENCY, TIM. CHECK THE NAMES OF THE OLD GUARD. MOST WERE SELF TAUGHT...WHY DO WE STILL LIVE?


There is no reason our sport should not be as (if not more) popular then PPC's, PPG's, and Trikes other then our safety record. And our safety record is bad in very large part because of unstable machines and kit manufacturers that knowingly produce machines with flaws.



Tim, you cannot discount PILOT PROFICIENCY.


Cheers :)

[Doug Riley]

I certainly agree with Greg that we deserve the FAA's boot on our throat.

I'm fed up with the belligerent ignorance of CFI's and manufacturers who live in some parallel intellectual world -- an Alice-in-Wonderland world where forces come and go when we blink, where forces travel around corners, where the equations for displacement, velocity and acceleration are a foreign language, where tailfins are dangerous and leaving them off is safe and WHERE CONTINUED IGNORANCE IS MORE "MANLY" THAN DAMN WELL GETTING OFF YOUR ASS AND LEARNING THE SCIENCE.

[TomCarlisle]

I think the myth of high time pilots being bullet proof is being proved wrong time after time and it makes it even worse on us when the paper or TV report it as "high time" or "very experienced" pilot. I know I tend to get complacent flying my Dominator and I consider myself a careful pilot. I make myself ask another pilot to pre-flight my machine at every fly-in I attend. Something is always found and I appreciate ANYONE noting something on my Dominator that doesn't look right to them. I have the choice to correct it or accept it as it is, but I never look down at anyone who asked why something is the way it is on my machine. It seems that High fixed wing-low gyro time is almost a cause of an accident in itself. I have a lot of total hours and relatively few gyro hours so I fly like every flight is my first solo. I hope I never get complacent in the Dominator.

[chuter]

AT least with this latest accident we know the result of the investigation won't be "lack of training".

[gyromike]

I certainly agree with Greg that we deserve the FAA's boot on our throat.

I'm fed up with the belligerent ignorance of CFI's and manufacturers who live in some parallel intellectual world -- an Alice-in-Wonderland world where forces come and go when we blink, where forces travel around corners, where the equations for displacement, velocity and acceleration are a foreign language, where tailfins are dangerous and leaving them off is safe and WHERE CONTINUED IGNORANCE IS MORE "MANLY" THAN DAMN WELL GETTING OFF YOUR ASS AND LEARNING THE SCIENCE.

Roger that.

[barnstorm2]

Tim, you cannot discount PILOT PROFICIENCY.
Cheers :)

I don't discount proficiency. I know that proficiency does NOT change the laws of physics.

I also know that if all gyros were stable we would have as good or better numbers then the other sport aircraft.

[chuter]

I was just looking at the NTSB database and found something interesting HERE. (http://www.ntsb.gov/ntsb/brief.asp?ev_id=20050811X01211&key=1)

It’s an Air Command 532 Elite.

“The make and model of gyroplane was known to be unstable, and the pilot was at least aware of a recommended upgrade kit to enhance stability, but had not installed it....”

“………A factor was the pilot's decision not to have a stability upgrade kit installed prior to flying the gyroplane.”

I’m guessing the NTSB made note of the known instability because Air Command has come out with their own “stability upgrade”.

Several other reports mention retreating blade stall.

Perhaps the NTSB is getting a bit more knowledgeable about gyros.

[reelmule]

I was just looking at the NTSB database and found something interesting HERE. (http://www.ntsb.gov/ntsb/brief.asp?ev_id=20050811X01211&key=1)

It’s an Air Command 532 Elite.

“The make and model of gyroplane was known to be unstable, and the pilot was at least aware of a recommended upgrade kit to enhance stability, but had not installed it....”

“………A factor was the pilot's decision not to have a stability upgrade kit installed prior to flying the gyroplane.”

I’m guessing the NTSB made note of the known instability because Air Command has come out with their own “stability upgrade”.

Several other reports mention retreating blade stall.

Perhaps the NTSB is getting a bit more knowledgeable about gyros.

Michael,
Don,t you think the pilot's decision to "self train" was at least as important or more important than the upgrade kit?Hell, with 5000hrs fw I knew that I would need alot of dual to "unlearn" the fw reflexes that get you killed in a gyro. I consider all 50 hrs of dual instruction money well spent. I'm sure that if I had decided to "self train" I wouldn't be making this post.
Walt G.

[chuter]

Don,t you think the pilot's decision to "self train" was at least as important or more important than the upgrade kit?

Walt,

Absolutely. I was just pointing out that the NTSB seems to be becoming more aware of gyro stability issues. Maybe that will lead to more realistic accident investigations.

[birdy]

Hmmmmm, just caught up with this thread after readn for over an hour.
Wot a wasted thread so far. :(
But its typical here, 6 pages of speculation.
And i can garantee one thing, if he hadnt touched the HS, this thread wouldnt have gon past 2 'sorry' pages.
But, apparently he had taken the HS off,[ why ill never know], and people blindly assume it was a ppo. And you say we ozzys are third world. :(
Its like sayn ol mate rolled his car coz he had old worn out tyres onit, but you never even see the broken drag link ball joint.

It seems most are blind to any other possability, BECAUSE HE DIDNT HAVE A HS at the time of the crash. As soon as its established that the machine isnt proper stable, stability is the only reason it crashed. Nuthn else could have caused it, no rod ends failed, no bearings seized, ol mate was in perfect health........, no, it was coz he didnt have a HS. Grow up.

You know my stance on stability, its no different to yours, but not every unstable gyro crashs coz its unstable.

Lets hope you pull your heads outa the stability sand and find out why ol mate crashed, and that he didnt die in vain.
Who knows, it could have been coz of the 'no HS', but i dout it.

I want to understand how a skilled, safe, proven pilot in a thoroughly proven machine could come a cropper like this. So far as we know it was a mildly HTL machine, with no stab (why?), in gusty conditions, but flown by a man who had apparently flown many such in such conditions.
Kevin, thats easy to explain. The hard part is accepting the reality.
Explination;[ its called reality]
Last year, australia's best, bar nun, race car drivers was killed.........raceing.
He was known as 'Peter perfect', coz of his smooth style, consistantsy, and almost umblemished and looooong race record and number of victories.
We all die eventualy, even the best, and not always do we get to choose how or wen. But wen you get out of bed in the morning alive, its no garantee youll be init tonight, or if youll wake up alive tomorrow.
Why did Perter perfect die do'n sumthn he was 'the' expert at????
We,[ or at least i] dont know for sure, but we gota go sum day.
If he got run over by a bus, its easyer to accept. We'd call it a horrible accident.
The reason why we find it hard to accept is coz of who died and how. He wasnt supposed to, coz he was the best, and we mistakeingly think the best dont make mistakes, or have a stroke of bad luck at the worst possable moment.
Its just not ment to happen.................... but like life, it dose.


One thing i am 100% sure of.
Wen i die, itll be because i dont have a stab on the ferel.:)
The fact that i die 100 miles from the machine, and my mangled body is found under a truck will have no relivace. ;)
Even if i am found in my machine, it'll be becaues it didnt have a HS.

[barnstorm2]

Michael,
Don,t you think the pilot's decision to "self train" was at least as important or more important than the upgrade kit?Hell, with 5000hrs fw I knew that I would need alot of dual to "unlearn" the fw reflexes that get you killed in a gyro. I consider all 50 hrs of dual instruction money well spent. I'm sure that if I had decided to "self train" I wouldn't be making this post.
Walt G.


If he decided to self-train in a stable CLT machine and he managed to figgure out rotor-management on take off he would most likely be alive right now.

I will NEVER condone self-training but the FACT is a stable gyroplane is safer, easyer to learn in and a CLT gyroplane would not have bunted.

[barnstorm2]

Birdy,

Myself and others have stated that we don't know if it was a bunt or not.

That does not invallidate the discussion of the detrimental effect of fatalites on our sport and the most common causes of those deaths.

[gyro]

I guess what I said about the teeter block got over looked but what about a possible heart attack...will an autopsy be done?

[Hognose]

I have read Si Smith's version of the accident here:

http://mentone98.8m.com/

The reason I didn't mention it before is simple: I never saw it before and didn't know it was there! It didn't come up in any of the searches I used. Check it out.

cheers

-=K=-

[pwongkit]

No,the http://mentone98.8m.com/ its not working:noidea:
pwongkit

[Friendly]

Birdy,
I agree with just because the man took off the stab it is not automatic PPO.
But the speculation of what could have happened does open the doors for a lot of beginners that there are several ways to have a fatal accident in a gyro and sometimes we forget those things and are reminded or we are further in the flying hours to where they make more sense.
You comments about experts are not suppose to die is very true in my opinion. If we newbies see the expert make mistakes, we often think , how in world can I do any better than him. I fly a KB2 and I was under the impression that it is a fairly stable aircraft.
I know that there are a number of possibilities such as pilot health,control rod failures, maybe loss of engine power during the downwind turn.
I don't think is was PPO because of some of the witness statements and C.B. comments about rudder strikes. Not everybody is saying unstable machine or no HS.
If something happens to you (God Forbid) we will have just as many pages to discuss the might have beens.
Oz is not a 3rd world country.

[birdy]

That does not invallidate the discussion of the detrimental effect of fatalites on our sport and the most common causes of those deaths.
Never said it did Tim, and its logical that dead pilots will give us a bad image.
However, sh1t happens, people have hart attacks, structual failures , altho rare, do happen.

Iv noticed too, that the average pilot age in gyros is quite high, alot of us are retired or are haven a second childhood. Flyn gyros is a very stimulating thing to do, and if your not prepared, it could be abit too much for the odd old bloke to handle.
Theres not too many of us older coots getn into drag racing or sumthn similar, but i recon that if we did, thered be a few 'unexplained incidents' there too.

Im not spectulating on this incident, im just tryn to keep peoples minds open.

Its stupid comment like this one;
To think that a stab didnt contribute to this accident --is like an Ostrich sticking his head in the sand!
Fall off a Unicycle you may get busted up but generally you survive -- Crash a gyro from altitude and generally you get busted up real bad --most often you DIE-- which would you choose!
that are pointless and damaging.:(
Mike, youd be one, with all the experiance you say you have, that i woulda thought would have had an open mind.
To think that a stab didnt contribute..............
Is that right?, and just how did you arrive at that very simple conclusion?
BTW, i smashed the ferel to pices only twice in my 15 or so misshaps, once with, and once without the HS, and iv never suffered even a scratch. [ admitedly not from ' altitude' but it wouldnt make that much of a difference.]
Mike is obviosly blinded by the 'stability issue'.
I wouldnt send him to an accident site for an apprasle.

[Mike Schallmann]

Birdy--Im an opinated hard liner --and I stand by my statement-- for these reasons --ANY TIME you do anything to a gyro that alters the stability quotient you adversly affect the safety margin. The distraction of having to deal with pitch instability may have interfered with the pilots ability to deal with other problems that were occurring. Additionally if he had been used to flying with the stab on his mindset may have not yet adapted to to the handling charecteristics of a recently stabless gyro--

FWIW --Im self taught and have well over 500 hrs in gyros --does that make me an expert -hell no --

My Unicycle comments were in respone to a previous assine post --

Careful Birdy using words like "stupid" may get you surgically excised from these posts! --Been there done that!

What does "Im blinded by the stability issue" mean ?? If it means Im concerned about gyro stability then you are correct --

Also --I have absolutely no desire to go to an accidenct scene --Ive seen enough bodies torn apart in my lifetime --

[chuter]

My Unicycle comments were in respone to a previous assine post --


Since I made the unicycle analogy I'm guessing you meant my post.

If you can't keep up with the logic involved here, don't resort to personal attacks.

Jumping to conclusions about accident causes contributes to the divide in the gyro community.

[Mike Schallmann]

Michael I see that your keeping in line with your signature: ""I've been ignorant and confused before, it could happen again.":puke:

Dont like what I post --put me on your dont read list-- but be aware I'll continue to talk about the IDIOTS who refuse to deal with stability issues--

BTW --Jim Mayfied says it best " Stability is NOT an option"

[chuter]

You haven't answered my question in one of my previous assinine posts:

If it was a control failure how did not having a HS contribute?

You may be right; not having a stab MAY have had something to do with it, but you don't KNOW that (unless you've been consulting with Johnathan's crystal ball).

Seems that you make fun of him and his fortune telling but you're doing the same thing.

[Mike Schallmann]

Chuter read the first paragraph in post #91--that should answer your question!

Also I NEVER said the fact that he didnt have a stab was the cause of the accident--what I DID say was that people who fly gyros without stabs are IDIOTS -- meaning that they totally disreguard all empiracle evidence that horz stabs are an important and intregal part of the stability of a gyrocopter!

It appears that your also looking in some type of Crystal Ball by stating it must have been some type of control failure

[chuter]

From your post #8:
“To think that a stab didnt contribute to this accident --is like an Ostrich sticking his head in the sand!”

You said:
“It appears that your also looking in some type of Crystal Ball by stating it must have been some type of control failure”

Where did I say it MUST be a control failure?

I’m saying WE DON’T KNOW!!

At this point discussing the possible causes is good and makes us think, jumping to conclusions gets us nowhere.

You still haven't answered the question other than to reference your post #91. Tell me; if the control rod breaks on a gyro with a stab at 100ft altitude, how is the stab going to help?

[chuter]

The question I posed in my last post got me thinking.

Suppose you have a gyro that meets all the ASTM stability requirements, and it was trimmed so it would fly hands off.
If a control rod broke could you still have reasonable control using throttle and rudder?
Possibly enough control to land if you could find a spot?

[Doug Riley]

Maybe, but you'd need a long, smooth place to set down or a howling wind to land into. If the machine really is trimmed to fly hands-off at, say, 45, then it'll fly at that speed no matter what the throttle setting. When you cut power to get down, it'll glide at 45, quite nose-down as usual. You'd probably want to carry some power and descend gradually. Then ADD some power to level out (don't hit nose-low!) and do a fast run-on landing. On rough terrain, you'll likely hit something or do a hard forward tumble -- unless you're lucky enough to land into a strong wind.

Some control systems produce a bias by virtue of their weight, and the balance is upset when they get disconnected. Pump sticks and overhead sticks both add a nose-down bias, for example.

An in-flight adjustable trim system that works independently of the control linkages offers redundancy. Maybe the ASTM standards ought to require that; we've lost at least three well-know pilots to control system failures, even if Kelly's accident wasn't one.

[C. Beaty]

My crystal ball says; NTSB final report: “Probable cause: Pilot failed to maintain control.”

I hope I'm wrong.

[Mike Schallmann]

RE post #8

I DIDNT say caused I said CONTRIBUTE -- if you dont understand that there is no help for you-- what amazes me that you and others still will not accecpt the fact that the lack of a stab MAY be a contributing factor --just going on statistics alone it PROBABLY could be considered the major factor--

According to the dictonary and this is how I use the word probably : reasonably so -but not proved.

There are lots of scenarios where a stab would have no effect on the outcome-- it is theoritically possible to survive a control failure --several years ago one of the guys in our club did --his control stick broke off --it was well trimmed --luckily he was over the runway --he pulled the power off SLOWLY and controlled drift with the rudder--just as he was about to touch down he applied full power and kinda sorta flared--he hit harder than normal but the gyro survived.

[chuter]

Mike,

Can you admit that it's possible that not having a stab did not contribute to the accident?

[Mike Schallmann]

Chuter per your post


"The witnesses further reported that while on the downwind leg of the traffic pattern, the gyrocopter appeared to fly straight and level at an estimated altitude of 100-150 feet above ground level (agl). Near the midfield point, the gyrocopter suddenly pitched to a nose down attitude and subsequently impacted the ground. One witness reported that the gyrocopter descended with an approximate nose down angle of 60 degrees "while rolling left and right."


At 100 ft -this is in all probability (see previoius post ) a bunt ---

A control failure should not cause an uncontrolled roll --you might go one way or the other --but certainly not back and forth --I know this because I fly gyros -- if you begin a roll in one direction it takes a it takes concerted effort to arrest that roll and go in the opposite direction --with control failure you would be unable to arrest the roll and reverse it --disconnect one of your control rods (on the ground) and see what kind of control authority you actually have --

all initial indicators are for a bunt --none are for control failure! But then I could be wrong and ya'll could be right ---

[Mike Schallmann]

Birdy

One more thing --Most investigators go into an accident with somewhat of a preconcieved notion of what happened. This is NOT necessairly a bad thing -- Most investigators will try and find the facts -and make every effort to prove or DISPROVE whatever notions they have.
I have conducted literally thousands of investigations in the criminal justice field --reguardless of preconcieved notions --I was only interested in the facts-- my recommendations were based on facts --sometimes they supported my initial feelings --sometimes they didnt--

I took a good look at the wreckage of the fatility accident at El Mirage several years ago-- my initial reaction as I SAW the accident occur --was that a blade came off ---after viewing the wreckage and all its carnage I realized that it was a BUNT-- had I not looked at the wreckage it would have been nearly impossible to convince me that it was indeed a bunt---

[gyropilot]

I can't be the first to have noticed the similar statements from witnesses in certain fatal gyroplane accidents where they report seeing the gyroplane rolling rapidly from "side-to-side" or "jumping" from left-to-right before (or during) a nose dive and subsequent impact. It makes me wonder if this observed movement is caused by either the rotor blades hitting parts of the airframe (likely the tail) and/or the hub bar hammering parts of the rotor head as the blades stall and loose rigidity.

Note of the observations of witnesses in the following two local accidents where friends of mine died. The first was most certainly a power-pushover as evidenced by the tail being struck in the classic manner by the rotor blades! The second accident *may* have been PIO followed by a power-pushover, but since no mention was made in the report of marks on the tail, the prop blades, or the airframe, it's inconclusive.

SEA01LA008

He continued, reporting that "...seconds later he observed the rear of the gyroplane swaying back and forth and parts falling off the rear portion of the aircraft...," and that "...the aircraft then went straight down and crashed into the woods..."

An inspector from the Federal Aviation Administrations Flight Standards District Office in Renton, Washington, conducted the on-site examination of the wreckage on October 24, 2000. He reported that the wreckage was confined to a relatively small area with the exception of a diagonal section from the upper portion of the rudder, and one of the propeller's composite blades. These two items were located approximately 150 to 200 feet from the ground impact site.

The top of the rudder panel was observed to have been separated along a diagonal line progressing from the upper-forward edge to the trailing edge of the control surface (refer to photographs 1 and 2). The line measured approximately 25 degrees below the edge of the top of the rudder panel. A second abrasive type mark was noted at the very top-aft portion of the rudder panel.

SEA99LA151

A number of aeronautically experienced witnesses saw the accident sequence and their statements provided the following consistent observations: The gyrocopter departed runway 15 climbing to an altitude of approximately 300 feet above ground level (AGL) and maneuvered towards the west. The engine was developing power and the rotor blades were observed turning. The gyrocopter was then observed to execute a series of "pitch oscillations" as described by several witnesses, "oscillating" by another witness, and was reported by another witness to have "violently oscillated." Two other witnesses reported the maneuver as a "jump to the left fairley [sic] violently then back to the right" and it "rocked to the left then to the right." Most of the witnesses reported hearing a "popping" sound. All reported that the gyrocopter then pitched over and descended steeply to the ground (refer to attached statements).

Note the similarity of witness observations in the above two accidents to Kelly's accident below...

DFW07FA071

One witness reported that the gyrocopter descended with an approximate nose down angle of 60 degrees "while rolling left and right."

[Fl90]

Chuter, take offs and landings without cyclic input were done by Bensen to show the ability of a trimmed gimbal head. However, the parts of a control system play a part in the balance of the system. Without some portion of the system, I think the balance would be off.

[bpearson]

An in-flight adjustable trim system that works independently of the control linkages offers redundancy. Maybe the ASTM standards ought to require that; we've lost at least three well-know pilots to control system failures, even if Kelly's accident wasn't one.

Two pilots (and one passenger) owe their lives to an inflight adjustable pitch trim in the UK when the stick suddenly came off in their hands. One was my old machine and was the only one such fitted to a Benson clone. Getting approval to fit this from the British authorities was a nightmare.

[Heron]

I planted a tree of IF in my garden, it almost grew!
Pilot fail to maintain control is great!
Guess you can apply that to all accidents . . .
Heron

[reelmule]

It should be noted, in a rotorcraft as in a FW, one can use rudder to raise the opposite wing (read rotor). This may have accounted for the ocillations right and left. Just a thought.
Walt

[Doug Riley]

Walt, yes, sort of. In a FW, the mere act of yawing with rudder will make the advancing wing rise. In a rotorcraft, you have to actually start slipping before the rotor blowback gives you a bit of dihedral-roll effect.

It's a pretty weak effect, though.

[Jonvee]

I would think that you may not loose rotor thrust and control all at once. As your machine reduces rotor thrust the stick starts feeling funny. The wiggle could be the pilot stirring the stick trying to regain that normal feel (stick pressure).

[barnstorm2]

I know that when the rotor begins to get close to flapping on the ground while taxiing the stick starts jurking randomly in your hand.

Is a rotor (rpm)stall warning indicator practical?

Or would it just beep only in time to tell you what your are about to die from?

I can't find it now but a few years ago I remember discussion of a potential device that would cut throttle (spark) at a set low RRPM.



.

[pwendell]

I think Doug put the blame for our horrible safety record right where it belongs -- on our collective p1ss-poor attitude when it comes to being SAFE pilots.

In my opinion, what we lack as a community is a proper aeronautical EDUCATION. All of the focus on training generally seems to be on the stick and rudder stuff, which although important, is really the fun and easy part of flight training. The much more difficult and, in my opinion, more important part of flight training, is developing the pilot's judgement.

Good judgment requires a solid fundamental understanding of gyroplane aerodynamics so that the pilot can understand WHY the gyro does what it does, and so that he/she can accurately predict its behavior and make a reasonable guess at what to do when he/she encounters an unfamiliar flight regime, and so that he/she can recognize dangerous situations early before they become unmanageable. (As Birdy would say, "Sh1t happens.").

Good judgment also depends on making honest and frequent self-assessments. Every flight is an opportunity to learn, and every flight presents things that can be improved upon. One of a pilot's primary duties is to continuously learn from his/her mistakes and to incorporate these lessons into their future flights. A sizable portion of Humility helps a lot with this.

Finally, good judgment depends on a thorough understanding of sound Aeronautical Decision Making and Best Practices, and the legal rules of the sky. This includes things like always using checklists, getting a weather briefing or at least checking the forecast for local flights, having pre-established and pre-briefed decision thresholds -- e.g., minimum acceptable fuel, maximum x-wind components, performance minimums that must be met before takeoff, defined emergency procedures, etc. It also includes having personal minimums that must be met, like enough sleep, calm emotional state, etc. Finally, it requires that we understand our own mental flaws -- the types of bad decisions we tend to make -- and take conscious, purposeful steps to keep our flaws from taking over.

There has been a fair amount of talk on this forum over the years about the mechanics of flying gyros and about the physics of a stable machine, but very little talk about the mental practices of a safe pilot. In the end, a gyro, no matter how stable, is only as safe as its pilot.

[birdy]

I]Careful Birdy using words like "stupid" may get you surgically excised from these posts! --Been there done that![/I]
Riteo, i wont call you stupid if you dont call me an idiot. ;)
BTW Mike, i woulda done more n 500 hours ina gyro wen i decided to take the HS off and see wot difference it made. This bloke apparently had 10,000[??] hours, id recon his head woulda bin switched on.

What does "Im blinded by the stability issue" mean ?? If it means Im concerned about gyro stability then you are correct --
No, it dont mean that.
Your post No. 8 sounded like you recon ol mate crashed coz he never had a stab on his machine, simple. Sounded like you are sayn he crashed it coz it was [ supposedly] unstable, coz it never had a stab, and this ment he didnt know how to fly it.
Me ferel hasnt had a stab on it for over 2000 hours[ i know, im an idiot], and it hasnt crashed yet,[ not stab related anyway ;) ] and i got no where near the hours this bloke had, and he had his off for wot? 10 mins?
I may be reading you rong, but thats how it was interprited by me.

Spoton post Peter W.

[birdy]

Just found this;
I guess that's what he learned on and he said the stab in the prop wash kept him from swinging the nose up like I've seen birdy and Chuck B. talking about.
:(
Gess i better take me bat n ball n go away ay.

[chuter]

Didn't mean anything bad about swinging the nose up birdy, I was just sayin' Kelly thought it was more manueverable that way without the stab, and I think that's what you've said before and Chuck B. even said was true (standing it on the prop, I think he called it).

[Tina]

Finally, good judgment depends on a thorough understanding of sound Aeronautical Decision Making and Best Practices, and the legal rules of the sky. This includes things like always using checklists, getting a weather briefing or at least checking the forecast for local flights, having pre-established and pre-briefed decision thresholds -- e.g., minimum acceptable fuel, maximum x-wind components, performance minimums that must be met before takeoff, defined emergency procedures, etc. It also includes having personal minimums that must be met, like enough sleep, calm emotional state, etc. Finally, it requires that we understand our own mental flaws -- the types of bad decisions we tend to make -- and take conscious, purposeful steps to keep our flaws from taking over.


In my opinion you hit the nail on the head about the gyro world. I see this also and if there is any restrictions put on us flying experimental or ultralight gyros it should be mandatory ground school.

[barnstorm2]

.....if there is any restrictions put on us flying experimental or ultralight gyros it should be mandatory ground school.

I would agree if that ground school included learning the physics of gyroplane stability.

[Douglas Riley]

Here's a little sketch I've used in the "ground school" part of my syllabus. "Ground school" consists of sitting on the back of the gyro trailer between flights, sketching and doing some serious hand-jive. We spend about equal amounts of time doing this and actually flying. (Fees are based on flight-hours, though.) I added 4-5 questions about pitch stability to the ASC test. Answers refer to the sketch, which is attached to the test.

None of this does the least good, of course, if the student won't listen. The non-listeners are those who either (a) don't "believe" in science or (b) are of the "real men don't need no stinkin' H-stabs" school.

Attitudes (a) and (b) (= anti-authority and machismo) are specifically cited in aviation decision-making courses as obstacles to safety. But if you're anti-authority you won't listen to a decision-making course, either. In fact, you insulate yourself from all new knowledge unless you've gathered it personally. Such mindsets are a huge problem here in Gyroville.

[C. Beaty]

Evolution is a slow process. While our ancestors were still tree dwellers, survival of the fittest required agility, coordination, fangs and claws.

Once our primitive ancestors came down from the trees and began walking upright, survival required an entirely different set of skills. The ability to think and reason became more important than the ability to leap from branch to branch. The ones who survived learned that it is better to husk a coconut with a pointed stick and crack the shell by dashing it against a rock than to attack it with tooth and claw.

Those people who believe stability isn’t important are attacking the coconut with tooth and claw.

[scottessex]

Has it been determined a "control failure"? The brock stick has really cheesy mounting system of a couple of sharpened bolts with a jam nut, that run in a couple of shallow divots at each end of the control stick, if one of these jam nuts came loose the whole control stick assy comes off. Just speculation, but I would think this would be a weak link before a control rod came loose.
The KB3 I had always worried me, I had installed safety wire through the slots in the stud and wired the nut, but I still didn't like it.

I hope that The NTSB can reach an accurate and timely report.

[dick]

How about rotorblade stalling at a low rotor rpm just after take off. caused by not allowing the blades too accelerate enough speed to climb out as well as to counter enough air authorty to overcome wind shift and other weather related affects. My though is this, when you lift off the runway you have just enough rotor speed to fly maby a little more. under the right conditions say abrupt airflow change at low rotor speed then blade flap is neer. I know Chuck Beaty & Doug Riley may want to jump on this one.............Dick

[Douglas Riley]

Dick, the rotor may be a little shy of full flight RPM right when you un-stick. At that moment, it's possible even to get some tapping on the teeter stops (though it's rare on small gyros). Still, this is nothing like a total blade stall and, in any event, the condition goes away before you can do any climbing.

The blade tips are travelling at some 300 mph at the tips. This high speed has the effect of greatly "diluting" changes in blade airspeed and blade angle of attack caused by wind shears and turbulence.

Something less mysterious was almost certainly to blame here.

[dick]

Dick, the rotor may be a little shy of full flight RPM right when you un-stick. At that moment, it's possible even to get some tapping on the teeter stops (though it's rare on small gyros). Still, this is nothing like a total blade stall and, in any event, the condition goes away before you can do any climbing.

The blade tips are travelling at some 300 mph at the tips. This high speed has the effect of greatly "diluting" changes in blade airspeed and blade angle of attack caused by wind shears and turbulence.

Something less mysterious was almost certainly to blame here.

Could be Doug, maby not so mysterious though, something brought down an (i beleave) last year an RAF under similar circumstances just after takeoff. High time pilot, good flying gyro & wind involved. I've gotten into the pratice of just after lift off say around 20 ft. or so level off and gain more air speed which means greater rotor speed for better climb out...............Dick

[Jazzenjohn]

Am I understanding this correctly? The gyro was built and flown for several hundred hours without serious problems by John Stevens, he sold it about 18 months ago to someone who flew it for an unknown number of hours without any serious problems. He then removes the stab because it interferes with his ability to make quick pitch changes and renders the gyro less manouverable and he immediately crashes? Am I missing something?

[Harry_S.]

John,


It is my opinion that the HS had no bearing on this incident, attached or not attached, per the limited information available to us now.

I will try to maintain an open mind till the investigative results are in...but I have to speak my mind when I read something that is counter to my experience in flying non stabbed gyros.

Kelly was also well experienced in flying non-stabbed gyros.


Cheers :)

[Jazzenjohn]

How recent was this experience flying non stabbed gyros?

[Harry_S.]

Could be Doug, maby not so mysterious though, something brought down an (i beleave) last year an RAF under similar circumstances just after takeoff. High time pilot, good flying gyro & wind involved. I've gotten into the pratice of just after lift off say around 20 ft. or so level off and gain more air speed which means greater rotor speed for better climb out...............Dick



Can you be more specific Dick, of the accident last year?!

I endorse your practice of leveling off after liftoff, then gaining airspeed before initiating the climb. Good procedure. ;)


Cheers :)

[Harry_S.]

How recent was this experience flying non stabbed gyros?



Whose experience do you have reference to?!


Cheers :)

[Jazzenjohn]

I was asking the question of how recent the experience of flying non stabbed gyros was for Kelly? I was under the impression that when John sold him the gyro, he hadn't flown gyros for quite some time (years?) so it may have been many years since he had flown a non stabbed gyro. On the other hand he could have had recent lessons or some sort of refresher in flying them very recently. I don't know.

[Harry_S.]

I was asking the question of how recent the experience of flying non stabbed gyros was for Kelly? I was under the impression that when John sold him the gyro, he hadn't flown gyros for quite some time (years?) so it may have been many years since he had flown a non stabbed gyro. On the other hand he could have had recent lessons or some sort of refresher in flying them very recently. I don't know.


I don't know the complete story/history either John.

I'm speaking here as regards my personal experience, and I liken it to be similar to ones experience in riding a bicycle, if you will. I hadn't rode a bicycle for something for like 40-45 years untill after I retired and decided to get a bike, for exercise.

I was a little shakey at first with the 180* turns but after an hour or so, I was cool with it.

Once you're experienced in non-stabbed, unstable gyros and are away from them for a while, like I was, it's no problem at all to get back in the fold.


Cheers :)

[Mike Schallmann]

Jazzenjohn

If GOD:director: came down and told us that a horizontal stab would have saved this person--there are those who would continue to doubt it --:lalala:

[Jazzenjohn]

I'm just asking questions... The issue is too divisive to do much else without the discussion degenerating. You couldn't change anyones mind intellectually because everyone is forced onto a side and no one is able to change their mind one way or the other without getting slammed and losing "Face". I don't have all that much time flying in them myself.

As far as the bicycle analogy, I don't know how long it would take to regain facility with the difference between stab or not as I have zero actual experience flying a stabless machine, I know If I don't fly for a couple months during winter I feel pretty out of it for a few minutes to an hour or so, then I feel fine. I also don't know if he flew without the stab for a few minutes or many months.

[Chuck_Ellsworth]

Jazzenjohn:

There is nothing wrong with your questions, do not get discouraged by people defending the no HS mindset.

I have been in the pilot training business for close to 50 years and it is my opinion that flying any aircraft that is so unstable it can kill you in a heart beat because you think training can prevent such an occurance is flat out wrong.

[mceagle]

I've gotten into the pratice of just after lift off say around 20 ft. or so level off and gain more air speed which means greater rotor speed for better climb out...............Dick
G'day Dick, airspeed has very little bearing on rotor speed (only indirectly in some cases).
However your practice of leveling off to gain manouevering airspeed is a good one.

[dick]

Can you be more specific Dick, of the accident last year?!

I endorse your practice of leveling off after liftoff, then gaining airspeed before initiating the climb. Good procedure. ;)


Cheers :)

Hello Harry, sorry i'm trying to remember who it was. I read about it on the Forum last year. The pilot had just lifted off and was in a climb when somehow he (they say) unloaded his blades. Dosn't sound practical to me but it had all the ear marks. I'll keep looking, if I find it i'll post it..........Dick

[dick]

G'day Dick, airspeed has very little bearing on rotor speed (only indirectly in some cases).
However your practice of leveling off to gain manouevering airspeed is a good one.

Thanx Tim, and top of the morning to ya. :D

[birdy]

it is my opinion that flying any aircraft that is so unstable it can kill you in a heart beat because you think training can prevent such an occurance is flat out wrong.
Chuck, you know thats not the argument. :(
In my oppinion, i dout theres a poster here that would argue against that logic.

[barnstorm2]

John,
It is my opinion that the HS had no bearing on this incident, attached or not attached, per the limited information available to us now.
I will try to maintain an open mind till the investigative results are in...but I have to speak my mind when I read something that is counter to my experience in flying non stabbed gyros.
Kelly was also well experienced in flying non-stabbed gyros.
Cheers :)

Harry,

I would have to agree. While I see nothing wrong with discussing the POSIBILITY of a bunt we don't really have any idea at this point and the pilot did have experience with a stabless machine.

I am no fan of unstable gyroplanes but I agree we need much more info to even place a good bet.

However, one thing keeps nagging me. That is did he just work on this machine and then go flying in gusty or high winds?

If this was the 'test' flight then 2 issues come up. Issue 1 is control failure due to improper mantainace and Issue 2 testing a newly modified machine in marginal weather.

[dragonflyerthom]

Good points Tim

Both are valid concerns.

[Doug Riley]

Dick, PPO accidents very often happen on climbout. The PPO moment caused by a high thrustline is at its maximum during wide-open throttle operation. What's more, when the aircraft is low, the pilot is more reluctant than usual to cut power if he hits a downdraft or begins oscillating. RRPM "lag" on takeoff isn't a factor.

Staying level after un-sticking is a good policy, in that you'll otherwise be trying to climb behind the power curve. A high-powered machine can easily climb at below its best rate-of-climb speed, but that doesn't make it a good idea. If the engine quits, things will get ugly. Again, it's not an RRPM issue, just the usual airspeed management stuff that all pilots face.

[Harry_S.]

Tim, I agree with your Post #138.

We'll have to wait for the investigative results.


Cheers :)

[dick]

Dick, PPO accidents very often happen on climbout. The PPO moment caused by a high thrustline is at its maximum during wide-open throttle operation. What's more, when the aircraft is low, the pilot is more reluctant than usual to cut power if he hits a downdraft or begins oscillating. RRPM "lag" on takeoff isn't a factor.

Staying level after un-sticking is a good policy, in that you'll otherwise be trying to climb behind the power curve. A high-powered machine can easily climb at below its best rate-of-climb speed, but that doesn't make it a good idea. If the engine quits, things will get ugly. Again, it's not an RRPM issue just the usual airspeed management stuff that all pilots face.

Yea Doug, you could be right about this and still we could all be looking in the wrong place. For me and " i'm sure everyone else" there are just too meny good and high time pilots that this type of thing is happaning to. It's got to be something were overlooking or not consitering. It creeps up to fast and pilots that know what to look out for are not reacting to it properly...........I guess we'll all haft to wait & see what investigative teem comes with again.....Dick

[Dean_Dolph]

.....there are just too meny good and high time pilots.....DickHigh time pilots are usually easy to identify. But how do you identify a 'good' pilot?

I posed a question to our instructors (it may have been on this forum) about how they measure pilot competency and never received a reply other than one or two saying that it was a subjective thing. And I suspect that there isn't a way to measure this. At least the way we presently test pilots and I don't have a suggestion as too how we do it differently.

If you lay out ten pilot's certificates, how do you tell who are the highly competent and skilled pilots? The certificates mean that the pilot met minimum standards during the check ride and that is all. We may be assuming too much about our pilots competency by the fact that they have a lot of hours.

I'm not suggesting that this incident was pilot error. I am suggesting that just because a pilot has a lot of time doesn't necessarily mean that the skill and competency is there. Unfortunately we have nothing but high time to tell us that a pilot is competent so when we take a ride we have to trust that he has the skill to get us up and down safely.

[Chuck_Ellsworth]

Would tens of thousands of hours flying with no accidents, incidents or violations of air law mean anything?

[birdy]

No.

But usualy it dose mean youd have a good 'feel' for the machine.
But all he's done in those thousands of hours is put round in good air, he's still likely to get ' suprised' if he gets out of his comfort zone.
Im no expert, but id done a few hours before i cracked the thousand foot barrier, and you can be sure i wasnt comfortable.
I still couldnt do at alt wot i do at ground level, coz im still not comfortable up there.

[gyrogreg]

Yea Doug, you could be right about this and still we could all be looking in the wrong place. For me and " i'm sure everyone else" there are just too meny good and high time pilots that this type of thing is happaning to. It's got to be something were overlooking or not consitering. It creeps up to fast and pilots that know what to look out for are not reacting to it properly...........I guess we'll all haft to wait & see what investigative teem comes with again.....Dick

Dick, Here's my opinion for what it's worth. This is not an opinion on this particular accident - need the investigation to proceed. But, this is my opinion on why even good pilots are having accidents:

Dynamic Stability: For gyro, particularly because we control pitch with the powerful and highly responive and leveraged cyclic control,of the "main wing" - the rotor - Dynamic Stability between gyros can make such a huge difference in the skill levels required to fly each one of them! The differences between big HS, little, HS, and no HS is huge. A lot of "high time pilots" have honed their proficiency skills on dynamic stability charactistics that are just enough different on the gyro that they died in!

A reason this is so important is that gyros can have very high natural oscillation frequency and pitch rates - especially light, single place gyros. A poorly dynamically damped gyro can be made to "ring" or oscillate in pitch at this high rate if it gets just the right excitation input. Like a glass that shatters with just the right musical note, a gyro can be excited into it's natural oscillation rate if the pilot or wind "strikes just the right note!". So, it takes just the right excitation - which contributres to why it doesn't happen all the time. Turbulence and pilot reaction can be just the right excitation for a particular gyro, and not another one that has a different natural oscillation rate or better dynamic dampening.

If a gyro is excited into this natural oscillation, if that oscillation proceeds through enough cycles, the pilot can react or over-react - sending those oscillations into true PIO! Those natural oscillation rates on some gyros are far too quick for a pilot, any pilot, to react properly to and stop - so to try can readily become PIO!

How do we prevent this natural oscillation, if excited, from progressing into PILOT INDUCED oscillations? We do that with a pitch dampener - a HS. With no HS, or with an ineffective HS, there is no pitch dampener (unless you use a computer auto-pilot dampener and control like the fighter jets use!) Lacking a pitch dampener is highly likely to allow strong enough and extended enough oscillations or pitch rates to excite a pilot into over-control or PIO. A moderate pitch dampener might dampen the natural oscillation or pitch rate enough that the pilot does not react and make it worse! The best pitch dampeners stop any natural oscillation within 1/2 cycle - so the aircraft responds quickly to a commanded pilot input, but any oscillation is "damped" to zero so quickly that the pilot is not excited into over-control - not excited into a "jab and counter jab" that is required on unstablilized gyros and can initiate over-contol or PIO!

It is not just PIO that is the issue here: Even just an over-control - excited in the pilot by a sudden "undamped" pitch excursion - could progress into a buntover or Precession Stall even before any oscillation starts.

So, even for "high time" pilots, switching to a less dynamically damped gyro, could surprise that pilot with proficiency requirements they did not have or even expect to need. An example: Jim Smith, CH 35, flew his Bensen for 15+ years without a HS. He installed a good HS - Dominator "T" tail and flew it for another 5-10 or so years - now with dynamic pitch dampening that it did not have before. Then, he damaged the tail and installed just a tall tail - no HS. He reasoned he had flown without a HS for many years - no sweat. His first flight was very short - he could not get back on the ground fast enough! He taxiid up and said he could not fly that machine, he thought he was going to die! He took time, over months, balancing on the mains, and short flights in mild winds, etc. to regain his earlier proficiency to fly that gyro again without a HS. I do not believe that just because you flew a gyro of one dynamic stability, that you can immediately fly a lesser ptich damped one. Would an acrobatic pilot who had been away from acrobatic airplanes suddenly just get back into a Pitts Special and go flying?!? Not the smart ones - but they have the advantage of expecting that the Pitts would be a challange again after years of nothing but Cessnas and Pipers - they know and expect the difference! Too many gyro pilots, IMHO, do not know or accept or respect the difrerences between stable and unstable gyros. Without a HS, there is no dynamic dampening!

In Texas a few years ago, a 4-5 year Dominator pilot built a KB - and went for the first flight in windy conditions. He made it to downwind! It would have helped if he had at least expected it to handle differently - now that it did not have a dynamic dampener of any kind! If he had understood that his proficiency would be so challenged, at least maybe he would not have flown in such wind!

Please fly safe - Greg

[dragonflyerthom]

Great examples Greg G

You have probably explained this the best it can be done. Each gyro is different even in the same type. So you can't just jump in one and expect it to be like all the others you have flown.

[birdy]

So you can't just jump in one and expect it to be like all the others you have flown.
Thom, i havnt fown that many, probably bout 15 or so, but they all feel different.
The only constant is the rotor, they are all the same.
Iv found that once im off the ground, a gyro isa gyro, and the only difference is the RATE at which it responds.

[dick]

Thank you Greg, that explains better then anything i've ever heard thus far. We need to copy that so's we can send it to newbees and doubters who are looking for answers to a question not easy to see. My problem is that I havn't been around other Gyro pilots long enough to try and understand why they have a hard time transating. For myself I fly both stable and (by most every one else's definition) an unstable gyro back to back all the time and don't feel the difference. Maby because i'm so actlamated to both so much, that I can not see it. Again thank you very much for taking the time to explain......................Dick

[Harry_S.]

Good post Greg...and it was one of your shorter ones as well. :D :D


Cheers :)

[barnstorm2]

Well, if no one minds me extrapolating on second and third-hand information...

Pilot removes HStab from known good gyroplane.

Reported or assumed reason for removing HStab is for assumed greater 'maneuverability' in pitch axis. (Possibly bad decision making on the part of the pilot (no HS=more maneuverability is arguably incorrect) )

Sometime after removing the HStab (possibly on text flight) pilot flys gyroplane in windy conditions (possibly bad decision making on the part of the pilot (don't test fly or fly newly modified aircraft in marginal conditions) )

Pilot dies in gyroplane after it impacts the terrain for unknown cause.

Current popular hypothesis for cause 1. Bunt 2. Control failure.

Cause 1. Bunt due to power push over. Leading factor: Poor decision making 1. Removing HStab, 2. Learning to fly newly modified pitch unstable gyroplane in marginal conditions.

Cause 2. Control failure. Cause unknown mechanical problem. Possibly related to removal of HStab, possibly related to testing in marginal conditions after making alteration to aircraft.



.BTW great post Greg. After reading that I don't understand how or why anyone would fly an unstable gyro....

.

[Paul_Zurawski]

Just so everyone is looking in the right direction...has any medical problems been ruled out yet?

[magilla]

Folks - a lot of good posts, a few excellent ones, and others that fall into the "impassioned" category.

From an outsider's perspective who HAS NOT flown a gyro, but has had over 2000 hrs flying helos:

1) Ground School should be mandatory. I was trained by the Army, so mine lasted a full year. 1/2 the day was school, the other half flight training...sometimes what we learned in the morning we practiced in the afternoon, but that was just pure luck....

The point is that the basic understanding of aerodynamics, CG, RRPM, and lift vectors is crucial to understanding what you're doing BEFORE you go flying a gyro or other RW aircraft... Driven, Driving and Stall regions, What happens in left and right turns and abrupt maneuvering, rotor blade stall, 2 per rev vibration, compressibility (yep, you can do it in gyros), and basic aerodynamics should be a minimum. Can you fly without this stuff? Sure, but you can train a monkey to wiggle sticks...Doesn't make him a safe pilot.

Nobody, not even Doug or C. Beaty try to do aeronautical calculations while they are flying... But they will prove or disprove the way a rotor behaves with math. And they will know what maneuvers and what AoA's will get them in trouble. Not all pilots need this extensive ability, but the basics of aerodynamic stability are important.

2) Ground training needs to be reinforced with regimented flight training. I am sorry, but a mere 20 hours is not sufficient in my book to sign someone off as proficient. Maybe if they have another rating, but not from scratch. Many will argue this point, especially those self-taught. I am speaking in terms of *should* for our community, not "it cannot be done without it."

3) We need to come up with some type of flight simulator for a gyro. Birdy is ABSOLUTELY RIGHT - RRPM is RRPM and gyros, regardless of HStab or not, will exhibit the same control characteristics based upon RRPM. That being said, we need simulators that show how we get into dangerous spots, when they happen, and how to get out of them. More importantly, how NOT TO get in them.

4) Even with the proper training, some machines are more dynamically and statically stable than others, and make for *safer* aircraft. Why we have arguments about this is beyond me. Just sitting there, some machines are more stable than others.

Stability, however, only equates to Safety in the hands of a competent pilot. Untrained yahoos can crash the most inherently pitch stable gyro if they don't manage RRPM correctly (or pull "bozo no-nos"). On the other hand, a well trained, experienced pilot can fly an inherently unstable machine safely all day long. But, depending on the conditions, he/she may not be able to overcome the inherent instability of a certain type of aircraft.

This principle is true - Doesn't matter if you are in the gyro world, helo world, or the FW world. The guy who restored that beautiful shiny silver 1930's racer plane developed and test flown by Howard Hughes crashed it within a year of being restored. It had inherently inefficient rudder and elevator control surfaces to minimize drag....



5) I fly UH-60 Blackhawks. The 40 sq feet of horizontal stabilator 45 foot aft of the mast slews from 6 degrees up to 34 degrees down to keep the helo level at different airspeeds. It's 4-6 degrees down at 140 KIAS (do some math on those resultant vectors!!!) Back in the '80's, when they had shielding problems on the wiring, the stabs would slew full down in flight - thus causing a downward pitch moment that even 22,000 lbs of Lift could not overcome...

So do not EVER tell me that a HStab has no effect on stability. I will grant you that a stabilator is different than an HStab, but even fixed in place it adds so much stability to the UH-60 as to make it rock solid in flight.

6) Not enough info yet to make the jump from "No HStab" to "cause of crash." Those of you firmly entrenched on either side of the debate have already made up your minds, so it doesn't really matter when the results come out. Each camp will see what it wants.

What we need as a community is to recognize the loss of a life. Regardless of HStab. Then we need to come together and agree that there are a couple things we need to do as a community:

1) Increase Training requirements

2) Increase Stability standards for gyroplanes.

Tina - yes we are still in the experimental category - but that doesn't mean we need ignore the 70-80 yrs of pioneers that came before us in gyros, and learn from their experience. In other words, we don't need to re-pioneer the gyro plane and relearn the mistakes. That's just not smart. Regrettably, that means there is less of the "frontier" attractiveness of gyroplanes. It is something that I am willing to sacrifice for a modicum of safety.

The question is, and it is the question that equates to the survival of this sport: Are YOU willing to enforce some standards on gyroplane stability before Big Brother does it for you? We all need to ask ourselves that simple question.

If the answer is yes, and I think a large preponderance of the community is in the "yes" camp, then we need to put away our petty squabbles and agree to enforce some minimum stability standards.

We also need to recognize that the manufacturers of unstable machines HAVE TO deny any instability issues for survival in this litigation-happy world. Were RAF ever to admit instability issues, don't you think EVERY RAF accident widow/widower would come out of the woodwork to sue? Same for all other types of manufactured kits.

So establishing a minimum stability standard, like X square feet of Hstab, and Y sq feet of rudder would go a long way to increasing the stability of all gyros. This way, the manufacturer can make changes without being liable. Win-Win, in other words.

So what do you all say? By type, can we not come up with an agreeable standard or range for disc-loading, Hstab size, Hstab location, distance from CTL, and rudder size that we can enforce ourselves?

How about enforcing these standards for NEW gyro pilots? Pilots with less than 500 hours?

Heck I don't profess to corner the market on good ideas, folks, but we gotta do something before Big Brother FAA does it for us.

Sorry for the length of this post.

[Doug Riley]

Paul Zurawski: The NTSB has yet to report on Terry Eiland's crash almost a year ago. They do not move quickly, and they don't release any analysis ahead of their probable-cause (=final) report. This one will take awhile, too.

If the PRA's incident response team has participated in the investigation, I haven't heard about it.

Magilla, RRPM is much less an issue in gyros that in helicopters. By design, a helo rotor is a one-speed device, thrust being controlled by collective and throttle. A gyroplane rotor is a variable-speed device; the rotor arrives at, and holds, commanded RRPM by means of a feedback loop.

Loss of RRPM is rarely the cause of gyro accidents although, of course, the rotor will slow down if it first stalls and hits the prop. The stall, however, is typically caused by a violent flip resulting from airframe instability, not by some joker who fails to watch his rotor tach (which most gyros don't have).

[msmfi]

Magilla,

>> Were RAF ever to admit instability issues, don't you think EVERY
>> RAF accident widow/widower would come out of the woodwork to sue?

If I remember correctly: RAF was sued ... and won the case... (?)
Any one remembering the details ?

[Doug Riley]

Yes. The court held that the homebuilder, not the kit-maker, is the manufacturer. Therefore, the only person the victim can sue is himself.

It was only a trial-court case; there was no appeal. That means that other courts aren't bound to follow the same rule.

We've pointed out many times how kitmakers can improve their designs without admitting fault. Do a cosmetic makeover at the same time and claim the new one is sleeker and hotter than the old. Heck, if you raise the cabin so it aligns better with the engine, rake the seats back a bit, lower the cabin roof and extend your fairing back over the engine, it will even be true.

[reelmule]

Folks - a lot of good posts, a few excellent ones, and others that fall into the "impassioned" category.

From an outsider's perspective who HAS NOT flown a gyro, but has had over 2000 hrs flying helos:

1) Ground School should be mandatory. I was trained by the Army, so mine lasted a full year. 1/2 the day was school, the other half flight training...sometimes what we learned in the morning we practiced in the afternoon, but that was just pure luck....

The point is that the basic understanding of aerodynamics, CG, RRPM, and lift vectors is crucial to understanding what you're doing BEFORE you go flying a gyro or other RW aircraft... Driven, Driving and Stall regions, What happens in left and right turns and abrupt maneuvering, rotor blade stall, 2 per rev vibration, compressibility (yep, you can do it in gyros), and basic aerodynamics should be a minimum. Can you fly without this stuff? Sure, but you can train a monkey to wiggle sticks...Doesn't make him a safe pilot.

Nobody, not even Doug or C. Beaty try to do aeronautical calculations while they are flying... But they will prove or disprove the way a rotor behaves with math. And they will know what maneuvers and what AoA's will get them in trouble. Not all pilots need this extensive ability, but the basics of aerodynamic stability are important.

2) Ground training needs to be reinforced with regimented flight training. I am sorry, but a mere 20 hours is not sufficient in my book to sign someone off as proficient. Maybe if they have another rating, but not from scratch. Many will argue this point, especially those self-taught. I am speaking in terms of *should* for our community, not "it cannot be done without it."

3) We need to come up with some type of flight simulator for a gyro. Birdy is ABSOLUTELY RIGHT - RRPM is RRPM and gyros, regardless of HStab or not, will exhibit the same control characteristics based upon RRPM. That being said, we need simulators that show how we get into dangerous spots, when they happen, and how to get out of them. More importantly, how NOT TO get in them.

4) Even with the proper training, some machines are more dynamically and statically stable than others, and make for *safer* aircraft. Why we have arguments about this is beyond me. Just sitting there, some machines are more stable than others.

Stability, however, only equates to Safety in the hands of a competent pilot. Untrained yahoos can crash the most inherently pitch stable gyro if they don't manage RRPM correctly (or pull "bozo no-nos"). On the other hand, a well trained, experienced pilot can fly an inherently unstable machine safely all day long. But, depending on the conditions, he/she may not be able to overcome the inherent instability of a certain type of aircraft.

This principle is true - Doesn't matter if you are in the gyro world, helo world, or the FW world. The guy who restored that beautiful shiny silver 1930's racer plane developed and test flown by Howard Hughes crashed it within a year of being restored. It had inherently inefficient rudder and elevator control surfaces to minimize drag....



5) I fly UH-60 Blackhawks. The 40 sq feet of horizontal stabilator 45 foot aft of the mast slews from 6 degrees up to 34 degrees down to keep the helo level at different airspeeds. It's 4-6 degrees down at 140 KIAS (do some math on those resultant vectors!!!) Back in the '80's, when they had shielding problems on the wiring, the stabs would slew full down in flight - thus causing a downward pitch moment that even 22,000 lbs of Lift could not overcome...

So do not EVER tell me that a HStab has no effect on stability. I will grant you that a stabilator is different than an HStab, but even fixed in place it adds so much stability to the UH-60 as to make it rock solid in flight.

6) Not enough info yet to make the jump from "No HStab" to "cause of crash." Those of you firmly entrenched on either side of the debate have already made up your minds, so it doesn't really matter when the results come out. Each camp will see what it wants.

What we need as a community is to recognize the loss of a life. Regardless of HStab. Then we need to come together and agree that there are a couple things we need to do as a community:

1) Increase Training requirements

2) Increase Stability standards for gyroplanes.

Tina - yes we are still in the experimental category - but that doesn't mean we need ignore the 70-80 yrs of pioneers that came before us in gyros, and learn from their experience. In other words, we don't need to re-pioneer the gyro plane and relearn the mistakes. That's just not smart. Regrettably, that means there is less of the "frontier" attractiveness of gyroplanes. It is something that I am willing to sacrifice for a modicum of safety.

The question is, and it is the question that equates to the survival of this sport: Are YOU willing to enforce some standards on gyroplane stability before Big Brother does it for you? We all need to ask ourselves that simple question.

If the answer is yes, and I think a large preponderance of the community is in the "yes" camp, then we need to put away our petty squabbles and agree to enforce some minimum stability standards.

We also need to recognize that the manufacturers of unstable machines HAVE TO deny any instability issues for survival in this litigation-happy world. Were RAF ever to admit instability issues, don't you think EVERY RAF accident widow/widower would come out of the woodwork to sue? Same for all other types of manufactured kits.

So establishing a minimum stability standard, like X square feet of Hstab, and Y sq feet of rudder would go a long way to increasing the stability of all gyros. This way, the manufacturer can make changes without being liable. Win-Win, in other words.

So what do you all say? By type, can we not come up with an agreeable standard or range for disc-loading, Hstab size, Hstab location, distance from CTL, and rudder size that we can enforce ourselves?

How about enforcing these standards for NEW gyro pilots? Pilots with less than 500 hours?

Heck I don't profess to corner the market on good ideas, folks, but we gotta do something before Big Brother FAA does it for us.

Sorry for the length of this post.

A great post. You have absolutely covered 99.9% of the problems and issues of the gyro community. We need to all aspire to the solutions you have outlined--whether we are HTL (as I am), or CLT or LTL. AC safety, wether FW or RC is NEVER one dementional, in spite of the many posts to the contrary by the "Johnny One-noters" on this forum.
Keep posting!
Walt G.

[C. Beaty]

No reasonable person can find fault with what you’ve posted, Spencer.

However, it this particular instance, the victim was, by all accounts, a competent pilot, a gyroplane CFI and if I interpret the material I’ve seen on his and other web sites correctly, in the process of setting up an FAA approved ground school in partnership with the local area RAF dealer.

He had also been instructing in stabless RAFs so was probably under pressure to remove the stab from his personal gyro. It’s asinine to be teaching his RAF students a stab is unnecessary and dangerous as he must to be an approved RAF instructor and yet to have one on his own gyro.

The part that puzzles me is why someone, no matter how confident, would remove a stab and then choose to test it on a turbulent day at lethal altitudes. I’ve tested some unusual devices on gyros but always skim the runway at a safe altitude before venturing to pattern altitude.

I still expect the NTSB final report to state; “Pilot failed to maintain control and impacted the ground.” I hope I’m wrong.

[Doug Riley]

What the NTSB says will depend greatly on the assistance they get (or don't get) from our community. We have contributed to good, detailed, accurate analyses of accidents in the past. The investigation of Leroy Hardee's control-system failure was an outstanding example.

If we can get involved in this one, I think we can get past the kind of non-explanation that Chuck fears.

But who's helping NTSB? Anyone?

[Tom Evans]

My only input is to state this: Not only do we have contributors that know their beans, many of them are truly outstanding writers to boot!

[chuter]

Doug,

According to Jim Mayfield, Marty Weaver is on the PRA Incident Investigation Team, and he was present during the FAA/NTSB site investigation the day after the accident.

Marty is also the RAF dealer. I have yet to hear anything from him and don't really expect him to give out any more info. I'm guessing he'll want to let the investigation run its course.

Regardless of what the cause turns out to be, IMHO Kelly made what I would say are errors in judgement regarding safe flying practices: flying low in turbulent high wind conditions, and possibly test flying a new, less stable configuration in these conditions.

It may turn out that these didn't contribute to the accident, but it makes me want to not take chances.

These are things I hear about and see in gyro videos all the time; flying low downwind, close to objects on the ground, flying in high winds, etc.

This stuff looks cool and is fun, but if it's your day to die then it's because you were doing something stupid.

[Chuck_Ellsworth]

" If you were a CFI, would you teach a student to fly with a H-Stab, then turn them loose to solo, when the kit he owns does not have one? "

Would you?

[magilla]

Doug Riley, C. Beaty:

I agree with you about the loss of RRPM not being the cause of most gyro accidents, but in a lot of instances, RRPM (or lack therof) has everything to do with rotor stalls - and excessive flapping, which leads to, or is the precursor of PIO and PPO events?? Is that not correct???

Please correct me if I am mistaken.

As to the rest of my post, it just seems clear to me that WE need to do something to police ourselves.

I could care less the manufacturer, and I do not have any beefs with anyone particular maker - but in the end, information is king. People wanting to get into gyros, like me, will do research and determine what is an acceptable amount of risk, and they will see the controversy surrounding Hstab-less gyros.

If they are smart, they will make the right decisions. I chose the tractor gyro route, after about 14 months of research (heck, I was in Iraq - I had to have something to keep my mind occupied). Anyway, my decision was right for me - but like religion, I am not going to force my opinion on others. But I will not cast a blind eye to the stability debate. Gyros with H-Stabs are more stable than those without. Pure and simple. Tons of math to prove it, and only conjecture and wishful thinking to disprove it.

Most of what we are arguing is straight aerodynamics - it's not voodoo. And self-assessment and self awareness is going to be crucial to all of us making the right decision here. If the shoe fits (you have an inherently unstable gyro) then wear it. Own it. Own up to it.

Again, IMHO unstable does not necessarily mean unsafe - Birdy is a great example. Those videos on youtube are exciting to watch, and birdy is operating safely within his personal flight envelope. But the point is that newbies need not try that type of flying in an H-stabed machine, much less a stabless gyro.

Now Birdy, don't let this go to your head! You're one hell of a stick-wiggler, and from what I have seen, you FEEL your RRPM and manage your aircraft expertly. Unfortunately, not all of the pilots out there share that ability.

Hell, I don't care what type of gyro you fly - but sheesh, can we not ALL agree on the importance of an H-stab to aerodynamic stability? For tractors as well as pushers?

We still don't know enough to judge whether the poor man made a mistake, or was the victim of circumstance. I say we permanently suspend judgment here, in the name of coming to a common ground of agreement that H-Stabs are important to stability.

What say we stop calling each other stupid or idiots and come up with a set of standards?

"pusher gyro GWT 500-1000 must have an H-stab of at least 4 sq ft stationed 4-6 feet aft of mast."

Some of you experts out there give me a reasonable figure for minimum size...and we'll move on from there.

Man, we gotta start somewhere, even if it's a drag chute 25 feet behind the gyro...

Common sense needs to rule here, regardless of your personal feelings.

I don't want to fly in a world where everything is managed for you...but we need to speak up and police ourselves, or else the safety nazis will decree that the gyroplane COMMUNITY, not necessarily their aircraft, are the unsafe lot.

[Douglas Riley]

Spencer, the cause of rotor stall (specifically, cyclic or precessional stall, the kind involved in PPO and similar events involving violent frame rotation) is not primarily RRPM loss. It's a matter of cyclic pitch change being fed into the rotor faster than the rotor disk can tip, or precess. The maximum rate at which a rotor can accomodate such change is a function of the slope of the rotor blades' airfoil characteristics as compared to the blades' mass.

In gyros with a severe PPO tendency, precession stall appears to happen with little warning, at full 1G RRPM.

It's not clear than a pilot can cause such a stall with only a stick input. The teeter stops fight back hard. This is enough warning for even a very dull person. OTOH, when the frame whips around, energized by off-center engine-generated forces, the stops aren't enough to restrain the excessively fast + large cyclic input.

[magilla]

I found this at Despair.com

[magilla]

These need to be put on the walls of gyropilots...

[birdy]

Now Birdy, don't let this go to your head!
It didnt Spencer, coz i recon your exadurating.[ spelln??]
Hell, I don't care what type of gyro you fly - but sheesh, can we not ALL agree on the importance of an H-stab to aerodynamic stability? For tractors as well as pushers?
No argument from me there.

What say we stop calling each other stupid or idiots and come up with a set of standards?
BTW, i didnt call him stupid, i said wot he said was stupid. ;)

[reelmule]

Doug,
I find the thought of a precession stall at a full 1 G RRPM distressing to say the least. In FW the rate of turn is directly proportional to the bank angle. not so in a gyro??IOW's pitch up 10* and roll left 10* and stomp full left rudder and you can complete a 180* turn in 5-6 seconds (or faster) instead of the 60 seconds in a standard rate turn. My question to you is at what rate of heading change does this manuver push the envelope? How do we learn the corners of the envelpe so we don't "GO THERE?"
Walt

[birdy]

With respect Walt, do'n a 180* turn in 5-6 seconds is no where near their limits, no matter wot bank angle your at.
Less than 2 seconds is getn closer, but where ever the limit is, the stick will tell you long before you get there, so dont ignor it. :)

[chuter]

Spencer,

The "Mistakes" poster was the center display at Kelly's memorial service.

[magilla]

Wow,

That's sad.

A man's life should not be measured by the one moment surrounding his death.

Kelly was far more than just a gyrocopter accident statistic.

[karlbamforth]

Magilla,

Excellent posts, This is just what we need. The gyro community should police itself before the authorities do it for us. Its no good moaning about the restrictions after they have been imposed by the FAA , CAA etc.
I wish I could say the same things and get myself across as well as you.

A few years ago I posted a letter saying something similar in a UK magazine, you would not believe the hate mail both I and the magazine received.

[Doug Riley]

Walt:

No one has ever catastrophically stalled a gyro rotor doing a coordinated turn, as far as I know. People do banks past 90 deg., barrel rolls, loops and other wild stuff. Occasionally somebody will manage to get a whip-cracking noise out of a blade as it stalls momentarily (don't make a habit of this).

The only commanded maneuver around the y-axis that we have seen cause a probable precession-stall crash is a high-speed flat "pedal turn." This one has cost a couple people their lives. It's a turn made with appreciable airspeed, a yank of back stick and a stomp of rudder. With the back stick, the tipped spindle "stirs" around in the center of the rotor disk as the frame goes around, feeding in a sustained large, quick cyclic change. It's especially deadly to do this with rudder AGAINST the direction of rotor rotation. Note that the back stick likely jazzes up RRPM, but to no avail.

The same maneuver with no airspeed and neutral stick is the very benign pirouette ("falling leaf") of Ken Brock fame.

Other known causes of frame-induced precession stall are rolls from engine torque ("torque-over") and the familiar PPO ("power pushover"). Common to all of these are prop/engine-generated forces on the frame, that wrench the spindle around with much more force than you or I can apply to the stick.

The rate at which a rotor can digest cyclic pitch change can be calculated. It's a function of rotor mass, lifting characteristics and operating RPM. So, yes, RRPM sneaks in as one factor, but not the main cause.

A low-RPM, massive rotor reacts the slowest, but it also hammers the stick the hardest to warn you to cut it out.

Since the widespread adoption of redrives in the 80's, and the resulting increase in HTL in general, there have been a number of PPO accidents in which the gyro departed from level or climbing flight without warning. These surely happened at normal RRPM. The old Bensens (with less HTL, light-and-fast blades and lower prop thrust) porpoised before going over; loss of RRPM from unloading may have a been a factor in those old accidents.

[barnstorm2]

Magilla, Karl,

With all respect I completely agree with some sort of published stablity standards.

HOWEVER, bolting an HStab on your gyro is CHEAP, EASY, and makes all the sence in the world BUT still some owners are "hard-headed" and don't do it.

I don't see how a self-imposed HStab standard is going to get any more unstable gyro owners to go out and to the right thing for themselves and our hobby if they have not already done so.

Letting these owners just kill themselves and their passingers off is no solution either because we have a major kit manufacturer still pushing these things and mis-information into our market. Therefore the high die-off rate won't reduce the number of unstable machines.

Unless we can remove the sale of unstable kits OR require stability education strong enough to over come what Ron A coined as "Owner Pride" we are at an impasse. (see also my post : http://www.rotaryforum.com/forum/showthread.php?t=11838)

Unstable kit mfgrs and their lies about stablity will posion our hobby until they go out of business or our hobby becomes outlawed or destroyed by FAA over-regulation. Which ever comes first.

If you can come up with a good set of stability standards to inforce I will help in any way I can but how do you propose we inforce these standards on our hobby?

[C. Beaty]

Rapid change of rotor orientation can also reduce rotor rpm. A good amount of energy is required to change the plane of the rotor; it’s a pretty stiff gyroscope and unless the energy required is replenished from inflow, must come from the stored kinetic energy of the rotor.

The pilot is unaware of this energy sink, he commands an aerodynamic servo, not unlike power steering where the engine does all the work via a hydraulic pump.

In the classic forward tumble of HTL machines, low rotor rpm no doubt plays a role in permitting the airframe to run into its own rotor.

[Doug Riley]

Chuck, definitely. The energy to make that shotgun noise has to come from somewhere. The notion that's incorrect, I think, is that loss of RRPM CAUSES the sequence. It doesn't necessarily, but it certainly is part of the fallout.

In reply to Steve Osborne, the moral thing for an instructor to do is to tell any student who proposes to build/buy an unstable machine, in the strongest possible terms, that he should not. If the student persists, the instructor should refuse to take him as a student.

Stability is not some frivolous option like metalflake paint. It is every bit as much a matter of life-death safety as an adequate teeter (a.k.a. Jesus) bolt. No CFI with any integrity ought to allow him/herself to be used in the marketing (or other enabling) of unstable and therefore unsafe aircraft.

Some "tough love" is desperately needed here. It's been lacking all these years.

[C. Beaty]

I expect I could count the number of CFIs on the fingers of one hand who refuse instruction to students intending to fly HTL gyros without horizontal stabs.

Education must begin with the educators, the CFIs; otherwise, there’s not much hope of reducing the smoking hole rate.

[Doug Riley]

Chuck, you won't need a finger for me, since I'm a mere BFI. I do, however, refuse instruction to anyone who will not be flying a stable design. If he hasn't decided yet, I'll give him an intro lesson and urge him to hold off the rest until he has a machine ready (heck, if they take all the lessons now, they'll be rusty by the time they get their machine).

They will get a serious stability talk at the time of the intro lesson.

[karlbamforth]

Magilla, Karl,

With all respect I completely agree with some sort of published stablity standards.

HOWEVER, bolting an HStab on your gyro is CHEAP, EASY, and makes all the sence in the world BUT still some owners are "hard-headed" and don't do it.

I don't see how a self-imposed HStab standard is going to get any more unstable gyro owners to go out and to the right thing for themselves and our hobby if they have not already done so.

Letting these owners just kill themselves and their passingers off is no solution either because we have a major kit manufacturer still pushing these things and mis-information into our market. Therefore the high die-off rate won't reduce the number of unstable machines.

Unless we can remove the sale of unstable kits OR require stability education strong enough to over come what Ron A coined as "Owner Pride" we are at an impasse. (see also my post : http://www.rotaryforum.com/forum/showthread.php?t=11838)

Unstable kit mfgrs and their lies about stablity will posion our hobby until they go out of business or our hobby becomes outlawed or destroyed by FAA over-regulation. Which ever comes first.

If you can come up with a good set of stability standards to inforce I will help in any way I can but how do you propose we inforce these standards on our hobby?

I know what you mean and I don't have all the answers but we (the gyro community) have to start somewhere.
I have looked a few times and it is difficult for a newby to find information on HS and CLT stability without trawling through the various discussions and arguments.
There is often confusing and conflicting information in the same discussion, which means an outsider has to try sort the wheat from the chaff with no previous knowledge.
Can we choose a few knowledgable members to vet information for a dedicated website? We do not want to champion or lambast any particular make but collect all the right information in one place that newbies or students can be refered to so that they can make an informed choice.
Maybe it can eventualy built up to include all that info about how to string blades, do C of G hang tests, or list how to do the stability tests.

As Doug has already said it will come down to the CFI's to make sure that all students are aware of the issues.

Eventually if ppl stop buying unstable gyros, the manufaturers will have to change or go out of business.

We cannot force anything on anyone, but we can try make sure that as many as possible have the right information to make an informed decision, if we do not the the FAA,CAA will force things upon us and as I am sure bpearson will attest, once it is in place it is difficult to change.

[bpearson]

I have looked a few times and it is difficult for a newby to find information on HS and CLT stability without trawling through the various discussions and arguments.


If I was thinking of strapping myself into any contraption that could kill me I would want as much information as possible and would happily trawl through discussion forums. But, in the end you have got to let the individual make his/her mind up.
And which 'authority' do we go with ? Because recent threads clearly show we have a differance of oppinion going on.
Time to let adults make adult choices.

I once watched a pilot fall to his death in an Air Command. He was in the legal profesion and many times more intelligent than me. He had threatened the CAA with legal action if they would not issue him with a permit to fly his gyro. This was after eight fatalities on Air commands in the previous months. I would not have flown that machine for all the tea in China !

[karlbamforth]

Time to let adults make adult choices.

I once watched a pilot fall to his death in an Air Command. He was in the legal profesion and many times more intelligent than me. He had threatened the CAA with legal action if they would not issue him with a permit to fly his gyro. This was after eight fatalities on Air commands in the previous months. I would not have flown that machine for all the tea in China !

Yep thats right and it was probably his so called intelligent adult decision that helped the CAA decide to impose the regulations that you hate so much.
I just think that if the man had easy access to better and easy to understand information he may have made a better decision and be alive now.

All I am saying is if we are seen to be doing something for ourselves, if we can demonstrate that our theories about stability are valid using science not emotion then the FAA/CAA will have more respect for us. May even give us some say in the regulation process.

[barnstorm2]

Yep thats right and it was probably his so called intelligent adult decision that helped the CAA decide to impose the regulations that you hate so much.
I just think that if the man had easy access to better and easy to understand information he may have made a better decision and be alive now.

All I am saying is if we are seen to be doing something for ourselves, if we can demonstrate that our theories about stability are valid using science not emotion then the FAA/CAA will have more respect for us. May even give us some say in the regulation process.

I agree.

We can't count on good decision makeing because obviously people are making bad decisions, passing mis-information and trashing the sport for the rest of us.

.

[bpearson]

if we can demonstrate that our theories about stability are valid using science not emotion

The CAA spent enormous amounts of money on science. And the conclusion is we can fly RAF 2000's, KB 3 copies but not the latest Magni M16. Money well spent eh !

The CAA don't regulate me when I want to fly my powered hanglider but care about my life when it's got wheels.

If we had CHOICE I'd fly a Dominator, but that would never get through sec T. Another load of wasted money !

And, whose science do we go with ? C Beaty, G Greminger, the American guy who came across the pond to act as an expert witness for the CAA and wanted pump handle sticks banned. Please tell me who ?

[barnstorm2]

The CAA don't regulate me when I want to fly my powered hanglider but care about my life when it's got wheels.
?

I suppose there is no way to buy a craft registered in another country and then fly it there?

[Doug Riley]

Now, Brian, one mustn't confuse the law with science. As one of your national treasures put it, the law is a ass, sir.

No engineer or scientist thinks that the RAF 2000 or KB-3 is stable. The regulators just grandfathered these things. The legal notion of "grandfathering" is one of OUR American national embarrassments. It was a legal dirty trick used to keep black Americans from voting in the bad old days. Pure politics and bigotry, no science in sight.

[bpearson]

Unfortunately Doug these craft are deemed ok not because of Grandfather rights. If it were so then the Benson clone we call a Cricket would still be flying without restrictions. This machine originated in the sixties, has hundreds flying, many thousands of hours with a perfect safety record. No performance due to 50" prop but safe.

The RAF is allowed because it is a two seater so they assume that you will get through the training stage intact. The KB 3 clone is allowed because Someone at the CAA said it was ok as it was open frame.

When I say KB clone it differs slightly in that it retains the outboard tank lowdown. My friend has given up trying to get permission for a seat tank to raise the v c of g. But, the CAA say these things are safe to learn to fly on !

I have little confidance in our authorities decisions when it comes to gyroplane stability

[karlbamforth]

I have little confidance in our authorities decisions when it comes to gyroplane stability

And the authorities have little confidence in gyro pilots decisions when it comes to survival.
The authorities FAA or CAA have a duty to make aviation as safe as possible, if poeple keep dying then they will regulate to prevent it. They don't have a choice, it is what they are employed to do, and they will do it like it or not.

So lets start small, give pilots the right information and training to make good decisions. reduce the number of deaths through bad decision making.
Then just maybe we can convince the authorities that we are safe and know what we are talking about, we will then be in a position to lobby for regulation change or restraint.

If we continue with the highest rate of fatalities per flying hour we will eventually be prevented from flying, if not by regulation then by insurance premiums, or just sheer frustration at hearing of gyro pilots dying.

Complaining about the regulations will not change them, proving they are misplaced or ineffective just might.
It should be every gyro pilots aim to raise our position within the aviation community, lets prove we are safe, lets prove we know what we are talking about, lets improve the fatality rate per flying hour by good instruction and training in good effective decision making.
We cannot stop someone from killing himself if that is what he wants to do, but if we give them all the information possible, at least we will have tried.

[bpearson]

And the authorities have little confidence in gyro pilots decisions when it comes to survival.


Thats quite a statement. Cos they regulate what machines we can fly, how we maintain them and the training requirements. What exact decisions are we allowed to make then ?

It was the CAA who deemed the Air Command safe for us all to fly. It is the CAA who are making it so difficult for us to fly modern machines.

Stop seeing them as a reasonable parent of a teenager who if we start acting all responable they might let us stay out a bit longer on Saturday night. Naive in the extreme.

[karlbamforth]

Bp,

I am not going to get into an argument about who is right or wrong.
Lets face it I am not perfect, you are not perfect the CAA are not perfect, who is ?

Its time to stop arguing and time to act, help us improve the situation, help us show how knowledge and training will help, help us show how the regulations can be improved.

Calling the authorities names, saying they are incompetent, saying the regulations are too restrictive or wrong will not change them. Help us prove to the authorities how the regulations can be amended and improved.

You are a passionate about gyros, I want you on side. lets do something no matter how small to improve the sports credibility and change things.

[bpearson]

So lets start small, give pilots the right information and training to make good decisions.

This sounds like it is coming from the mouth of a cheesy politician. Right information ! Whats that then ? Low thrustline, slightly high, H stab, immersed or not. RAF 2000 or KB 3.

Giving pilots information is a really good idea if they could then make a decision based on it.

[Fl90]

Credibility is hard to get. I have witnessed people being chased from this sport two different years at Bensen Days, by a person that uses the same position (if all gyros were stable, the track record would improve, and people would be more accepting of them). One person was a FW pilot that was looking to expand his flying experience. The next year was a man and wife looking for a form of recreation. The wife was frightened by the "airshow", and the couple walked directly to their car and drove away.

As I've said before, it's not just the accident rate that we have to overcome.

[barnstorm2]

FL90 your post seems self-conflicting.

Did this person chase them off or the gyros flying around chase off the couple?

Just what form did this chasing take?

Indeed I agree that for many people to look at a gyro CLT or HTL it still 'looks' unsafe to the average joe but frankly you can't have a much worse PR problem then a HIGH DEATH RATE now can we???



.

[bpearson]

Karl, would you argue with our American cousins that their sport would be improved by implementing our stifling, highly regulated regime ? Because if they lived under our rules then CLT would still be a theory.

I am sure you read the Gasco publication a few months ago. The article about over regulation stopping UK innovation and invention in aviation said it all.

[Fl90]

Tim, for the FW pilot it was, "the unprofesionalism and failure of some participants to recognize the difference between an airshow and a flyin". For the couple, the specific flying at the time they walked under the big tree and looked up/down.

I'm not interested in pointing fingers and throwing names, my point is, to use the publics oppinion as a base for an argument to get someone to make a change, is flawed. There is enough information and reason to work with, to not use the "you're the problem with the gyro sport" viewpoint when discussing stability.

I've made a number of changes to my machine, some good and some bad, and none of them were made with the publics oppinion in mind. I think I have a stable machine now, and when I'm done reading the stability test proceedures (and understand them), I'll find out.

[Chuck_Ellsworth]

Freedom to experiment is one thing.

Ignoring basic aerodynamic principals such as using an HS to improve stability something that has been part of aircraft design almost since powered flight began is not the way to grow a sport such as gyroplanes.

Every fatal crash involving a gyro brings the sport closer to more regulation.

What is wrong with conforming to the rest of aviation?

[pwendell]

What is wrong with conforming to the rest of aviation?

Nothing, and we should. This will not, however, happen overnight. It is a CULTURAL problem, and, as such, will probably take a generation or so to be fully resolved, assuming we all start doing the right things now.

The fact is that on this forum, we are basically preaching to the choir. Those who read these posts and take them seriously are generally people who care about the sport and who want to protect it. They also mostly care about being good(=SAFE) pilots, even if the don't completely understand or agree with what makes gyroplanes stable.

The real problem, as I see it, is those people who never find this forum, and who through ignorance, over confidence, or both are easily swayed by "instructors" who put them in sexy, dangerous machines and show them how "easy" gyros are to fly. These victims might never have had the opportunity to talk with any other gyro pilots or instructors who have other experiences or points of view.

I firmly believe that we must insist that our CFIs train our pilots to high, consistent standards which must include a thorough explanation of gyroplane aerodynamics and stability. I further feel that, like Doug and some others I know already do, all our CFIs must strongly discourage their students from building/flying unstable designs, and should refuse to train them or sign them off if their students won't comply. Lastly, and most distressingly for me, I have come to the conclusion after several years on this forum and learning to fly gyros, that we should find a means to officially censure those CFIs who fail to meet these standards. This is a very small community and anythings that threatens to fragment it is very unpleasant and very possibly damaging in the short term. However, I see no other option if we are ever going to change the culture that is killing us, both individually and collectively.

If an adult, certificated gyro pilot wants to build and fly an unstable machine, that is his/her choice as far as I'm concerned, but they MUST have been given the information necessary to make an INFORMED choice. That information has to be made a mandatory part of their initial training.

[karlbamforth]

This sounds like it is coming from the mouth of a cheesy politician.

Thanks for all your help and encouragement.
End of discussion.

[karlbamforth]

Karl, would you argue with our American cousins that their sport would be improved by implementing our stifling, highly regulated regime ? Because if they lived under our rules then CLT would still be a theory.

I am sure you read the Gasco publication a few months ago. The article about over regulation stopping UK innovation and invention in aviation said it all.

Read back through the threads, we are trying to prevent this happening in the USA.
If we can prove to that we are right and can lower the death rate then maybe we can prevent the stifling regulations.
Then maybe we can start to demonstrate that the regulations in the UK can be safely relaxed a little to allow CLT etc.

[karlbamforth]

Tim, for the FW pilot it was, "the unprofesionalism and failure of some participants to recognize the difference between an airshow and a flyin". For the couple, the specific flying at the time they walked under the big tree and looked up/down.

I'm not interested in pointing fingers and throwing names, my point is, to use the publics oppinion as a base for an argument to get someone to make a change, is flawed. There is enough information and reason to work with, to not use the "you're the problem with the gyro sport" viewpoint when discussing stability.

I've made a number of changes to my machine, some good and some bad, and none of them were made with the publics oppinion in mind. I think I have a stable machine now, and when I'm done reading the stability test proceedures (and understand them), I'll find out.

I am not finger pointing or saying any particular person or opinion is a problem within the sport.
All I am saying is lets educate ppl so that they can make good informed decisions.
The pilots who appeared to be unproffesional or didn't appear to know the difference between an airshow and a fly in, probably did not realise the effect their actions was having on the sport. If it is explained then maybe next time they will realise that they are on show promoting the sport and act a little more appropriately.
We are talking about education here, having the right information to make an informed decision. Witch hunts, finger pointing and blame will simply alienate ppl. We want to improve the sports reputation by willing action from as many as possible.

[bpearson]

What is wrong with conforming to the rest of aviation?

So you would have stopped the CLT pioneers experimenting then and made them conform to flying Bensons ?

[bpearson]

Freedom to experiment is one thing.

Ignoring basic aerodynamic principals such as using an HS to improve stability something that has been part of aircraft design almost since powered flight began is not the way to grow a sport

Not according to the report commisioned by our CAA Chuck. They concluded that H stabs had little effect on stability. Now, you tell me who I should conform to. The CAA ? Please tell me. Because in your ideal world I should be conforming to some standard. Whose ?

When I strap myself in a 737 I expect it to conform to every regulation going. But experimental aircraft are surely that.

[GyroRon]

Tim, for the FW pilot it was, "the unprofesionalism and failure of some participants to recognize the difference between an airshow and a flyin". For the couple, the specific flying at the time they walked under the big tree and looked up/down.

I'm not interested in pointing fingers and throwing names, my point is, to use the publics oppinion as a base for an argument to get someone to make a change, is flawed. There is enough information and reason to work with, to not use the "you're the problem with the gyro sport" viewpoint when discussing stability.

I've made a number of changes to my machine, some good and some bad, and none of them were made with the publics oppinion in mind. I think I have a stable machine now, and when I'm done reading the stability test proceedures (and understand them), I'll find out.


If your not willing to name a name, then why bother saying anything at all?

And look.... Gyroplanes are NOT NOT NOT NOT NOT NOT NOT ..... I said Not, For everyone! If people want to pack up and go home because someone was wearing it out in their gyro at a fly-in, well they were just tire kickers who weren't serious about flying gyros to start with.

Everything that goes on with the PRA.......

Everything that goes on with this forum......

Everything that goes on at gyro fly-ins.......

Everything that goes on nationally with gyro people, flying, accident rates, etc.....

NONE of that should affect or stop a person from flying his or her gyro at home for his or her personal satisifaction and enjoyment.

[chuter]

I'm a bit confused about the difference between an airshow and a fly-in.

As long as the pilot was staying away from the crowd and other aircraft, what's the problem?

I've never flown at a gyro fly-in, but I'm guessing the sponsoring org would lay out the flying and safety rules for the event, and if the pilot stays within the rules, he should be ok...................?

[giro5]

Lets see. Of the 4 fatal accidents I have read about on this forum since the last Bensen Days some had a HS and some did not. But they all had two things in common; the gyros were pusher configuration and they were all flown by people. So should all pusher type gyros be banned? And then when we are all flying tractors, and there is a fatality should all people be banned from flying gyros. The accident records demonstrate one thing. Flying a gyro is dangerous. They are not the safe because of "no stalling" that is a common idea.

[Hognose]

Several Comments.

Peter Wendell says: "The fact is that on this forum, we are basically preaching to the choir."

I wish that were true. On this forum in the last few years we've had: a member perish in a propping mishap; a member crash fatally from a few feet altitude in winds; a member plunge to his death on takeoff in a machine that had a previously pristine safety record. This is utterly apart from the deaths of non-members who were our friends, like the guy who zoomed on takeoff into an apparent low RRPM situation and the high-time CFI who took a stab off because he thought it was unnecessary (maybe it was; we still don't know what got him, but I've always approached troubleshooting by casting a beady eye on the last change made).

For all the heat on RAF, the only one of those mishaps in an RAF was to a machine with the New Zealand stab, and there was no rotor transfer mark visible on the vertical stab, which is not characteristic of the classic "RAF/Air Command bunt".

Ben Pearson says, "according to the report commisioned by our CAA.... H stabs had little effect on stability."

Ben, I believe if you read the University of Glasgow papers, the conclusion is that the H stab has an effect but the vertical position of the thrustline in reference to the center of mass has a much greater effect. I have seen people deny this research, but I haven't seen anyone actually refute it (or make a serious attempt to).

Yes, this had a very direct impact on Section T. And on the subsequent regulations restricting pilots from flying pods until they were experienced, and restricting speeds. I think the speed regulation recognizes something that Dr Houston hasn't really researched, and that currently is ill-documented: the effects of aerodynamic drag on fuselage elements on gyro stability and safety.

I certainly look at a shovel-nosed cabin gyro and wonder what effect that big slanted windscreen has on the sum of moments of that machine, especially at high speeds. Nobody's gone into a wind tunnel to get an answer to this, as far as I know. We all know what the wind tunnel will probably say, but until we do it, we can't be sure.

The reason that Brand X is available and Brand Y is not in the UK (talking about machines designed subsequent to Section T's publication) has much to do with the degree to which the manufacturer or importer is willing and able to jump through the Section T hoops. I understand the MT-03 is available now in Britain. This is a machine that copies enough from the Magni that the Magni would certainly be available if Magni had an importer as willing to slug it out with the CAA as the MT importer has been.

As far as the philosophical issue, what should the government control or ban? I am of a libertarian bent and find the relaxed regulations of the USA, Canada or France more congenial than the bureaucratic restrictions of Britain or Germany. The story of civilization seems to be one of some people wanting to restrict other people's freedom, all the way back. Our FAA takes the position that a knowing person may consciously risk his or her own neck, but may not dice with the lives of others who don't consciously accept such a risk.

To me, that seems reasonable and it helps to explain why some people leave one country and uproot themselves and go to another where they fit in better; my ancestors were British subjects and there but for their sense of adventure and thirst for freedom and opportunity would go I.

The irony of course, is that the American quest and thirst for freedom is largely inherited from our British founders, with a little bit of French philosophy thrown in. And these days, we fight every day to retain the freedoms we have, against people who would take them away for noble and high-sounding reasons. It's all for the children, they tell us.

I doubt there are many of us in the gyro world who do not crave and love freedom. I keep thinking of that fellow in China who had his friends block traffic so he could fly a gyro off the road. China is not only one of the last Communist oligarchies on the planet, but also a culture that places great emphasis on conformity, but that guy manages to fly. The Britons may chafe at the restrictions on them (as much imposed by the PFA as CAA, I think) and if they do, it's because that universal spark of freedom never gives up.

You can be a proud Briton -- or Chinaman -- or American -- and still know your country is not perfect yet. That's one reason we talk internationally, so that we can share what works. The US would never have light sport aircraft if Europe hadn't had JAR VLA and Canada Advanced Ultralight rules. You guys shamed our bureaucrats into it.

Britain's restrictions bring about one very positive thing: the only valid gyro safety statistics in the world. Because Britain is the only nation that has a significant number of experimental aircraft AND requires operators to renew their machine's Permit to Fly and state its hours annually. Those statistics are appalling, by the way; gyro flight there is twenty-seven (!) times more dangerous than flying in general.

There really is a safety problem in among all the noise; that's the point. We have to bring our safety into line with other aircraft. Bear in mind that, statistically speaking, hydrogen-lifted airships had a better safety record than gyroplanes, even after the R-101 and Hindenburg disasters that ended the British and German (and world) development of dirigibles in 1930 and 1937. Yet governments worldwide banned or scrapped (the R101 was government built and owned, and a disaster of a bad design, but the Air Ministry revoked the Permit to Fly of the successful civil R-100 too) their dirigibles forever after those two spectacular crashes.

If we don't want to go the way of the Zeppelins, we need to tighten up our act on safety.

cheers

-=K=-

[Doug Riley]

I think Phil's point was that public perceptions can be way off, and can hurt us.

John Q. thinks gyros are dangerous because (1) there's no "protection" around the pilot (2) it will fall out of the sky when the engine "stalls" (3) it will fall out of the sky when the wind stops... and other silly stuff. So we do have to be protected from mob thinking. The regulators ought to be professional enough to act as a buffer between us and the ignorant.

Bensen Days has rules and procedures. Pilot briefings are mandatory each morning. The procedures, however, are gyro-appropriate. Playing around the fields west of the runway and camping area (where spectators can see you) is OK. The pattern is tight and low, as a gyro pattern should be. What looks to a FW pilot like "screwing around in the pattern" is, in fact, screwing around outside OUR pattern. Most pilots in the air at any given time have radios.

Maneuverable, stall-proof aircraft can have different rules than Cessnas and still be safe.

Airshow: paid entertainers fly; you and the ground-pounders watch. Flyin: you fly and entertain the ground-pounders.

[Chuck_Ellsworth]

"
Quote:
Originally Posted by Chuck_Ellsworth
Freedom to experiment is one thing.

Ignoring basic aerodynamic principals such as using an HS to improve stability something that has been part of aircraft design almost since powered flight began is not the way to grow a sport


Not according to the report commisioned by our CAA Chuck. They concluded that H stabs had little effect on stability. Now, you tell me who I should conform to. The CAA ? Please tell me. Because in your ideal world I should be conforming to some standard. Whose ?

When I strap myself in a 737 I expect it to conform to every regulation going. But experimental aircraft are surely that.


O.K. bpearson I'm all for experimenting and I am also starting to get won over to the no HS group here, after all what could be more comforting than having a former FAA employee representing no stab machines and claiming they are safe.

But first I want to find out what the safety record would be if the H.S.'s were removed from every aircraft in the world.

[Harry_S.]

Uh Oh, you opened the window Steve by printing those three letters...RAF.

Your post makes sense to the experienced RAF pilot but means nonsense or no sense at all, to the non RAF pilot. They just don't know and, I guess they never will know...being as they won't fly in the RAF.

Maybe, just maybe, we have to break or differenciate the RAF posts as regards the experienced vs the inexperienced or the newbee?!


Cheers :)

[Fl90]

Thanks Doug, for taking my post at face value. My point is the base of the arguement. The fact that I fly a gyro is a detractor, for the people that are familiar with my history of activities. Agian, my post was not meant to offend, merely to keep the persuasion focused on more relevent points.

Phil.

[giro5]

Question? If the prop thrust is parallel to the keel and a HS is installed also parallel to the keel is there a significant down force created. If so is it from the swirl of the thrust? Does it matter if the HS is 8-10 inched up or closer to the prop center? Talking about a flat plate HS.

[BigBen]

Is there a place for PRA?

Since almost all gyro CFI's are operating under the graces of the PRA training exemption for experimental gyroplanes, what is the organizations place and position on allowing the "maverick" CFI's to jeopardize the continuance of that exemption by training and proselytizing students towards unstable designs?
Many years back when I was receiving their magazine, I seem to remember PRA was strongly recommending horizon references, less sensitive control ratios AND horizontal stabilizers. It seems suicidally ironic to risk loss of this valuable training exemption when the FAA does crackdown because the students become smoking holes while being trained under the very organizations exemption that knows a safer way.

[WHY]

HI Ben

PRA does indeeed make these recommendations but can only do so on a advisory basis, this type of organization litterally cannot make mandates or or design requirements.

Tony

[Chuck_Ellsworth]

I have been following these forums about gyroplanes for around 15 years.

The only changes that I have observed is there is always a new group of converts to defend the cult culture who are so out of touch with the rest of aviation who are programmed by one kit manufacturer and their sales group.

Until that mindset is no longer defending unstable machines the carnage will most likely continue.

[barnstorm2]

Humm.. That is a good question. Does the PRA have the right to deny a training exemption?

[bpearson]

Until that mindset is no longer defending unstable machines the carnage will most likely continue.

Carnage is a strong word. Plenty of so called stable machines (Sparrowhawks, Magni Mt ) have been involved in fatal accidents. As long as people fly gyros, people will die in them. The no accident utopia you are searching for doesn't exist.

[dragonflyerthom]

This latest accident give strong credence pro horizontal stabilizer. Would the accident have happened if the H/S was left alone. It had been proven as a stabile a/c with it. Such is the problem with the experimental class. Yes carnage is a bit strong. When I first joined this great group of men and women I was scared to death that I would die everytime I flew my gyro. Now I know that it is possible but training has a strong influence and flying the envelope of your particular gyro should keep a gyro pilot safe in most circumstances.

[birdy]

If the prop thrust is parallel to the keel and a HS is installed also parallel to the keel is there a significant down force created.
No. [ solong as the airflow is also parallel to the keel.]

This latest accident give strong credence pro horizontal stabilizer.
Hmmmm, why, we dont know wot happened yet.

Would the accident have happened if the H/S was left alone.
probably, coz it sounds like it had nuthn to do with the missing HS.

IOW Thom, till we know wot caused it, we cant say either way.
A HS wouldnt save you if you lost control linkage, and your machine wasnt trimmed, or if you had a hart attack.

Speculation here is usless.


IF he'd hit a massive sink, and it was HTL, and he had never flown such a machine before, then it would be possable caused by the HS be'n removed, and id be the first to think so.

But we dont know yet, so keep you minds open.


The only changes that I have observed is there is always a new group .......................
I think, to sum extent Chuck E. that the same could be said bout most all other groups of people. Bad apples[ for want of a better term] come and go, and they just keep on come'n, and go'n. ;)

[chuter]

who are programmed by one kit manufacturer and their sales group

Chuck, you're trying to make this about RAF, but this one had nothing to do with RAF.

It wasn't an RAF that crashed, and the pilot didn't learn from an RAF instructor.

[gyrogreg]

Humm.. That is a good question. Does the PRA have the right to deny a training exemption?

The 5209 Exemption requirements are set by the FAA and specified in the text of the exemption. The PRA has been advised by the FAA that it can make no additional requirments and cannot deny an exemption to anyone who meets the requirements as set out by the FAA.

- Greg Gremminger

[gyrogreg]

Question? If the prop thrust is parallel to the keel and a HS is installed also parallel to the keel is there a significant down force created. If so is it from the swirl of the thrust? Does it matter if the HS is 8-10 inched up or closer to the prop center? Talking about a flat plate HS.

Good questions! And there still seems to be so much misunderstanding about how a HS works and what it dows and what it is needed for:

A symetrical airfoil HS mounted on level on the keel DOES have some down force created - even if the prop is also level to the keel. Not as much as if the HS were raqised more up into the prop wash though. (FYI: the mest propwash effect is at about 2/3 distance from teh center of the prop to the outer diameter - that's where the HS will get the mose effect from the propwash.) The HS gets some lift even on the keel by two mechanisms - whether it is enough for your particular gyro takes a little testing to find out:

1) If the prop thrustline is offset from the gyro's CG, the gyro will fly at a keel AOA (keel not level) that presents a an upload or download on the hs - simply becasue the keel is no longer flying level. If the gyro is a HTL, the keel will fly nose-down a bit, and the HS will have a downward AOA and create a download in flight. The oppoistie happens with a LTL gyro - the keel and HS have a positive AOA and the HS creats an upload.

2) The airflow into the propeller is converging, being drawn in by the reduced air pressure created in front of the prop. Behind the prop, where there is higher than ambient air pressure, the propwash expands. This expansion creates some outward propwash flow that provides a propwash induced downloading AOA on a HS mounted on the keel. This expansiton effect does not affect a HS mounted centered with the prop. Still, the best propwash effect on the HS is about 2/3 distance from the prop center.

As described in (1) above, a HTL gyro automatcially creats some download on the HS the HTL causes the gyro to fly a bit nose down.. From a stability standpoint, flying nose lower than normal is destabilizing. We depend on the HS to raise the nose back to level to reduce the instablity caused from the HTL nose lowering moment. Obviously then, the keel level mounted HS will not completely eliminate the HTL nose-lowered AOA of the airframe from this effect alone - it cannot completely compensate for the HTL moment if the downloaded HS moment is dependent on the nose-down attitude. But, this effect combined with the expanding propwash effect can provide that the HS can compensate for a HTL - if the HS is properly installed and configured.

How can we augment the effect of the HS - the rest of your question:

- If you need more HS download to balance a badly ofsset prop trustline, move the prop up into the propwash for more effect. (2/3 from the prop hub for most effect.

- The HS can be angled with a bit of downward AOA for more downloading if needed to further balance the HTL moment.

(But, if you are needing to use both these two mechanisms above, I'd suggest you might consider reducing your prop offset so it is easier for a reasonable HS to compensate.)

- A better way to make the HS more effective is to make it an airfoil shape - not a flat plate. The lift curves on an airfoil shape are almost twice as strong as a flat plate - twice the value for the same size HS. Also, a flat plate has really abrupt stall characteristics - if you got into a real need fro the HS to be really effective - say in a very strong gust of wind or the a buntover precursor strong nose pitch down, you don't want the flat plate HS to stop working just when you need it the most!

- Position the HS further aft of the gyro's CG - far back on the keel! Several major advantages come with mounting further aft:

+++ The moment arm (lever arm) of the HS is longer - requiring actually less download for the same static stabilizing effect. Less download means less additional load on the rotor - more efficient! - - less fuel, more performance!

+++ The propwash has expanded more further aft of the prop - providing a bit more helpful downloading if you need it for a HTL balance.

+++ The DYNAMIC dampening effect of the HS is improved by the square of the moment arm from the CG - this is more effective on the dynamic stability than it is on the static stability! Dynamic stability is important - it tempers the gyro from pitching fast enough to induce a buntover or precession stall of the rotor, and it will dampen any PIO before it even starts - without thye pilot even be aware of it - essentially, a HS mounted far aft is almost a guarantee against PIO, and probably for any other static instability event!

The reason the HS mounted further aft is more effective dynamically, than even statically is that it has the advantage of a longer moment arm like for static reasons, but the longer tail imparts more vertical velocity to the HS when teh gyro is pitching. This increased upward or downward velocity, increases the AOA of the HS due to the relative wind on the HS - the increased AOA creates more lift of the HS. AND this more lift is the greatest at the point in the pitch movement where the pitching is fastest. In other words, this HS, on a long tail, creates an opposing moment to the pitch movement at just the right timing or "phase" where it is most effective. (The problem with a pilot trying to do this, is that such pitch motions are so fast that the pilot cannot keep up, the pilot can easily put corrective inputs in the wrong "phase" - at the wrong point in the movement - and thereby exacerbate the movement - possible PIO or straight buntover!

When you have finally committed to taking advantage of a HS, I would just do it the best you can. Then, you will not have to ask a lot of questions worrying if it will prevent a buntover or PIO - very likely it will if you don't try to just get by with something half-way:

Use a real airfoil. Make it as large as practical. Mount it as far aft as practical. If you need it to balance a very high prop thrustline, position it a little higher than the keel to take more advantage of the propwash. If you need it to balance a very HTL, add a little down AOI for some additional download. (But, for these last two, if you need that much HS help to correct a HTL, consider improving the thrustline - you may really be starting to impact the performance and efficiency of the gyro!

Now I can just hear people starting to cry -t will be toos stable, it won't maneuver, it won't be any fun! [b]BS[/], That is a FW analogy that does not apply to a non-fixed rotor gyro! The HS stabilizes the airframe so it flies true as an arrow to whatever flight path the gyro files in. The stabilized body does not create enough lift to affect the flight path much at all! The rotor is what controls the flight path, it is doing all the lifting and work. And, on a non fixed rotor gyro, the pilot has full control of the rotor right in his/her hand. When you move the rotor, believe me, the gyro sill follow. And, if the airframe is stabilized (by a good HS), the airframe will point directly into where the rotor takes it. A side benefit of this is that the attitude of the airframe then gives the pilot a precise cue as to what the gyro is doing - for more precise maneuvering too!

In an gyro with an unstabilized airframe, the rotor still does all the lifting and work of maneuvering. But, the unstabilized airframe body may be swinging around under the rotor so as to feel a bit more like it is "really maneuvering"! But, in fact, the flight paths are probably the same, just the body is swinging around a lot more - like some carnival ride! - not truly maneuvering like that! And, when the body is swinging around, the airframe attitude cues to the pilot are all screwed up - if the nose is rising is it doing it because the flight path is rising, or the body is just swinging up! Hard to tell, takes a lot of experience in such gyros to ignore what the body pitching and attitude sis doing and respond only to the G-Loads you feel in the seat of your pants. (It takes several hundred hours of flying to develop a good "seat-of-the-pants" G meter in your butt! That is one contributing reason why lower time gyro pilots have more fatal accidents - where pilots with high time in that same "unstable" airframe have lived and learned through the dangerous period and are now flying by the "seat-of-their-pants".

If you want a highly maneuverable gyro, just keep it light and short - inertia is the main element in high maneuverability of a gyro! But, on such high and short gyros, the highly effective HS is even more necessary because the airframe pitching rates can be so high and fast! Tech talk - for high and precise maneuverability: You want a light and short gyro so it will have low Moment of inertia and be able to pitch at a high rate. You want the HS to dampen any oscillations within 1/2 cycle so that high rate of pitching will not overshoot, will not oscillate beyond 1 damped cycle (critically damped). This is how you make a gyro maneuverable - and it is how you make even that highly maneuverable gyro so precisely maneuverable and immune from all the stability problems!

Bottom line, don't worry about how much you need - do the best you an with a HS. Then, if you just have to feel the excitement of an unstablized airframe, start reducing the HS power slowly so you have time to get the seat-of-the-pants G meter calibrated. But, I would bet almost any money, that once you are flying a truly stable gyro, you won't go back. It may be extra dangerous to back up on stability!

- Greg Gremminger

[barnstorm2]

Thank you Greg!

That takes the option off of the table of having the PRA withhold exemptions from trainers that don't properly educate students on gyroplane stability.

Outside of a strong public information campaign do we have any other option for trying to assure gyro consumers and students understand the implications of stability?

Now that we have 2-place trainers and a good selection of known good stable designs and reliable kits there is no reason we should not have a BETTER safety record then the rest of ultralight/sport aviation.

The principle thing making our safety record back and jeopardizing our sport is the persistence of ONE major kit manufacturer to sell unstable gyroplanes and propagandize and lie about gyroplane stability.

I am not staying unstable gyroplanes are the only thing that has ever killed a gyro pilot or that it was a factor in this case (we just don't know yet and may never know) but if we remove unstable gyroplanes and people with a mis-understanding of the physics of gyroplanes from the equation we have the safest craft architecture on the market and our safety record will float right to the top in short order.

Can we count on a fair assessment of this accident if the gyroplane resource on this case is a RAF rep?? I don't know this person so perhaps someone who does can give us some insight.

I guess our only hope is to wage a public information campaign and hope the sale of unstable gyroplanes are so greatly impacted that this company changes their ways or goes out of business.

Any other suggestions?





.

[gyrogreg]

I guess our only hope is to wage a public information campaign and hope the sale of unstable gyroplanes are so greatly impacted that this company changes their ways or goes out of business.
Any other suggestions? .
The public information campaign is what a lot of us have been trying to do. This is what you and the rest of us are doing in this forum. Unfortunately, the people who might need the information are probably avoiding these discussions.

The major reason myself and a lot of others went through the trials and work of developing the ASTM gyroplane standard was to influence the public with a credible "consensus" derived standard. The FAA told me before we decided to actually do this, that something "had to be done" about the gyro accident rate! They told me they did not know enough about gyros to know what to do, so no one would like what they did if they had to do something!

(The FAA Rotorcraft Directorate in Ft. Worth - the people who's actual FAA charter is to improve safety in Rotorcraft, told us (paraphrased) "gyros are too unsafe for us to get involved". Their bet was that there was so much dissention in the gyro community over stability that we would never be able to develop a "consensus standard" anyway! So, they did not even want to help!)

But, FAA in Washington (Sue Gardner - SP NPRM Project Manager) agreed with us that the development of a "consensus standard" should be the approach we should take - too help influence the market and manufactures to safer gyros. The theory is that, even though the ASTM standards are not required for gyros at all - because the Rotorcraft directorate vetoed SLSA gyroplanes - just the existence and promotion of a gyroplane standard should influence safety improvements.

Lo and behold, even RAF and all participating ASTM gyroplane subcommittee members voted for the gyroplane standards! Lo and behold, we beat the odds. The FAA dogs have been held off – for now! Time will tell, but the clock ticks another click with every fatality – and this latest one was one of their own, so I’m sure the “dog’s” ears are twitched!

Now, ASTM owns these standards (copyrighted) – because their facilities, processes and credentials were used to develop them. They meet the Congressional definition of “consensus standards”! But, because ASTM understood the real safety reason we were actually developing the gyroplane standards – we were not really doing it for SLSA reasons because SLSA gyroplanes were not allowed! – they allowed us, the PRA, to freely publish the all-important gyroplane stability criteria – in the interest of improving safety in gyroplanes – our real intent! That is part of the public information program I have been promoting for years now!

There are efforts, there are standards, there is the concern that the FAA might “do something” if this doesn’t work. We have the FAA’s endorsement for this approach. But, it is so damn frustrating that the politics and bickering and blind minds are just not letting the true physics and science and understanding spread among those who need it most!

I am still one of the believers – gyroplanes have the potential to be one of the safest, if not the safest, aircraft in the air. The potential safety attributes of slow and short landings, high maneuverability without concern for stalls, almost immunity from wind turbulence, etc., are entirely within our grasp. It’s this damned “tailwheel” mentality and rogue culture that is keeping this sport from its real potential and destiny. I have some heart though – slowly people are converting, more gyros applying real aerodynamics and stability are emerging, and more new people are studying the issues before “drinking the cool aid!”

- Greg Gremminger

[magilla]

Been gone for a couple days taking my annual IP checkrides...

I had a post I wrote last night and then deleted...too inflammatory, so I'll try again.

It was about the term "Experimental" in aviation, and how it is associated more with the "Darwin Awards" than the Space Program in our gyro community.

After the 30's barnstorming, "Experimental" in aviation was directly associated with the term "Extensive Research" and flight testing was synonimous with "Calculated Risk." Hundreds of geeks with slide rules and Ph.D's in aeronautical and aerospace engineering were arguing fine points about control forces and stability vs. drag and airspeed. Look at all the bloody charts NACA produced on stall regions of non-symmetrical RW airfoils. There was no guesswork there, folks...

But they alone were not responsible for the designs that made the greatest impact and advances in FW or RW aviation. Designers quickly realized they needed input from the pilots to make the aircraft faster, more maneuverable, and ergonomically better and safer to fly.

Soon, the term "Experimental Test Pilot" in the military and professional circles came to mean the best of the best, and smarter than the rest, with extensive training at Pax River, MD. They were graduates of the Naval Test Pilot course. They were not just good seat-of-the-pants pilots, they had the aerodynamic background to understand the areas they were testing. And the testing was regimented. "Fly at an altitude of 10,000 feet and measure fuel burn at 100%, 90%, 80%, and 70% throttle for 30 minutes apiece."

Am I somehow painting a rosy picture of "experimental" aviation? sure. But I want to make a distinction between true experimentation (which includes learning from mistakes, not just repeating them and arguing the same points over and over) and "backyard engineering."

We all need to strive to be as professional as those Pax River test pilots.

Experimental Test Pilots don't just up and decide to take a vital component of longitudinal stability off their aircraft and go fly on a marginal day. They just don't.

Birdy - you are right. There is NO WAY to make the assumption that because he did not have an HStab, he crashed. But you gotta admit that it wasn't necessarily a smart thing to do. While there are no "smart" police, the nerds have proven beyond a shadow of a doubt that HStabs in the correct position and of the correct size are critical to preventing PIO/PPO.

The fact is, no matter who investigates the accident, and what the final cause, even heart attack, the removal of the HStab will still be listed as a "factor" in the incident. No way around that one, Kimosabe.

The preliminary details of this accident make it sound to the casual bystander more like a "Darwin Award" epitaph than an unfortunate accident in the annals of "Experimental Aviation."

That does not diminish the fact that we lost a life, and a fellow gyro brother who by all accounts was well regarded as both a pilot and individual. What I am saying is that he took a stable machine and knowingly reverted it to a previous, less stable configuration.

That's akin to giving up the 4-wheeler and bringing out the old 3-wheeler even though you haven't ridden one in a while. And even though it may have been a faulty tire that caused your death, it will still be logged in the statistics of "Three Wheeler Fatal Accidents." That's the closest analogy I can think of that fits. Regardless, it was definitely a step in the wrong direction.

LEADERSHIP

Just like the sports athlete that becomes an icon for the youth of his generation, however unwittingly, and regardless of his own wishes to the contrary - A pilot, ANY pilot, that accumulates 10,000 hours has to understand he is a role model for the rest of us amateurs.

There is a responsibility you all take on when you become a pilot, and it's not all just about you being able to selfishly do what the hell you want, whenever you want, damn the torpedoes... You need to come to the realization that "It ain't all just about you"

You are setting the example for the rest of the community. And in our gyro community, it is especially important. We need to regulate ourselves, and attempt to sway others in our community to meet the minimum standards.

Believe me when I tell you I am libertarian in nature, and don't like external regulation and micro-management in what is a pure leisure activity.

But internal and self-regulation is OK. I am all for the "team" mentality. We need to do more of the sports team psychology stuff - and more of the Chris Carter's taking Randy Moss's under their wings and making them conform to the team rules...

The bottom line is:

The gyro community is more important than you as an individual gyro pilot

If you don't agree, then fine; but don't continue to be part of the dialogue and the cacophony of noise in the background - just please go away and do your own thing.

My point is, if we don't take steps toward self regulation, the jumbo jet experts in the FAA are going to wield their heavy, brutish hand and mandate stability for us. And we will not like the external regulation, because we will not be able to have any input - we're too busy squabbling like a bunch of looneys over the fact that an HStab increases stability. How on earth do you expect them to take us seriously?

Karl Bamforth IM'd me, and asked about setting up a website with stability charts and links to graphs, etc. I think it is a great idea as a source for unbiased information on stability, and design practices we should all strive to meet.

My last point:

WE LIVE IN THE COMPUTER WORLD. WE HAVE AUTOCAD. THERE IS NO EXCUSE FOR THE PRODUCTION OF UNSTABLE AIRCRAFT.

Do you not think we should lobby the PRA / FAA to take 10 designs and put them through an autocad wringer and test the flight stability envelope? I sure do.

And after we have more conclusive evidence about which design factors increase stability, we can make true experiments, based upon math, to increase performance, as opposed to just guessing because the seat of your pants tells you something.

And if you want to strap a JATO bottle to your station wagon and let 'er rip, then you can join the Darwin Award nominees, and leave the "Experimental" part to those of us who aspire to be professionals.

Again, sorry about the length of this post.

Leadership means we need to set the example. Stand up, self assess, and do the right thing, whether or not anyone is looking.

We sure need some of it now.

Edit - thanks for the post on ASTM standards, Greg. Looks like you understand that leadership role... I applaud your work and your efforts.

[karlbamforth]

Magilla, excellent post, once again I find myself wishing I could compose my thoughts onto paper as clearly as you.:hail:

I have PM'd a few members asking for advice and help in producing a website to promote safe gyro operations and to provide a place to put the various essays, graphs and great links that seem to get posted time and again.

When a newby asks, how does it fly? what turns the blades? can it hover? we can direct them to one place to answer most of the basic questions.

This is our sport, we all need to work towards safer operation and a better reputation, failure to do so will force the authorities to take action. When they do so, it will be heavy handed and over the top.

[Ron Marlett]

Carnage is a strong word. Plenty of so called stable machines (Sparrowhawks, Magni Mt ) have been involved in fatal accidents. As long as people fly gyros, people will die in them. The no accident utopia you are searching for doesn't exist.


Agreed! You will always have crashes, just like every other type of craft that leaves the ground. The Gyro community has what I think is a higher than normal accident rate. How many experimental aircraft forums have a flower fund? This is the only one I have ever seen(but I don't get around much).

If you look at the crashes over say the last 5-10 years, and remove all the types that are know unstable/high-thrust/no-stab from that list, the accident rate gets pretty low.

Now of course this comparison dosn't take into account the number of craft flying, actual cause of those accidents ect, but it does get one wondering what the gyro community would be like with more stable aircraft. If you look at accident causes in other types, they are usually as a result of power plant failure or pilot error or some mechanical problem. Most have an answer, usually because the pilot is alive to tell the tale. Or in other words, because they rarely just fall out of the sky, the general stability and controllability of the aircraft is not usualy the first thing brought up when people ponder the cause of a fatal crash.

How many wonderful people would still be with us to contribute and pass along their love of autorotative flight to others? How many new and interested people would have joined this hobby instead of being talked out of it by just about anyone involved in any other form of flight? How many lurkers are there on this forum who have held off on their decision to build/buy/fly a gyro due to the regular fatatality notices and discussions posted here?

:rip:

Ron

[Vance]

Hello Karl,

I agree that there should be information about how gyroplanes fly and what makes them fall out of the sky. Having it in one place is important for people who are excited to get into the air.

I think it should have a list of instructors.

I think it should have a list of manufactures.

I think it should have information on safety.

I think it should have links to gyroplane sites.

I think it should have information on stability.

I feel it should have information on how gyroplanes fly.

Classified ads would be nice.

I was just on the Popular Rotorcraft Association web site and it has all of these things.

That is why I am a proud member of the PRA.

I suspect that if you contributed it could become more useful internationally as far as instructors, regulations and such.

Thank you, Vance

[Harry_S.]

Can we count on a fair assessment of this accident if the gyroplane resource on this case is a RAF rep?? I don't know this person so perhaps someone who does can give us some insight.


.



That sounds like sour grapes to me, Tim. Sounds like something from an anti RAF guy.

I for one have confidence of his integrity in this investigation. Who knows, there may be other knowledgeable persons involved?!


Cheers :)

[bpearson]

Hello Karl,

I agree that there should be information about how gyroplanes fly and what makes them fall out of the sky. Having it in one place is important for people who are excited to get into the air.

I think it should have a list of instructors.

I think it should have a list of manufactures.

I think it should have information on safety.

I think it should have links to gyroplane sites.

I think it should have information on stability.

I feel it should have information on how gyroplanes fly.

Classified ads would be nice.

I was just on the Popular Rotorcraft Association web site and it has all of these things.

That is why I am a proud member of the PRA.

I suspect that if you contributed it could become more useful internationally as far as instructors, regulations and such.

Thank you, Vance

And if you look on the BRA site Karl you will find a link to all of this and more.
Now for gawds sake get yerself a gyro built and start enjoying probably the best sport in the world.

[C. Beaty]

Spencer, you do have a way with words; that was a cogent and well-written post.

I suppose you’re aware that Rusty Nance, the new PRA president, has a background that closely parallels yours. Rusty is a full time SCNG instructor/test pilot, flying AH-64s.

[barnstorm2]

That sounds like sour grapes to me, Tim. Sounds like something from an anti RAF guy.

I for one have confidence of his integrity in this investigation. Who knows, there may be other knowledgeable persons involved?!


Cheers :)


No, If it were anti-RAF sour grapes I would be staying it is NOT going to be a fair investigation.

What I am asking is if anyone knows this guy and can provide some insight to his knowledge of gyro stability physics and his character because of the OBVIOUS case of a potential conflict of interest.


.

[Chuck_Ellsworth]

Barnstorm, do you mean the guy that wrote this?


" I have made a cognitive decision that I will not teach in any gyropnae unless it has a stabilizer or stablilator. Not that the RAF2000 without either is unsafe because we know there are quit a few pilots out there that have flown them without either/or for thousands of hours safely. But I am a firm beleiver that "TRAINING" is the key to successfully flying any aircraft, not just a gyroplane. "

Maybe insufficient training is what causes these stabless machines to mysteriously fall to the ground?

By the way reading that post I'm really puzzeled, if the RAF is not unsafe without an H.S. or Stabilator why won't that guy train in a stock RAF?



Strange position that.

[karlbamforth]

And if you look on the BRA site Karl you will find a link to all of this and more.
Now for gawds sake get yerself a gyro built and start enjoying probably the best sport in the world.

Sounds great mate will save us a lot of heartache and work. Would you publish the link to the BRA website please, specifically to the areas that reference stability, safety, how a gyro works, Horizontal stabalisers.

BTW I am a member of BRA eagerly awaiting the June 06 edition of the magazine which was promised to be with us by last December.:confused:

[bpearson]

My computer skills aren't up to publishing links that you can just click on but anyone can find the BRA site and the PRA site is on the links.

IMO Tony Wilks has done his bit for the BRA magazine. To produce a high quality mag like he does takes an incredible amount of hours. It should be out soon but he is trying to finish his Magni so time is scarce.

He is always on the lookout for articles. Rejects all mine though...........

[gyromike]

The British Rotorcraft Association (http://www.gyroplanes.org/).

[karlbamforth]

Thanks Mike,

I am quite suprised so see that there doesn't seem to be much information about gyro stability, safety, HS etc. Maybe its just me that can't find it. I agree they do have links to other sites, the PRA website in particular is very good in these areas. :first:

[giro5]

Greg G. Thank you for discussing my question. If I understood another post you made then for gyros is the only options; private pilot with a gyroplane rating, private pilot SEL flying experimental, or ultralight. No legal light sport pilot or just no legal light sport gyroplanes??

[gyrogreg]

giro5 - my clarifications in BOLD below - greg


Greg G. Thank you for discussing my question. If I understood another post you made then for gyros is the only options; private pilot with a gyroplane rating, private pilot SEL flying experimental no passengers, or ultralight. No legal light sport pilot - YES! You can get a Sport Pilot certificate with a gyroplane endorsment - same as airplanes, etc. or just no legal light sport gyroplanes??

You can also get a gyroplane SP-CFI certificate, a Commercial gyroplane rating and a normal gyroplane CFI rating! The only thing you can't do is buy a fully-built SLSA gyroplane! - Yet! After Jan. '08, until individual manufacturers get a dispensation approved from the FAA, you will need to build 51% EXPERIMENTAL AMATEUR BUILT gyroplanes. If a manufacturer is able to get the exemption from the FAA, that would presumably allow you to buy an Experimental LSA (ELSA), essentially fully-built by the factory. Those factory built gyroplanes, if the FAA approves the manufacturer's petition, will be required to meet and comply with the gyroplane ASTM standards. At this time, only Sparrow Hawk has petitioed for this exemption. I expect Xenon USA will soon petition too! - Greg

[BigBen]

The 5209 Exemption requirements are set by the FAA and specified in the text of the exemption. The PRA has been advised by the FAA that it can make no additional requirments and cannot deny an exemption to anyone who meets the requirements as set out by the FAA.

- Greg Gremminger

Greg:
Can you refer me to the PRA Advisory Guide mentioned in the exemption. It appears on it's face that the PRA reviews an application based upon it's conformance to this guide, thus giving the organization some power to require a minimum stability. It seems counterproductive for the FAA to then require the PRA to turn a blind eye towards the organizations consensus of a "safe" gyroplane and mandate issuance of the exemption. I make these comments in the absence of knowing what is in the guide and in full respect for your knowledge of the details and your exhaustive efforts in helping the gyro community to be safer. It just seems to be a potential liability trap for the PRA and a blind canyon in the efforts to improve our safety record...thanks again for all of your help and straight answers.

[birdy]

And there still seems to be so much misunderstanding about how a HS works and what it dows and what it is needed for
No missunderstanding here Greg, thats why i rote;
No. [ solong as the airflow is also parallel to the keel.]
A flat plate wont apply any forces untill the airflow deviates from parallel to its surface.

I know you know that, ;)

[bpearson]

Thanks Mike,

I am quite suprised so see that there doesn't seem to be much information about gyro stability, safety, HS etc. Maybe its just me that can't find it. I agree they do have links to other sites, the PRA website in particular is very good in these areas. :first:

Difficulty is Karl there are no real agreed solutions within the BRA and maybe thats a good thing. And even though the chairman has a vested interest in a brand of gyro he will not give his views on how to best achieve stability, which is how it should be.

Although we are forced to work with Glasgows report (limits the choice of machine), turn up at the AGM and listen to the dissent. I doubt that it is in the best interests of the organisation to start putting down on paper what makes a gyro stable. Maybe links to other organisations is the best way out given our current climate of litigation.

Back in the days before factory built machines the average build time for a gyro was three years. During that time you will find yourself gathering an enormous amount of information from other pilots and builders. Of course it was up to you what info you took on board.

[Xenon-designer]

Hi to Greg, and all.

As you asked me to get involved for ASTM, i read all this subject that appears to be the most touchy one.
I fully 100% agree with you about stability facts.
I would like to say that in Europe we do have some documentation helping us calculating right proportions on the proper design of an HS, CG and thrust lines...
For my point of view as a very experienced ingeneer and manufacturer, we must not keep flying gyros without an HS. Try cut shorten or put closer the tail of an aircraft and we'll guess the result. And so whatever the pilot skills. Updating machines is not a problem, and this should be taken seriously.
Here in Europe, we have to face very strict regulations and safety standards, as well very turbulent and high winds. A naturally stable aircraft will help to keep you in the right flight envelop.
You can count on me to push developping standards and focusing to reduce accidents.
In general aviation design, you find basic rules about thrust line, CG, tail surfaces...that are fully applicable on gyros. It will be fruitfull to meet in SnF, and take time to exchange those important informations, and come up with usefull test procedures and design targets. I'll bring with me for SnF a couple of them to show you.

[chuter]

GyroMike,

Mike, in another thread you said:
I have no hard evidence one way or another, but in talking to some folks close to the investigation it appears that the gyro pancaked in hard and flat, not bunted over. Parts were bent downward, not forward, indicating (to me at least) that he may have simply not had enough altitude to avoid mechanical turbulence/shear from slamming him into the ground hard enough to break an axle. Add in a 25-30 mph tailwind to his airspeed and it would make Ken Wallis's tumble look tame by comparison.


Can you say who you got this info from? That doesn't seem to match the NTSB report that says he nosed in at about a 60 degree angle.

Thanks,

[gyromike]

Michael,

The info I have is merely hearsay and second-hand info. It may just be speculation.
I was hesitant to post it on the other thread because of this.
I think it would be best to just wait for the final report.

[birdy]

Hmmmmm............... a forum admin deleating a members posts coz it contained the word idiot in relation to the actions of the deceased, then he goes ahead and posts confusing and apparently missleading info bout the 'event'.
Hypocrisy?


This should get me banned ;) :)

[Friendly]

Birdy
Its called showing respect to the deceased. There is no need to get ugly. You are too well respected here yourself for that.

[dragonflyerthom]

Is this the gyro that had the H/S removed and then crashed?

http://www.youtube.com/watch?v=sGtPy3__jkQ

[Timchick]

That's it Thom.

[Doug Riley]

When considering the possibility of a PPO, the weight of the blades makes a difference. Those look like Dragon Wings, which are pretty light. The heavier the rotor, the higher the CG. The lighter the rotor, the lower the CG and the more height of thrustline over CG.

McCutchen and extruded blades are massive and bring the CG up all by themselves.

[chuter]

Kelly had 23 foot Dragon Wings, and his mast was pretty short, so he might have had more of a HTL than you might think.

[dragonflyerthom]

Still it was a nice gyro. Looked good and seemed to fly great. Sorry it crashed. I sure am wondering on this one.

[Doug Riley]

The 23's, especially, are pretty light. As Michael says, a short mast means the mass of the rotor has a short lever arm and therefore doesn't "count" as much in determining CG height.

It's hard to tell from John's video whether he's intentionally putting the nose down before a climbing turn, or whether the nose dips by itself as power is added. If the latter, it's a sign of HTL -- but that is not likely to have been a serious problem as long as the HS was there.

My first gyro was a Bensen VW similar to this one, except it had a steel outboard tank and no HS or rockguard at all. It was anemic enough that I just chugged around at 50 mph with no yank, and not much bank. The nose did seem to rise a little when I hit an updraft (an unstable reaction). I was extremely wary of "zero G," having been scared half to death by all the accidents.