No stab and no hands

[Steve Osborne]

If I remember right Vance was flying near a mountain or big hill what ever you want to call it when this happened. Last year I went to a fly in with Larry Boyer at Mifflin County, the airport is nestled between to mountains and the winds were very mild as long as we stayed in the middle of the valley if you ventured close to the side it would kick the crap out of you. Mountain or uneven terrain flying is totally different then flat land and there are course available on what to avoid.

 

[barnstorm2]

When I was still a student pilot flying an AC447 gyro over the flat lands of Ohio the winds forcast said that the winds would not get over 5mph for that day and the next.

20 min after takeoff I found myself away from the airport and in 25mph winds gusting to 35.

An experinced pilot should know better then to trust the weather man or his engine.

.
If you can find a way to design out flaws in the weatherman more power to you man. Your apt to get quite rich.

Meanwhile, it is just common sense to design out flaws in airframes and designing out instablity is quite easy if you know the basic physics. Add a STAB!

.

 

[Brent Drake]

I oncew had a downdraft severe enough to drop my balde speed from 300 to 250. I took alot of my height to get the blades back to flying again.
Dennis said that downdrafts have no effect. I think they do. when falling in a downdraft, there is no great uprush of air to keep the blades at the rpm of when the draft started.

 

[Harry_S.]

My two posts, I thought pertained to TRAINING. Maybe I should have had put 'em in the TRAINING Thread?!

I'm outta this thread...for now.


Cheers

 

[pwendell]

As Jim Mayfield used to use in signature line, "Stability is not an opinion". Stability is a fact that can be measured and determined by the techniques developed by "pencil pushers" and can be rigorousely tested in the real world by test pilots.

I say we kill this thread and this topic until someone can add some new facts and/or testable hypthoses that can explain why Gyros with a thrustline above the center of mass (HTL) and without adequate horizontal stabilizers are not both statically and dynamically unstable and therefore inherently prone to PPO and much more succeptable to PIO. The fact that some people have flown them for many hours without dying does not prove that they are stable without a theoretical framework that can explain why and that can be tested and verified.

If someone wants to fly an unstabbed RAF or "Classic" Air Command, I have no problem with it, but don't claim it is "Stable" or "Just as safe as a Dominator" unless you are willing to do the mental work to back it up with basic physics and aeorodynamics. Otherwise, this is all just a waste of time that only serves to give some people more credibility than they deserve.

 

[Doug Riley]

I'm right behind you, Harry.

A parting shot (of course):

PPO is NOT (repeat NOT) a loss-of-RRPM problem. Yes, loss of RRPM can be a problem, but it is not the SAME problem as PPO. PPO (and its cousin, drag-over) can only happen to an aircraft that has the forces on the frame arrayed in such a way that, once G's are reduced, the situation feeds on itself and the aircraft flips forward. It's this flip, powered by prop thrust or frame drag, that is the killer in a PPO, not low RRPM.

This is important, and if you don't understand it, you don't understand the dangerous nature of PPO. PPO is consistent with FULL RRPM. It happens in a time interval that is too brief for RRPM to decay much at all.

When the rotor's angle of attack is drastically reduced, the rotor thrust is INSTANTLY reduced along with it. The rotor thrust does not wait for the RRPM to decay before it declines; the rotor thrust declines RIGHT NOW.

Why? Because a reduction in disk angle of attack reduces the individual angles of attack of each blade, all the way around the circle. IOW, from the point of view of the angles of attack of the individual blades, reducing disk AOA is EXACTLY the same as dropping collective in a helicopter. Draw some vector diagrams of advancing and retreating blades and see for yourself. I didn't understand this for the longest time (until I pushed the hated pencils).

Perhaps a failure to recognize this fact is what leads to misunderstandings about the nature, and curability, of PPO and drag-over. If your gyro goes upside down in a second or less, RRPM will be have been irrelevant. The gyro WON'T go upside down if forces on the frame are arranged properly by design.

 

[Harry_S.]

You snookered me Doug.

No comment.


Cheers

 

[barnstorm2]

If someone wants to fly an unstabbed RAF or "Classic" Air Command, I have no problem with it, but don't claim it is "Stable" or "Just as safe as a Dominator" unless you are willing to do the mental work to back it up with basic physics and aeorodynamics. Otherwise, this is all just a waste of time that only serves to give some people more credibility than they deserve.

Speaking of tag lines, I wish we could make this (text quoted above by pwendel) the tag line of a few posters around here. That would solve the problem nicely.

 

[DennisFetters]

Stan, I agree, I don't want to argue. That's what I said at the beginning of the thread, but then the insults start from some of the others and it's hard to keep on track. So many people here are asking me to explain this and explain that, I can't possibly answer them all. SO I'll answer you here, and then there is just no more purpose for me to continue beating a dead horse with the others.

Dennis: I enjoyed my HTL Air Command very much. I taught myself to fly it and I flew it in all kinds of wind and it served me well. I then had the same experiences in my RAF2000....
I also loved flying that machine. I flew with confidence but always had that thought in the back of my mind about an unloaded rotor,,,but and I honestly believed my type of flying would make it VERY unlikely that I would encounter such and event.

I'm glad you survived teaching yourself to fly a Gyroplane. You are very lucky. I strongly disagree that you tried, as you may remember in the assembly manual and letters we sent out. But, lucky you, thank God.

The discussion started as why is this person flying this HCLT machine with their hands off and they are not dead. I answered with historical facts.

I know you flew the RAF, and I hate giving my opinion on someone else's design and responsibility, but I would not have sold a Gyroplane with a pod without a horizontal stabilizer, or I would have concerns about gusty winds and up or downdrafts.

I can answer for the Air Command, and I can tell you that a sever up or downdraft will not cause the machine to suddenly PPO. I agree that using a cardboard gyro and pencil will show you the affects of what should happen in a HCLT machine, but in the real world those effects do not translate into the disaster they want you to believe. A downdraft will not PPO an Air Command in the manner the fanatics are describing. The effect they describe is simply not great enough.

I always wanted to completely build my next gyro...and the SparrowHawk was exactly what I was wanting to go to.
After flying mine now for 170 plus hours....I can without a doubt say its the easiest machine I have ever flown. I actually had to deprogram some subtle reflexes that were now not necessary to fly. I am far from a superb pilot..but just an average one that flies by the seat of my pants. These machines talk to you and there just isnt much for me to do while flying.

I agree with you. This machine will fly more stable. It has some advantages over 25 year old designs. I am not saying, nor have I said that the HCLT machines are better than CLT or LCLT machines. On the contrary, I have said that they do have some advantages and are better for student pilots to learn to fly. I have no argument with this, but others here are making it an argument as if I didn't agree.

I said it here many, many times, and I'll say it again. There is no need for anyone to design and build a "classic" Gyroplane, nor is there any real advantage for a new person to Gyroplanes to buy a classic designed machine. How hard is that for some people to understand?

But that is not the issue to this tread. I am simply saying that the Air Command, the aircraft I can speak for, will not PPO in a sudden downdraft as the fanatics described. Gravity keeps the rotors loaded all the time, even while sinking rapidly.

I will let you aeronautical minds argue which is best....but if I am flying ignorantly blissful with my CLT, then whats wrong with that? I am willing to bet though that I am not flying in bliss...but in reality I am safer.

There is no argument, the CLT and LCLT machines are safer for new pilots to fly. I have never disagreed to that, also some here want to make it sound like I do.

No, you are not flying in bliss, you have a good flying machine that has advantages over anything you flew before.

Let me explain to you why I call some people here pencil pushers, and of course that would offed them. I'm a pencil pusher too, but I take pride in a deference between them and myself. It's called practical hands-on experience.

Every aircraft I built was designed by the numbers, mostly by me, but I always had aeronautical engineers ether on staff or independent verify my work. None of my designs, even to this day, have crashed due to a failure of a properly installed and maintained part, or crashed due to poor flying characteristics by a properly trained pilot, unless he was horsing around or was not trained to fly in the condition experienced at the time of the crash, in other words, exceeding his ability at his level of training.

I don't just talk about it, I do it, and I've done it time and time again;

Rotax 532 powered Bensen B8M Gyroplane

Prototype Air Command Gyroplane

Air Command 447 Commander

Air Command 503 Commander

Air Command 532 Commander

Air Command 582 Commander

Air Command 582 SXS Duel Seat Commander

Air Command 582 Duel Seat Tandem Commander

Air Command Commander Elite (includes all engines)

Air Command Commander Elite Jump-Takeoff Demonstrator

Mini-500 Single Place Helicopter

Mini-500 Talon Single-Place Helicopter (improved performance)

Voyager-500 Two-Place Helicopter

SkyCam-503 STOL UAV Gyroplane (Jump and POP versions)

Star-Lite FB-503A VTUAV two-Blade Helicopter

Star-Lite FB-503B VTUAV Heavy Lift Four-Blade Helicopter

These are the completed projects. I'm working on others.

Now, please, those of you that want to belittle me or that I called you pencil pushers, please, please stack your aircraft accomplishments here in the thread against mine.

Dennis....please...I dont want this to escalate into a pissing match....if it does I will just bow out as this forum has enough of this garbage as it is.

I agree with you, I try to give my opinion and years of hands-on experience here, and some people just have to start the insults and name calling. I don't want that, nor do I enjoy that. I just like to chat Gyroplanes. But I will not submissively agree with something I know is not correct. I find it appalling to be teaching new pilots to this sport incorrect information about the good flying characteristics of HCLT Gyroplanes through intimidation and incorrect information. Sure, teaching about the good flight characteristics of CLT and LCLT machines is great and necessary, but not at the expense of desecrating 25 year old aircraft that flew just fine, and serve us well even today.

I have always respected you and what you have done for the gyro community. I wanted an Air Command for years....and after flying one absolutlely loved it. Loved it so much so that I had to fly year round and I like heated cabins.
I have seen you in person clear back in 1985 at the Shelbyville, Il fly-in demonstrating the Air Command. You definately are a gifted pilot and a good promoter for this sport.
StanStan

That is what I am trying to preserve. Those days are being destroyed by the fanatics. I ask anyone that was a part of our sport back then to speak out and defend our machines that served us so well. Don't let people new to the sport that simply don't know the real story desecrate our old faithful companions. Keep the memories alive. They are the foundation which the future will stand on.

 

[chuter]

Dennis,

The only disagreement I have with
“A downdraft will not PPO an Air Command in the manner the fanatics are describing. The effect they describe is simply not great enough.”

is that just because it didn’t happen to you doesn’t mean it can’t happen.

People have suffered power-push-overs so they do happen.

The only thing open to debate (since we don’t have black boxes on gyros) is did PIO lead to the PPO, or did loss of rotor thrust (without PIO) cause it?

Maybe we can agree that it was one of those two causes?

My own suspicion is that it is probably a combination; flying in turbulence and getting a little behind with the stick, resulting in PIO plus a downdraft equals tumble.

Since we have no way of proving the cause beyond that point, we should attack the problem from both angles: get training, and design out the PPO.

I think that’s what you’re saying………..?

 

[bpearson]

When I became interested in gyros I found the old Norm gyro forum and started reading. It took me just a couple of hours to figure out that Chuck Beaty and Doug Riley are the ones I should pay attention to. Maybe that's just because I am a "pencil pusher" by nature, but I believe that anyone with half a brain can tell between experts and charlatans. I see many newbe's on this forum who "get it" very quickly and many "old timers" who don't seem to get it. The charlatans and the unsafe gyros are becoming marginalized very quickly. I see a trend towards safer gyros and I believe the gyro community will soon become more mainstream. Like with anything else, there will always be a fringe group sticking to the "old ways" - who cares.

Udi

Best post I've seen for ages. Spot on !

 

[Aussie_Paul]

I learned these survival techniques in the cockpit. I only later found out the "why" of it all, by pushing pencils -- and by dredging up half-remembered stuff from my freshman engineering courses a couple centuries ago. Until I dug into the topic, I thought all gyros flew this way and there was nothing anyone could do but learn the avoidance techniques and hope for the best.

It was quite an eye-opener for me the first time I flew my Dominator in some ratty air. To my surprise, I found that it held airspeed all by itself with no stick-floating and no need to reduce power at all. Damned if the thing didn't point into the up- and down-air like a dowser's rod, stick fixed. I had no clue that it would do that until I tried it for myself.

QUOTE]


Doug I too flew my AC s x s trainer the same way. It was a little more difficult instructing in it than flying it myself.

When I got my RAF and put the h/stabs on and found Norms forum I like many here argued that it was good enough. Compared to the AC and RAFs without stabs it was "wondeful". Then the pencil pushers, some who incidentaly have many gyro flight hours, kep t atr me with the physics.

I am just a lowly farm boy shade tree mechanic, BUT my old man taught me to try and understand what was going on with machinery. Everything the pencil pushers put forward as physics in a rational way had me keen to prove the theory. I did argure a lot, forcing people like Chuck B to persevere with
me.

Fortunately they did and I decided to build the next RAF kit as Hybrid. That got me realising the I was incorrect believing that a stab made enough difference to the very high thrust line to CoM offset ACs abd RAFs.

I then realised that gyros were just three axis aircraft with a rotating wing instead of a fixed wing and bear no resemblence at all to a helicopter other than it had rotors.

It was a little embarressing after my strong debates on Norms forum to say that I was wrong and now could see the light very clearly after actually conducting the tests with Hybrid.

I never thought that my AC was dangerous until I found out that it was highly unstable and that pilot skill was the only way to stay alive.

Dennis, I was Bert Floods, your Oz agent, test pilot and friend. The many ACs that I flight tested for Bert and his customers, and my own AC trainer were not stable, and their flight characteristics bore no resemblence at all to your version of how they flew. As I have always promoted, I now look at any gyro thinking, "will this gyro help my student or will this gyro hinder my students chances of survival."

I will not train people who do not have a stable gyroplane. We don't have to these days. The gyro industry is continueing to mature despite the Dennis' of this world who are stuck in the past.

Aussie Paul.

 

[Aussie_Paul]

When I became interested in gyros I found the old Norm gyro forum and started reading. It took me just a couple of hours to figure out that Chuck Beaty and Doug Riley are the ones I should pay attention to. Maybe that's just because I am a "pencil pusher" by nature, but I believe that anyone with half a brain can tell between experts and charlatans. I see many newbe's on this forum who "get it" very quickly and many "old timers" who don't seem to get it. The charlatans and the unsafe gyros are becoming marginalized very quickly. I see a trend towards safer gyros and I believe the gyro community will soon become more mainstream. Like with anything else, there will always be a fringe group sticking to the "old ways" - who cares.

Udi

So true Udi, a great short and to the point post.

Aussie Paul.

 

[JPHarrison]

Fetters has proven over and again that he has no aeronautical engineering qualifications, nor has ever offered to present any credible proof that his deathtraps underwent any professional engineering design, analysis, or testing. Other than his vituperative behaviour, unproven assertions regarding his qualifications, and "look at me, I've sold more deathtraps than anyone else on ths forum so you're not worth my time" statements, what proof has Fetters ever offered to support his claims?

Fetters' aircraft engineering qualifications boil down to "believe me, I really, really know what I'm doing, and my deathtraps really are safe and stable with benign behaviour at the edges of their performance envelopes, let alone right in the middle, so you should buy my product based on my word (would I misrepresent or conceal facts?) but remember, if you crash and suffer injury or death, it's not my fault that you took my word for it because my deathtrap is an experimental aircraft anyway and I have no responsibility to you or anyone else.

 

[dragonflyerthom]

When I was still a student pilot flying an AC447 gyro over the flat lands of Ohio the winds forcast said that the winds would not get over 5mph for that day and the next.

20 min after takeoff I found myself away from the airport and in 25mph winds gusting to 35.

An experinced pilot should know better then to trust the weather man or his engine.

.
If you can find a way to design out flaws in the weatherman more power to you man. Your apt to get quite rich.

Meanwhile, it is just common sense to design out flaws in airframes and designing out instablity is quite easy if you know the basic physics. Add a STAB!

.

Adding a Stab is just one of the steps to stabilizing a gyro in 2007. Training, training and competent training is the other method. There is so much information around pertaining to this, that the only way to miss it is to not be a member of this forum.

There are many ways to get around the barn. So the choice has boiled down to the builder. There seems to be a general decline in GA because of the expense of certified aircraft. This is causing a boom in the PPO, glider, and gyro market.. If we can get our $h.t together we can benefit from it. If not we will all become has-beens and the gyro community will slowly disappear.

This is our choice. Become a united community or the division will eat us alive. We must get our dissent under control for the benefit of the potential gyro pilot. Reduce or eliminate fatalities. Increase the number of hours to qualify for an add on or Sport Pilot. Give the Sport Pilot night flying privileges.
All to improve safety.

 

[Vance]

If I remember right Vance was flying near a mountain or big hill what ever you want to call it when this happened. Last year I went to a fly in with Larry Boyer at Mifflin County, the airport is nestled between to mountains and the winds were very mild as long as we stayed in the middle of the valley if you ventured close to the side it would kick the crap out of you. Mountain or uneven terrain flying is totally different then flat land and there are course available on what to avoid.

I don’t know why you would remember. I was flying near Buckeye, Arizona on a calm day at about 1,500 AGL with Steve in a SparrowHawk. We dropped like a rock and rotor rpm fell about 50 rpm. Steve cut the power and it was kind of a non-event.

I only bring it up to point out that no mater how careful I was I could not avoid a relatively sustained low G event.

Thank you, Vance

 

[barnstorm2]

Thom,

That is an excellent post.


Aussie Paul,

I too started out on the side of the apologists of unstable gyroplanes on norm's forum. Thanks to Chuck, Ron, Doug Smith and others I got a clue quick enough.

Training is imperative and required but you can't train out the laws of physics...


.

 

[Aussie_Paul]

Thom,

That is an excellent post.


Aussie Paul,

I too started out on the side of the apologists of unstable gyroplanes on norm's forum. Thanks to Chuck, Ron, Doug Smith and others I got a clue quick enough.

Training is imperative and required but you can't train out the laws of physics...


.

Absolutely.

Aussie Paul.

 

[StanFoster]

Dennis: I know I am not flying blissfully ignorant....I know I have a more stable machine. MY required inputs tell me it is so.

I taught myself to fly my Bensen back in 1985. I always undlerline that I dont recommend self teaching at all, but I went at it very slow and methodical and never had any surprises....except for MANY engine outs that ended up nothing more than nuisances to recover out of the patch I landed in.

I got out of gyros until 2002 when I bought my Air Command. It was non eventful the way I went about teaching myself the feel for this machine. I dont just firewall the throttle and hope everything goes right. I get the feel of the machine by a lot of time on the runway.

I went on to my RAF2000.....and even though I now had a seat for an instructor....I went about it the same slow methodical way....and no surprises.

Again....my SparrowHawk.....this time I did have a 30 minute flight with Terry Eiland a year earlier...but that was all and I just went out and got the feel of this machine.

The only damage I have done to any of my gyros is when my front spindle on my RAF broke off on takeoff with my dad in it. I kept the rotors off the runway as we ground to a halt. I had it back in the air with a new nosewheel strut in 3 hours.

Again....I dont condone self training.....but I had a lot of confidence in the way I go about it to take my new SparrowHawk and train myself in it as well.



Stan

 

[kc0iv]

Thom said:

Training, training and competent training is the other method.

I can't disagree with your concept. Finding competent training is the key. And that is where the newbie can have a problem.

If I may recall the beginning of my F/W training. I talked to a number of pilots and found what I understood was a good F/W instructor. So I hired this guy that was recommended. He had hours upon hours of training students plus he had been an instructor of over 20 years. What I didn't know and found out later very few of his students ever got their license. He had a number of crashes over the years.

I fired this guy when I called to cancel my lessons because the weather was bad I my mind. He said the weather was no problem so I said OK and we went flying. We had to get a special clearance just to leave the airport which I didn't known he had done. Well we hit icing so bad the aircraft could not maintain altitude. I was lucky we happen to be near another airport and with full power I was able to make a landing. I might add I had to make the landing since he couldn't see through the windshield.

Well I called my wife and had her pick me up at that airport. That was right after I fired the instructor.

I said all this to say how do you know what instructor to hire? I've read all the pros and cons of what people say about gyros. I read CLT isn't really isn't that important. With enough training anyone can fly anything. PPO really isn't that dangerous with enough training. Then on the other side of the fence people say just the opposite.

So who is right? They both can't be.

I'm just about ready to chuck the whole idea of flying a gyro and build a F/W where there seem to an idea of how an aircraft should be designed and built.

Sorry for the long post.


Leon
kc0iv