My Introduction to PIO and PPO (and survived)

[stevek]

About 20 years ago, I built and flew a benson B8V giro which I found
at the time to be over weight and/or underpowered. With my 14st on
board, I could get it airborne but it's climb rate was very marginal
(150 ft/ min max). However, it did fly and I managed to complete me
training on it with no problems - in fact it seamed an easy enough
machine to fly and turbulence and crosswind didn't effect it much at
all.

However, I stopped flying it and sold it to a lighter pilot within a
few months, as it lack of performance worried me.

Now, 20 years later (well, last summer) I thought it time to get
another one, so I bought a 'Cricket Mk4' which is like a benson with a
pod and a Rotax engine.

Boy, this was as far as I can remember, a different animal to fly.
OOdles of power. much lighter and needing a delicate touch on the
controls to get it down in one piece. Anyway I think I have got the
hang of flying it down the runway now!

A couple of weeks ago, one murky Saturday afternoon, I decided to do a
circuit. I took off ok, climbed to 500' down the runway and continued
a climbing turn to downwind. On rolling out of the turn I was
astonished to see the ASI at around the 70knots and dropping fast. I
could not perceive that I had put any control inputs in to cause this
and although there was no real horizon to see, my attitude did not
look or feel out of place. I left full throttle on and then watched as
the airspeed bottomed out at around 40knots and then climbed up
through 70knots . I then just closed the throttle and the machine came
back under control - it was then time to turn finals and land. The
point is, I never realized what was happening until it was nearly too
late.

You think I would have learned from this. I certainly did some
research on the 'net' about PIO and now I thought I understood what was
happening, I would recognize earlier and not get into such a situation
again.

That's a joke - last weekend I went to the airfield. Perfect day
5 knots down the runway and 10k vis. Time to try another circuit. And
guess what, this time, I have climbed up over the runway, turned
crosswind and i am lining myself to come out of the climbing turn
parallel to the runway. I am keeping one eye out on the clear
horizon as a pitch reference. I guess I must have let the nose drop a
little while rolling out of the turn and I was still on full throttle
with the airspeed rising.

I put a little back pressure on the stick and was about to reduce power
when the whole aircraft rotated forward.
I think both the fuselage and the rotor disk must have pitched forward
together as I felt no feedback through the controls. I was pointing
about 45 degrees nose down when the action of knocking off the power
completely stopped the forward pitching.

It had taken less than 1 second to get into this position. Fortunately, I
had just caught it intime and the rotors must have still had enough
inertia for me to use them as a flying surface. With the power off, the
gyro became a little ***** again and it ended with a good landing.

Now the point of all this is - I never expected the machine to bite so
hard and so fast with such little warning. I am surprised that more
people aren't killed in this situation - though I here a lot are and I
am lucky to be able to write this contribution.

Of cause, the Cricket has no horizontal stab. and a low body and c of
G compared to the thrust line.

A chap at the airfield has designed and fitted a horizontal stabilizor
to his cricket. He has applied to the PFA for a formal permit to test but with our regulations, no one wants to know. SO his machine is grounded and we
all have to perhaps take unnecessary risks flying.

Of course none of the designers or manufactures will admit that their
machines should be retrofitted with stabilizer I guess it would be
admitting a design weakness, and with it costing peoples lives, could
end up very messy in court.

Anyway, I feel I have got this off my chest a little - not sure where
I go from here - except keep the speed down and be ready to close the
throttle at any time!.

In addition, i felt that (at least in the UK) their are split opinions about whether Gyro should be configure for stable operation. Most of the long time expert pilots (including instructors) regard it as not a problem of the machines, but is something the student pilots should be aware of and learn to cope with.

This hasn't be explained to me in detail, nr the causes of PIO and PPO. I assumed that it was just a condition that would happen to capable Tyro's but not myself. Having spent most of my lifebeing involved in the control of high risk machine operating on the edge, I would not initiate PIO myself. I have had many years in high speed motorsport and have managed to conquer handling some 'on-the-edge' equipment.

SO it came to be a bit of a shock to find myself vulberable and to be honest, I was somewhat peeved to be accused for the blame to be put purely on my shoulders.

After a little research, I discoved that these were known problems, so I decided to try and help other coming from the same direction as myself. Being a webmaster for a number of commercial sites, I decided to launch an information only website to share my experiences and try to pull together as much material on gyro stability as possible, present in all in the one place, with he viewpoint of getting as many people to understand the problems and to try to have some influence with our authorities to be less hindering in allowing existing Gyro's to be retrofitted with essential stabilizing mods.

I am not trying to advetise my site to this forum's readers, I think you are all doing an excellent job with this site and I have found it mentally stimulating.

It would be cool if any of you have some copy on the subject on gyroplane stability that you would be prepared to share to visitors to my site,
http://www.gyroplanestability.com

It has only been in existance a few days and has no traffic yet, but I would welcome anything you can suggest I should incorporate to help with content.

Thanks for your time

[KenSandyEggo]

Yikes! I got scared just reading about your experiences.

[Aussie_Paul]

What a great story with an fine outcome that could have just as easily went the other way. Thanks for reporting that real life situation. How anyone could recomend an unstable machine for begginers, or anyone else simply amazes me. :eek: :eek: :eek:

PIO Pilot Induced Oscillation, is a bit of a misnomer. The inducement is usually a gust of bump that then causes the pilot to over correct.

I take it the Cricket that you bought is not the latest Cricket design that meets Section T?

Steve, thanks again.

Aussie Paul. :)

[jucie]

Glad to know you are ok, Steve. Thanks for sharing with us.

The transition from a weak engine to a strong one in unstable gyroplanes is a real danger. You are not the first to get a surprise like that, and the situation gets worse with modern, stronger and lighter engines. Those engines should be used only in stable gyros.

The english legal constraints for gyroplanes are unfortunate and misleading, in my humble opinion. I hope you guys can change that situation, so that you can try more stable configurations and fly safer.

[stevek]

What a great story with an fine outcome that could have just as easily went the other way. Thanks for reporting that real life situation. How anyone could recomend an unstable machine for begginers, or anyone else simply amazes me. :eek: :eek: :eek:

PIO Pilot Induced Oscillation, is a bit of a misnomer. The inducement is usually a gust of bump that then causes the pilot to over correct.

I take it the Cricket that you bought is not the latest Cricket design that meets Section T?

Steve, thanks again.

Aussie Paul. :)

No, it pre-dates section T. It's a Cricket Mk 4 replica, that was origonally sold by Everett Gyroplanes - built to the Cricket Mk 4 plans, so I am told.

I am not sure that there are any Section T complient Gyros available yet in the UK. The UK market is percieved to be small (I understand only about 68 machines have a current permit to fly) so it is an economic problem for a manufacturer to fund the work to demonstrate section T complience.

I know that the Cricket Mk 7 is going through this procedure at the moment and also Air command. I believe they are finding it hard going though. There is a push from owners at the moment to try to get approval to flight test a retrofit HS for a Cricket Mk 4 from the PFA. Although this may eventually happen, it's prooving hard work to get that approval.

You know what we Brits are like, always restricted by beurocracy!

One of the other problems overhere regarding Section T, is we don't have any suitable 2 seat machines that are suitable for training, except for one or two VPM's. most 2 seat training is carried out on RAF 2000's. Of course we cannot retrofit HS's to these, so they are hardly representative for the pilot who has to do 10hrss dual instruction in one, and then is expected to fly solo in a his own single seater - a different animal altogether.

It's a bit of a mess overhere.

We are short on instructors. with only one guy able to provide the training and test facilities for instructors, so this guy has a monopoly on it. He is the only one who can upgrade an existing instructor to have the facility to trin and test other instructor. So the whole training is in the hands of one person. Existing instructs seam to be unwilling to go through the procedure of being taught how to instruct by this one guy, as most have more experiencee instructing than he does!

It's all a bit of a mess. - I could go on about other problems in the UK scene but perhaps this is not the time or place. I have probable upset enough people already!

[Aussie_Paul]

..........upset the bastards. They need it!!!! :mad:

In 1997 I read the flight test report that got the Raf allowed inthe UK. The report said the machine was stable and suitable for teaching with!!!!!!!!! :eek:

The approved test pilots were the Raf agent, and his mate. :( Actually, I liked his mate who came over and helped with setting up my Raf. ;)

Not the best way to approve a design. :confused:

So keep at it Steve. :D

I thought that the new CLT Cricket was approved under section T?
Maybe not.

Aussie Paul.

[Heron]

. . .and they call themselves "authorities"!
Heron

[Doug Riley]

This situation is sad, unnecessary and in fact utterly ridiculous. A stable gyro exhibits no such deadly behavior. In a stable craft, a high power setting does not create any uncommanded nose-down pitching tendencies whatsoever. If anything, the nose rises a bit as you add power.

An unstable craft will exhibit odd pitch behavior in turns. FORWARD stick pressure is frequently needed to avoid slowing down in turns. This is the opposite of a stable response. When rolling back to level, this forward pressure can result in a dive (or dip of the nose at any rate) -- which may explain the first incident.

No such nonsense happens in a stable craft. BACK pressure is required in a turn (a stable response, much like a FW plane).

[Chuck Irby]

Steve, That sounded quite scary. Glad you're still with us.

Doug, well stated.

[StanFoster]

Doug: I second that with Chuck...well stated.

My RAF most definately has to have more back stick in a turn. I did Greg Gremmingers stability tests and so far...everything is reacting the way it is supposed to.

I of course have the stab and it is doing a wonderful job of keeping the keel at around 2 degrees nose down. I posted sometime back pictures of the warp drive protractor as I flew at 55..65..75..and 85. No measurable or felt difference in nose down attitude of the keel.

Stan

[gyrogreg]

The attitude of the UK CAA is unbelievable. We certainly know how to make gyros stable and safe now. To deny pilots the ability to make their gyro safe to fly is criminal. Gyro pilots in the UK ought to be up in arms. Has anyone tried to familiarize the CAA authorities in at least the static stability issues with gyros - these issues are not difficult to understand. I hope we will soon have the USA LSA gyroplane ASTM Design and Performance standard approved - to make it available to those backward authorities. This is a dangerous situation for a whole country, and should be fixed - NOW!m There are no excuses for denying someone the right to install a HS or reliable engine on any aircraft!!!!!

- Greg Gremminger

[stevek]

The attitude of the UK CAA is unbelievable. We certainly know how to make gyros stable and safe now. To deny pilots the ability to make their gyro safe to fly is criminal. Gyro pilots in the UK ought to be up in arms. Has anyone tried to familiarize the CAA authorities in at least the static stability issues with gyros - these issues are not difficult to understand. I hope we will soon have the USA LSA gyroplane ASTM Design and Performance standard approved - to make it available to those backward authorities. This is a dangerous situation for a whole country, and should be fixed - NOW!m There are no excuses for denying someone the right to install a HS or reliable engine on any aircraft!!!!!

- Greg Gremminger

Greg

I must thank you for your well informed feedback to this debate. I quess someone does need to put some pressure on the CAA to take a close look at the UK problems and not too much is being done at the moment, I guess I shall have to take on that mantle!

Of course it could all go wrong and if pressed too hard, they may take the view that all Gyros should be banned.

With your practicle tests to measure static stability, I am sure that most existing Gyro's could be retrofitted with a propably designed HS to provide the required downthrust to balance the high prop line machines.

As I interpet it, the HS in the prop slipstream would need to be sized, positioned and have an rigged angle of incedence (with a suitable airofoil section) to counter the couple created by the engine thrust (proportional to the propwash airspeed^2). As some gyros have an inclined prop thrust line, this would have to be taken into account when setting the AOI of the HS.

A section or seperate HS positioned in the free air is also needed to produce the dowforce required to combat any nose up moments created by the fuselarge drag ( proportional to the airspeed^2). Also the section in the propwash will also be effected by the free airspeed and the different AOI this component presents itself.

Have I got this right?

The HS's Ihave seen in the UK are all just a flat plate bolted on to the keeltube and while they do have a positive effect on dampening dynamic instability, they show a complete misunderstanding of the more complex picture.

I would image when the CAA see these mods being put forward, they must think the 'designers' are out of the arc, and can't take them too seriously.

We need someone to design aproper solution, with the aim of producing the static stability as demonstated in your 3 flight tests.

I am sure if all Gyros were retrfitted to these standards, not only would the novice pilot have an easier time, the instructors could then have a more standard procedure for instruction and pilot could move between machines a lot easier if they have consistant flight characteristics. :rolleyes:

Sorry about the grammer and spelling, It's 2.00am and I must get some kip.

Good Night all

[gyrogreg]

Steve,

You do appear to have a very good handle on the static stability issue. When you get static stability right, the HS is most likely to also provide at least adequate dynamic stability. You sound like the one to pick up the ball with the CAA. Good luck, and feel free to use any of my material to spread the word. Watch for any posts on when the Gyroplane ASTM standard is approved and available - but you have got the gist of the stability part with the three static stability tests.

Thanks, Greg

[birdy]

That's odd,my RAF requires back stick during a turn too!!!

[Udi]

I wish you all the best, Steve, working with the UK authorities. May the Force be with you. I have some comments, though, with regard to your analysis of the function of the stab.

As I interpet it, the HS in the prop slipstream would need to be sized, positioned and have an rigged angle of incedence (with a suitable airofoil section) to counter the couple created by the engine thrust (proportional to the propwash airspeed^2). As some gyros have an inclined prop thrust line, this would have to be taken into account when setting the AOI of the HS.

Although the design you have described above is the most desirable design, it is not mandatory, in my opinion, for positive stability. A keel-mounted stab goes a long way towards making a gyro stable, even if the high thrust line moment is not completely cancelled by the stab. I can go into some explanations why this is so, but Stan Foster's description of his RAF (above) is a good testimony to this fact. In my opinion, a high thrust line gyroplane can be made to pass Greg’s static stability tests, even when the sum of all the moments about the CG is nose-down.

One advantage of actually canceling the high thrust moment is making the gyro PPO-proof. A gyroplane in which the high thrust moment is completely cancelled by an effective stab cannot PPO. A keel-mounted stab may make a standard RAF much more stable, but not PPO proof. We have to separate between these two issues - stability, and PPO. Separate, although related, issues.

A section or seperate HS positioned in the free air is also needed to produce the dowforce required to combat any nose up moments created by the fuselarge drag ( proportional to the airspeed^2). Also the section in the propwash will also be effected by the free airspeed and the different AOI this component presents itself.

Fuselage drag is usually producing a nose-down moment. Even so, a stab that is immersed in the prop wash would correct for this better than a stab in the "free air". The only time this is not so is when the prop wash is not there (e.g. due to engine idling or off), and the stab is located in the wake of the fuselage.


The HS's Ihave seen in the UK are all just a flat plate bolted on to the keeltube and while they do have a positive effect on dampening dynamic instability, they show a complete misunderstanding of the more complex picture.

A keel-mounted flat plate stab may be totally adequate if other factor, such as a high thrust line offset, are not too out of balance. Many fixed wing airplanes are flying just fine with a flat plate HS. Also, one of the most stable gyroplanes, the Little Wing, is using a flat plate for a HS.

I think that your job with the authorities will be easier if you keep the requirements simple. There are good, better and best for anything.

Good - I think that any effective stab is better than no-stab. I say "effective", because a rock guard is not an effective stab.

Better - a stab that is also canceling a high thrust line offset is even better.

Best - a centerline thrust (CLT) design with an effective stab is best. This is the most efficient design.

Just one more clarification - when I say, "centerline thrust" I don't mean that the thrust has to be exactly in line with the CG. This can never exist in reality. For me, a CLT machine is one in which the thrust line is within +- 2 inch of the CG.

Udi

[scott heger]

Steve, maybe I missed something here, but it seems to me you described a" P.P.O ", or (a almost in your case) power push over, more than a P.I.O.. Many a gyro pilot don't get a chance to describe it, because they end up dead. It sounds like you are flying your machine at the tip of it's flight envelope, and I would be VERY careful!!!!!

I am not the lecturing type, but your near upset is disturbing; You may not be so fast on the throttle next time. Please consider reevaluating you machine, its flight capabilities, the weather/wind you fly in, and your skill level before proceeding alot farther. A big gust of wind, also known as a G.I.O, (gust induced oscillation)may cause a situation that you can't handle either.

Scott Heger, Laguna Niguel, Ca SportCopter N86SH

[jucie]

I bet the english authorities know these stability issues very well. Imagine how many comments, e-mails and communications of every kind those guys had received by now. They understand that issues pretty well. It is not missing knowledge that avoids further progress. There is some hidden interest, for sure.

May I speculate a little? Maybe the intent is to protect the market for the english manufacturers and their gyros. If the authorities change the rules, then people will seek for alternatives at unknown sources, possibly outside England. Maybe they are waiting for new, stable english gyro projects to be ready for mass production. Only after that they will change the rules.

When logic doesn't explain, malice does.

[Chuck Irby]

Scott Heger, well put. I concur.

[stevek]

Steve, maybe I missed something here, but it seems to me you described a" P.P.O ", or (a almost in your case) power push over, more than a P.I.O.. Many a gyro pilot don't get a chance to describe it, because they end up dead. It sounds like you are flying your machine at the tip of it's flight envelope, and I would be VERY careful!!!!!

I am not the lecturing type, but your near upset is disturbing; You may not be so fast on the throttle next time. Please consider reevaluating you machine, its flight capabilities, the weather/wind you fly in, and your skill level before proceeding alot farther. A big gust of wind, also known as a G.I.O, (gust induced oscillation)may cause a situation that you can't handle either.

Scott Heger, Laguna Niguel, Ca SportCopter N86SH


Scott

Thanks for your comments. What you say is very much what my instructor has tried to drum in to me!

I admit that my flying experience in the past 20 years and flying at a height of greater than 40 feet is limited to less than 1 hour. So yes, I am inexperienced. I also have agree that the basic fault was mine for allowing the speed to build up too high.

At some point, all training Gyro pilots must have the same level of experience as me. what I didn't realize that the machine would become oversensitive and /or unstable at a speed lower than the VNE. Even now, I cannot get an answer to my question 'what should I limit the speed too?'

I am told to fly it as a comfortable speed that I can keep it under control.

So to find the upper limits of the envelope, I have to be able to recognise when this has been exceeded, before I reach it. In both occasions, I didn't recognise the problems until it was nearly too late.

On both occasions, in was reliably observed that the Gyro had started to porpoise and on the second occasion, this lead into the PPO situation.

So what really concerns me is that I could get myself into this situation, twice without recognising it's onset - not so much that the Gyro will behave in this way. I don't believe it is just my lack of experience or lack of flying skills that are the problem - everyone has to start from somewhere. Nor do I believe that my Gyro is inherantly dangerous. But i wish someone could define a flight envelope I could follow to ensure consistant and predictable handling.

When i started this training cycle last year, I was surprised to see that at Henstridge, there were such a large percentage of the student pilots taxying up and down the runway doing nosewheel balancing, but never actually getting beyond that point. Having joined in the social chat, it appeared to me that many had proceeded beyond the point they were at, had a fright in some way and had built up a general air of fear of the machines leaving the ground.

With so many of the Gyro's in use being variations of the old Bensen designs and all having some differences, I am sure they probably have different unwanted handling traits.

On my Cricket, I was surprised at the various pitch changes that occur with different power setting and wind gusts - on take off and especially on landing and botched landings.

I am convinced that this is making a novices learning more difficult as there are other things to do that trying to compensate for a machine's mind of its own when trying to fly and land the Gyro.

Is this why these guy's are still spending their weekends nosewheel balancing? I can't believe they are all wary for no reason.

Even on of our more experienced flyers when flying a RAF2000 (no HS) admits that on an approach, he likes to get the machine lined up to the runway, with the throttle at a fixed settiing and the airspeed correct - at least 200' QFE so he dosn't have to make any power changes before actually landing. He doesn't want the additional complications of the secondary effects of a power change to add an additional workload at that time.

That's enough for now and Scott, thanks for your input - I shall be more careful next time!.

Steve Kirkby

PS - John Kitchin - Have I spelt Bensen right this time?

[bpearson]

First post so hope this works ! I feel I should defend the Cricket's safety record. The design is over 35 years old and in the thousands of hours flight time only one fatality. This occured to a pilot who's own gyro was a heavy VW powered benson. He was relatively inexperienced and proceeded to fly the Cricket beyond his skill level. I too learned to fly on a Rotax Cricket and never encountered PIO or any other nasties. Should state at this time that I am a very inexperienced novice trainee. However, I never went anywhere near 70 knots on my first circuit or even after leaving it. When I later did experiment with higher airspeeds it became a much different animal. I found 50 knots to be a comfortable speed. One thing that always concerned me was would I know if I was in PIO. Other Cricket trainees who had experienced PIO told me I certainly would. They also said it had occured after letting the airspeed rise. Now I am not saying the Cricket can't be improved on but it most certainly is not an Air Command (pre mods). I am not qualified to offer any advice Steve but my guess would be keep that airspeed nailed. One more thing. I learnt on a VPM, but before single seat work I flew the gyroglider a few times. I think this was a real help in getting to grips with the light touch a single seater requires. These seem not to be used these days.

Brian

[automan1223]

Thanks so much stevek for sharing that with us. As a student pilot with much to learn, it is very serious that you start with a safe and stable machine. Life it to short to become a stat. There is just no real reason other than pure lazyness that you would need to fly a dangerous machine that needed attention every micro second of your flight.

Jonathan

[PW_Plack]

Steve K,

You'll find the debate confusing, with seemingly qualified people arguing on both sides of the PPO question, until you understand their only real item of disagreement:

Can PPO happen spontaneously, a sudden, deadly rotation from straight-and-level flight caused by a gust or other turbulence, or is it only the final result of a series of oscillations which could have been caught by a pilot with proper training? Some will argue training is the best solution, others will say redesign the machine. My novice conclusion is, do both.

IMHO, this is the only argument left on the subject. I can find no one (outside the British government) who doesn't acknowledge that having the thrustline aligned closely with vertical center-of-mass doesn't create a safer machine. (Well, allright, outside the British government and one major Canadian kitmaker.)

[rehler]

Steve,

You asked what speed.

I suggest that when you learn to fly that you concentrate on controlling your speed with your cyclic stick and not your throttle and that you use your throttle to gain or loose altitude and not your cyclic stick. Throttle for altitude, Stick for speed.

Then, using your cyclic stick, maintain 50 mph for take off, climb, cruise, approach and landing. Keep it at the same speed during all phases of flight (until just before flare and touch down).

Then after you get used to flying the gyro (at least 10 hours) you can increase your speed.

[stevek]

Steve,

You asked what speed.

I suggest that when you learn to fly that you concentrate on controlling your speed with your cyclic stick and not your throttle and that you use your throttle to gain or loose altitude and not your cyclic stick. Throttle for altitude, Stick for speed.

Then, using your cyclic stick, maintain 50 mph for take off, climb, cruise, approach and landing. Keep it at the same speed during all phases of flight (until just before flare and touch down).

Then after you get used to flying the gyro (at least 10 hours) you can increase your speed.

Sounds like flying a FW. If my gyro is power stable then yes, increasing power should make the machine climb at the same speed and retrimming the rotor pitch, the gyro should stabilize at a new airspeed.

I am not sure yet whether my gyro has that stability in those two variable changes but it's the next thing I am going to find out - trying Gregg's 3 flight tests for the different static stability modes. If it doesnt, then I am in for a harder time I guess - until We can make the CAA see sense and allow tested mods to bring the characteristics back into a stable regime.

meanwhile, I will take your advice and stick to 50 knots at all time. Thanks for your advice. It's good to be able to have a sensible conversation with this group - I don't feel I can talk open mindedly in the UK. Too many toes to tread on and I do not want be be alienated by the small community I have to (and enjoy) mix with.

I am beginning to see that perhaps I am taking a cavelier attitude and must look like a prat who f**ked up and is looking to blame the tools.

I reackon that all Gyros should have a flight manual that shows the audited results of a set of flight tests along the lines that Gregg Gremmiger and his group are formulating. This includes the existing machines that pre-date section T. The flight manual should be made available when the machine changes ownership, so the new owner can make a better informed decision when purchasing it.

To work alongside this concept, the CAA/PFA , should assist in the design and authorization to preform whatever mods are required to help these old machines improve their staility ratings.

This would apply a positve incentive for the current owner to improve his machine -if not for his own benefit, but make it more ssaleable when it is sold on. The buyer will also also have a good idea what he is buying.

I could then see a dramatic imporvement in the whole gyroplane scene in the UK, with fewer accidents and pilots having fewer problems moving between types, as they should share more similar flying characteristics.

Have anyone come up with any benefits for an unstable Gyro?. I know they are plenty of examples in other forms of transport, often due to fast control response requirements on sports/racing/military aircraft. But i am not sure if they are relavent to the Gyro


Steve Kirkby

[rehler]

Steve,

The "stick for speed and throttle for altitude" is the same for all gyros, regardless of how power stable they are. That is how you should fly a gyro.

In general, you should never use throttle for speed or the stick for altitude.

It is the same as fixed wings only in "slow flight". Basically, gyros are always in slow flight.

[scott heger]

Steve, I am glad your are considering all the possible problems as well as solutions. You said that many students you see just taxi back and forth in a (assuming two wheel) balance. A mistake at that point in training is only going to cost a set of rotor blades, and maybe a scar or two, not your life. As you found out once you are airborne, everything (wrong) can happen very quickly. In reality, it isnt happening all that fast, but your mind is not processing all that is happening, and reacting quickly enough. That comes with many hours solo piloting. The first few hours of solo flight in a gyro, I like most, had some poor landings. I look back at the mistakes now, just shaking my head why I did not make the correct inputs quicker.

I did my training in a dual very stable gyro. I also fly a very stable high performance gyro. That doesn't mean I have not been in one that was unstable, and it can be a unpleasant ride. I believe 1 hour of airborne dual is worth many hours of ground/internet/ best friends advice/etc kind of instruction. Balancing on the mains can be done with ground assistance. However once airborne a good instructor can help you recognize a flight problems before they get out of hand. I agree with Ken, that speed management should be a top priority, 50-55 MPH max till you get some hours built up. Don't take off if the wind exceeds what ever your instructor states. Our NTSB (goverment crash records) is full of high flight time FW pilots that have gotten into a gyro and fatally crashed within the first few hours (or sometimes seconds) because they think they are easy to fly. Well they are easy, it just takes practice and patience.

Scott Heger, Laguna Niguel, Ca SportCopter N86SH

[bpearson]

In my recent post I defended the Cricket gyro's safety record and flight characteristics. I did this partly because I believe it is a safe machine but also because of the following...... Here in the UK we do not have the freedom to fly what we like. The authorities will not allow us to fly proven machines let alone develop our own. They were bitten hard by the Air Command accidents. A UK enthusiast recently suggested all existing UK gyros should meet our section T requirements. The CAA would love that. No gyros would fly again....... problem solved ! If enough people say Crickets, Bensons are deathtraps they will be grounded. Then our gyro safety record would be the envy of the world.
Brian

[scott heger]

Brian, if the goverment lowered the top speed limit in cars to 40 kph, your Country would have the safest accident rate in the world also. Sometimes regulations get silly. You have to remember, in the the U.S., the FAA is not really concerned for the pilot, but for protecting the public at large. If we had a bunch of accidents of gyros hitting persons on the ground or damaging others property, they would come down on us hard. The reality is I don't know of ANY accident in the past 20 years where a non passenger or pilot was injured by a FLYING gyro in the U.S. It may have happened, but it hardly any large public safety threat.

Many gyros are flown out of rural airports, and alot of gyro pilots don't have licenses to fly them. The culture in our Country is not to turn fellow pilots in for rule infractions. The FAA is way to busy to normally mess with some local gyro flyer unless he is making a hazard of himself. I fly into many Los Angeles area congested airports in both my gyro and helicopters. I have yet to be ramped checked as a pilot. Last year I actually parked next to a FAA field office, and four of the officals came out looked at the gyro, and never asked for any paperwork, even though two of the observers were inspectors. We do enjoy much more freedom here to design, modify(and improve) our machines without more than a log entry in the airframe book. Gyros in the U.S. are just a very small fringe aviation group. The more we can all do to present a good image of the sport, and disspell old myths, hopefully things will change for the better, and more people will get interested in the sport.

Scott Heger, Laguna Niguel, Ca SportCopter N86SH

[bpearson]

Scott. I sometimes despair at the way our governing bodies view sport aviation in the UK. You are totally right. Example : We build our outdated gyro. We are not allowed to make it safer (someone fitted H/S to Cricket for export and test pilot said it was amazing........ two years on, still waiting to be cleared). We now need a trailer. No regulations here to speak off. Yet we tow our machine around, inches away from people knowing that if it were to fail we could wipe out a bus queue or derail a train... actually happened here three years ago.
We can build one off design cars, then after a reasonable inspection we can tear up the road alongside all the mass produced cars that cost millions to develop. I envy you and other countries that allow their people the right and freedom to decide for themselves what risks they can take.
I have argued for many years we need to recognise in law the disclaimer. But as lawyers run this country I doubt they would ever do themselves out of work !

Brian

[mceagle]

Steve,
It is good that you are still around to tell us the story.
It sounds like a typical case of what is popularly called PIO to me.
PIO starts with the pilot over correcting a perceived attitude defect in the Gyro and if the pilots response harmonises with the pendulum frequency of the gyro, full blown PIO developes. If not stopped, the Gyro finally tumbles forward due to lack of corrective control movement, drag under or PPO.
A gyro student pilot should never be allowed to fly the pattern until he nas nailed the gyro "attitude" under all conditions likely to be encountered in normal flight.

[Doug Riley]

Steve K., the problem is PRECISELY that your gyro IS inherently dangerous. It's not your fault. You're apparently caught in a strange political bind, but the laws of physics don't care about politics. Mother Nature certainly will NOT give you a break just because your machine's dangerous configuration is the result of politics.

To repeat, a pitch-stable gyro will not behave as you describe, even if the machine IS somewhat mishandled (as you also describe). A pitch-stable machine's nose gradually rises as you go faster, requiring more and more forward stick pressure to avoid climbing. A pitch-stable machine does not become twitchy or unduly sensitive as you speed up -- quite to the contrary, it feels "stiffer" and more solid as you add speed.

To be sure, there are specific techniques for handling unstable aircraft. So many gyro models were unstable in years past that these techniques came to be thought of as "standard gyro" techniques, which they are not. Among the supposedly "standard gyro" techniques that are really "standard unstable aircraft" techniques are (1) be ready to close the throttle at the first hint of PIO or turbulence (2) use short "jabs" rather than steady pressures when manipulating the stick (4) make liberal use of "reverse jabs" to stop rotations of the fuselage even before you're achieved the response you wanted (4) be very watchful for airspeed loss in turns, and be ready to use forward stick to prevent it (5) always adjust power before adjusting stick pressure ("power before attitude").

If you cannot legally add an effective horizontal stabilizer to your gyro and adjust the CG's vertical position for substantially centerline thrust, then all of these techniques will apply.

A stable gyro flies much like a fixed-wing plane, except for the effects of its lower lift-to-drag ratio. The special techniques applicable to unstable aircraft do not apply to stable ones.

Having flown unstable gyros for years and having switched to stable ones, I'm not sure I'd fly gyros at all if the government forced me to fly unstable configurations.

[Chuck Irby]

Doug, you've done it again. Very well stated.

[jucie]

Steve, here in Brazil he don't have those constraints as you, english guys, but because of tradition, all our gyros are old fashioned, unstable configurations. That is unfortunate (hopefully we can change that soon); but my fellow pilots are flying for decades using those technics Doug just mentioned above. They don't even know things could be different.

I'm not sure I'd fly gyros at all if the government forced me to fly unstable configurations.

I would. Excuse me, Doug, that is only my personal choice. It has to do with a dream to fly. Some things are stronger than logics. :o

[stevek]

Doug,

As i thought, I am being hit by both sides of the argument. Thanks for your suport and practical advice, It's surely appreciated. I wish I had found this forum earlier.

I shall be trying myself to go through the procedure to get a mod approved from the PFA/CAA. Perhaps if enough pilots in the UK were to do this, the message may get across that there is a requirement by UK pilots for improved safety for the lower hours pilots.

If I run across any genuine resistance for this from the authorites, I will post me progress on this forum.

and regarding the Cricket's safety record - It's no worse than any other non-stabilized Gyro and in all other respects, is a fine little flying machine. I have myself never gone to the extreme of saying they should be banned, but I do fear that if too vigerous a point is made to the authorities, that is exactly what could happen. So a little diplomacy is required (not generally my forte!).

My ideal scenario would be for the authorities to assist in allowing non factory mods to be made on the basis of safety grounds, and reducing the opportunity for pilot errors (as that seems to be the main reported cause of any accident that isn't attibuted to a structural failure)

With section T , I would hope that all new Gyro's will now fly in a stable and predictable fashion like fixed wing aircraft do and not have any unpredictable traits.

This still leaves the existing Gyro base. I would like to see formal test flight results relating to staic and dynamic stability being made available to the purchaser, if a Gyro changes hands. Together, with a simpler procedure fo mods to be made and perhaps the publication of approved mods as they become available, would over time, sort out the existing stock. At least, new owners would have the details of any stability deficiencies so it would be an incentive for the owner to get his machine up to spec before passing the problems on to someone else.

Blanket banning would only push the movement more underground than it is now.

Steve Kirkby

[gyroman]

Steve maybe this will help in your report, its a past thread describing an RAF fatality in the UK, it contains the link to a CAA report decribing the accident. The CAA inspector did a pretty good job of investigating the accident and states the characteristics of the gyroplane and recommends the use of a HS.

UK RAF Fatality thread (http://www.rotaryforum.com/forum/showthread.php?t=1118&highlight=fatality)

[bpearson]

In reply to the above ascertion by Doug. I do not agree at all. The Cricket has a small prop, like original Bensons. It is not a high performance machine. Hundreds have flown over many years with no problems. I susect that the thrust line is not a million miles out.
Please don't scare our potential gyro pilots too much. The Air Command achieved that !

Brian

[Chuck Irby]

Brian, many unstable machines have been flown for many years and many will continue to be flown for many years to come. Many people have died that would not have had they been flying stable machines. I have flown both unstable and stable machines. I have a choice as to which one I fly. I will continue to fly stable machines.

[Dean_Dolph]

Brian, are you saying that Bensen's are stable machines! Long before there were Air Commands, Bensen's were killing people. The intent isn't to scare potential gyro pilots, it is about educating them so they can stay alive and enjoy gyro flying with out any unintended adrenalin rush.

Also why are you so sure that the Cricket thrust line isn't way out of whack. It has been demonstrated, by the GyroBee for instance, that you can not eyeball the thrust line/vetical Cg relationship. If you want to sustantiate your claim then I would suggest you find a Cricket and go thru the vertical Cg determination procedure. I'm sure someone here can supply it. Even then it is very possible that any two machines will check out different unless they are constructed exactly alike.

[Doug Riley]

The Bensen had an awful safety record. I joined PRA in mid-1969 and have been reading PPO and PIO accident reports ever since, starting with the first issue I received. It was not unusual to have a couple such accident reports in a single issue. Most Bensens had a thrustline enough above the CG to allow PPO after a few cycles of porpoising, thanks to the low-mounted metal gas tank, heavy wheels, short mast and light blades. The fact that the prop was only four feet long was not enough in itself to make them stable.

Yes, the Air Command made a bad situation worse. My comments about flying unstable gyros come from a number of years of owning and flying a stock 1985 Air Command, with inverted engine and no HS. The CG was a good 5" below the thrustline, even without the pod, brakes and auxiliary tanks. I'm still alive, thank you, but there were a few flights in turbulence where that outcome was far from assured. The simple addition of an HS, even when the low seat and inverted engine were retained, made an astonishing improvement in this craft's handling.

The flight behavior reported at the beginning of this thread is characteristic ONLY of gyros that are statically unstable in pitch. A fuselage pod can contribute to instability in a craft that's otherwise benign... especially at higher speeds. If the aircraft is to have a pod, its configuration must assure stability with the pod mounted.

I have every intention of scaring the heck out of gyro pilots about this issue. Entirely too many people think that stability is some low-priority option on an aircraft (like metalflake paint, perhaps). There is no excuse for flying Dark Ages aircraft when we know better.

[Heron]

I came in the forum about 3/4 years ago and did not know anything, I wasn't scared of the subject and did my home work looking to fly on recommended machines, so far so good . . .
Warnings are good! The police every now and than have shows with grusome pictures to wake people up for the consequences. It does not scare people out of driving!
When a machine sucks . . .it sucks! (Just like the PRA . . .heheheh) The Devil . . .it was The Devil . . . .:D
Heron

[Chuck Irby]

Heron, I don't care what every body else says about you. I think you're alright. :D

[Heron]

That I will take as a compliment . . .I am getting old and grumpy and frustrated and sarcastic and . . . .you add the rest!
But I still love to provoke short circuits . . .
Heron

[StanFoster]

Heron: When I first started on this forum..I knew absolutely nothing....today...I know twice as much. :D

Stan

[Hognose]

The Bensen had an awful safety record. <snip> Most Bensens had a thrustline enough above the CG.

Doug, I won't argue the Bensen's safety record. The NTSB now goes back to 1962 online (for years it only went back to March, 1983, which was when they started putting the data in their mainframe) and there are just many large numbers of Bensen prangs, a lot of them fatals.

Looking at those accidents, the principal causes are (1) poor judgment or ADM, still #1 today, and (2) poor training. Most of the Bensen-era gyronauts were self-taught. And everybody who survived loved the sport :( .

Yes, you can build a Bensen with a dangerously offset thrustline, and no, the Bensen design did not include an Hstab. (The rock guard is not a stab, it's a rock guard). But if a Bensen was built according to plans and the pilot was FAA standard 170 lbs, the thrustline ran right through the CG. This is deliberate and in fact is referenced by a callout on the plans.

Also working in Bensen's favour was the low thrust of the direct-drive Mac. The specs said what they said, but a Mac probably made about 40 HP in the real, physical world.

When Air Command put a more powerful (real world) motor on, with a gearbox, it needed a longer prop to max thrust, and DF ddidn't understand that there were consequences when he raised the engine for prop clearance. Instead of 40 HP through an inefficient prop on centreline (or max a couple of inches higher) you had 65 HP through an optimized prop and thrustline maybe seven inches higher than centre of mass.

The amazing thing is not that people died in those early Air Commands, but that anybody who flew them lived.

cheers

-=K=-

[Udi]

Looking at those accidents, the principal causes are (1) poor judgment or ADM, still #1 today, and (2) poor training.

The NTSB normally and routinely blames PIO/PPO accidents on pilot error. They never blame the machine. I guess that is correct to some extent; after all, it was a pilot error to fly that machine in the first place...

Udi-

[Hognose]

Udi,

I agree with you in ref to the more recent accidents, but look at those Bensen prangs. A lot of self-taught guys doing real dumb stuff. Which can happen if you are self taught and no one says, say, "don't try to show off, it is dumb stuff."

In the NTSB site, I pulled up the first ten years' Bensen accidents. From 1/1/62 to 12/31/71 there are 119 accidents in the file that come up on the Bensen search. Looking throug the fatals, the first few did not come up PPO but then they started showing up. Most of them seem to be deliberately initiated by the pilots. ("Was observed to zoom to 500 feet and then push over.") I only saw one PIO and that was in a guy with time only in non-powered gyros. There were also quite a few material failure accidents, result of deviating from plans. There is not much information in these early records and you have to try and tease meaning out of the bureaucrats' telegrapic prose.

It is certainly possible that an experienced-enough pilot , one who has survived his initial hours (unlike these Bensen drivers, most of whom were gyro novices despite some of them having thousands of hours in other cats/classes), has inoculated himself against PIO by experience in type. PPO is a different matter. You could be minding your own business, and a gust-generated zero-G event can remove your rotor thrust vector from the balance equation. If you have a high thrustline with only the RTV as balance (which perfectly described the pre-Larry Neal Air commands, and the standard RAF 2000), Jesus Christ Himself won't stop you from going over. A good aftermarket horizontal stab might, but that depends on airspeed and power setting. At low airspeed and high power setting the thrust might overpower the stab. And over you go. Very rarely a pilot survives such an event -- a statistical outlier, not to be relied upon.

I do think the PPO initiated by pilot error is more common than one initiated by gust. But to have a machine that is prone to a fatal tumble, when that is easily correctable, is madness.

It's sad to see the PFA in Britain so stodgily unable to react to this, when some of the best gyro research was conducted by the University of Glasgow under the auspices of CAA, from whom PFA derive their authority. CAA sponsored that research in the interests of safety, you would think that PFA would learn from the research for the same damn reason. Some people have vested interests and try to make it seem like it is a clash over unimportant opinions, when we know it is not. Some of that is the product of US and UK schooling which has become rather weak in maths and science, and determined to be non-judgmental about anything.

Well, here in this forum we can still be judgmental about "stupid."

Another problem peculiar to Britain is the intransigent attitude of Wing Commander Wallis towards stability -- it sets him off like one of those mock letters to the producers on Monty Python. He is "Mr Gyro" over there and his words are taken very seriously.

cheers

-=K=-

[Doug Riley]

Hognose, you've done us proud. Well said (including the cogent social commentary).

I think Bensen was simply lying when he called out VCG location on the prop thrustline. (He did lie, now and then.) It's probably true of a Brock KB-2, but not a stock B-8M with all the heavy items at axle height, short mast and light blades.

[birdy]

Kevin,
I'm not trying to be a smarta..,but why don't you like Ken???
Would you say his machine is dangerous???[the one he constantly flys hands and feet off]

[Doug Riley]

The hands-off thing is, in a sense, a parlor trick. Just about any gyro, whether it's stable or not in the usual ways that aircraft are evaluated, can be flown hands-off in smooth air at a certain airspeed and power setting if it has an offset gimbal head and the right trim spring.

I used to have a little aerial photo business. I sometimes used my early-model Air Command as the photo ship. With the springs a little tight and the throttle just above cruise power, I could make 35 mph passes at the target while manually focussing, taking light readings and squeezing off a whole series of shots... all hands-off.

This worked if the air wasn't too rough. It didn't work well at all in turbulence. As you get into periodic low G's in a high-thrustline machine, the nose starts to move in the wrong direction. These pitching movements of the airframe can mislead the gimbal head by changing the spring tension... so that, even hands-off, the head "sees" a rotor-forward command when the nose dips. That's a classic unstable reaction.

Cmdr. Wallace's machines are probably closer to CLT than an early Air Command, so they would tend to do better in the hands-off department.
Still, there is that Pee Wee Judge crash to explain, and the problems associated with the absence of damping.

[Hognose]

Guys, I thought I posted this stuff in the thread before but I didn't. Happens when you have a whole computer lab and rotaryforum open on all the damn screens.

Steve --

I am glad you are still with us, appreciating the green grass of summer from the blade vice the root end. As you are probably aware, as you continue to research gyroplane stability, you had a beast of a close call. Close calls are God's (Nature's if you prefer) way of getting one's attention. Effective, innit?

I notice that the blockheads in the PFA even stopped Barry Jones from flying the latest Magni on his world trip. Greg, you might not have noticed this but he had a 2000 and they made him go back to a VPM 16 cause the 2000 isn't legal (if I have my model numbers right). Check it out at the globaleagle site. Here is a guy who makes British sport aviation look good, and they do everthing thay can to thwart him. My English relatives call guys like that (PFA, not Jones) "Jobsworth." I thought it was from a TV show or something but turns out it is what they say: "I'd like to help you, honestly, but it's more than my job's worth." Kinda like the PFA approach, "Sad business that people are dying in gyros that could readily be made safer, but our safety rules won't permit that. "

The attitude of the UK CAA is unbelievable. We certainly know how to make gyros stable and safe now. To deny pilots the ability to make their gyro safe to fly is criminal.

Greg, let me spin you up on how it works in Old Blighty, unique in all the world. Some nations are pretty liberal about homebuilt aircraft (USA, France, Canada are some). Some are rigid (Germany, Austria. Big surprize there, nicht wahr?) and some ban homebuilts (China, Cuba, Vietnam -- last gasp of Stalin's ghost). But in the UK the civil aviation authority, called, like ours (US) used to be, the Civil Aviation Authority, devolved authority for homebuilts onto the British equivalent of the EAA, the Popular Flying Association. This is much like the way that the US FAA does not micromanage sport parachuting, but permits the USPA to regulate the sport.

In this situation, there is a big incentive for the PFA to be rigid as hell. Unlike the CAA, they are not extensively staffed with professional engineers and inspectors; they run mostly by voluntary labour, as does our EAA or PRA. The PFA's driving nightmare is that they make some error and approve something that creates another Flying Flea situation and kills a bunch of Britons -- causing CAA to yank their charter. (Never mind that they already did the first part of this with early Air Command, and all CAA did was fund studies to find out why -- studies that benefited us all, if we read them).

So they (PFA technical) tend to accept the representations of manufacturers and their engineering data. (viz. RAF). Then, once they do, it is hell on earth to get them to change it. The reason they won't get around to looking at RAF stabs is that RAF says it is not OK and for them, RAF is the authority and sole authority on their machine. (Meanwhile, sensible RAF owners in the Americas have stabs and/or the AAI kit). The principle of primacy (remember all the junk you had to learn for the FOI test for your CFI? LOL) is hard at work in PFA.

Anyway, no subjective analysis will convince them. They will need hard engineering data, and reams of it, and it's a touchy personalities problem as well, because the engineering data will show, if poked and prodded a bit, that they have unsafe machinery flying in Great Britain, and THEY approved it (based, too be sure, on the lower level of stability and control knowledge most of us had X years ago).

So we have the paradoxical and unsatisfactory situation where the stabless RAF is approved, and high-thrustline Bensen clones are approved, but Magni needs a papal encyclical's worth of authority to get their latest machine approved vice the earlier one it's a derivative of, and an RAF owner who wanted to do the AAI mod would be refused: on grounds, ostensibly, of safety!

I have explained, I think, why it is that way. But it is no less retarded for being explicable.

cheers

-=K=-

[Hognose]

why don't you like Ken???
Would you say his machine is dangerous???[the one he constantly flys hands and feet off]

Birdy,

It's not that I don't like him. I don't know him personally, and I certainly admire his accomplishments and the favourable light he has put on our sport (which a few daft 'Strines seem to have made hard work out of!)

But -- he is mistaken on stability, and precisely because he is a living legend, his incorrect statements are dangerous, whereas you or I might say whatever nonsense came into our heads midway through a night of drinking, and do no harm because we're not legendary.

The thing is, a machine that has an overturning tendency in a particular corner of the flight/environmental envelope may fly for thousands of hours and tens of years without biting, if it doesn't go into that place, or if the problem requires particular weather or control inputs (or lack of same) to manifest itself. Meanwhile, the man or woman flying the machine develops a false sense of confidence. False because the dragon still lurks in that corner, waiting to strike.

I saw this when the Mini-500 killed a 35k hour helicopter pilot who had more real-world autorotations than you can shake a cyclic at, and more hours in the Mini than almost anybody (certainly more than the factory pilots, who barely flew the treacherous beast). The board called that one pilot error too, and in a way it was, but as Udi pointed out in this thread, (paraphrasing) a machine can make pilot error easy, or it can make pilot error hard. The human interface of the machine is an important aspect of the safety system.

Is there a dragon in the corner of one of Wallis's many machines? I don't know. They'd need a thorough weighing and measuring, along with some thought, to be sure. I have no beef with Ken Wallis bragging up his own machines and his own accomplishments. He's earned that right, I think we'd all agree. When he makes blanket statements about what stability and control requires, in reference to other machines than his own, he'd better be right.

Or I'm gonna call him on it, and I'm not the only one.

I'm not tearing him down, putting him down, or insulting him. I'm saying he's wrong. I have suggested his inflexibility on the issue may be due to his age, and perhaps that is taken as an insult. Like I said, I don't know the guy but I have sure seen a lot of people harden in their thinking as they got older. I'm extrapolating from that to Wallis.

These are no longer opinions but are established fact: (1) gyros need to be stable to be safe; (2) CLT is the most important factor in pitch stability; (3) most gyros need some kind of horizontal fin to be stable. Putting out contrary information is going to confuse people and might wind up killing them (you don't get hurt in a bunt-over; you die).

cheers

-=K=-

[Heron]

Few years back it was untinkable to challenge Dr. Bensen's findings and today many people will not go public on it!
They are only afraid of the harassment and bottering by the defenders of sacred cows
mistakes were made, not many responded for them . . .
Sometimes I provoke discussions without the proper knowledge just to get more out of the info avalilable and some people take this as insult or daring to get in to big dogs party . . .
Heron

[mceagle]

Quite a few years ago, one of our Civil Aviation Safety Authority Officers did his Gyroplane Licence in the USA so that he would be qualified to comment on the subject of Gyroplanes that were gaining popularity in Australia. He was a qualified and experienced test pilot in many species of aircraft, (including rotary wing) and travelled not only in Australia but all over the world as required to test and diagnose handling problems of different aircraft.
He completed his two seat time and did many solo hours in the training facility's early model single seat Air Command. On return he stated on record that the Air Command was quite a stable aircraft and that he would not support the compulsory fitting of a horzontal stabilizer to this aircraft.
I say this because I think that he was so experienced tuned to correct inputs (like Wallis) that he would automatically make the minute corrections necessary to avoid PIO. In fact such a pilot would be hard pressed to even induce PIO, and I feel that this form of "auto pilot" is often mistaken for auto-stability.

[jucie]

Exactly, Tim. That's why is so hard to talk about stability issues with some of the seasoned, most experienced gyro pilots.

[Aussie_Paul]

Tim, I remember that comment, and you are so correct. One of the best auto pilots is an experienced pilot in that particular aircraft.

At a fly in I asked an experienced gyroplane pilot of many years, the meaning of stability?

This guys answer was "the aircraft felt controllable and solid to fly". He was a very excellent stability "Auto pilot".

Aussie Paul.

[birdy]

Thanx for the reply Kevin.
You make alot of valid points.I gess I'v only read half the story on the man,and not his personal one.[gees,if a man like him gets a little "hard to budge" with age,there's no hope for a simplton like meself.]
I gess he knows his machine intimately,that's why it's so stable,for him.

And your last paragraph is the best I'v read on this forum to date.[I noticed the "MOST".]

[bpearson]

Many years ago a Wallis machine was based at a flying club. Any fixed wing pilot could fly it after being briefed. No wheel balancing I am told. Hundreds flew it with no problems.
I am not a 'Wallis is God' person, but that doesn't sound like a touchy machine to me. Also recall seeing a photo of him flying a dropped keel machine. He wanted a larger more efficient prop. What he came up with looked like a Dominator but he abandoned it because of the fragile undercarrige.....I think.

Brian

[stevek]

Hi Kevin.

Youv'e got a realistic grasp of the UK Gyro scene and the way it is controlled by the authorities. Most people in this country, both Gyro flyers and the authorities, must recognise the mess that we have got ourselves in to.

As you say, everything is geared to not 'rocking the boat' for fear of it becoming public knowledge that we are being coersed to fly sub-standard machines and hurdles are constantly being placed in the way of positive safety developments.

Having got ourselves into this mess, It's no good just bleating on about it and expect the situation to sort itself out. Someone needs to act as a catalyst to provide the incentives to start moving in the right direction - fast.

I have learnt my lesson about the limitations of my Gyro and came SO CLOSE to paying the price. There are still a large percentage (maybe the majority) who consider the UK unstabilized Gyro's to be satisfactory,because they will not admit to themselves that their machines are 'dangerous'. Their argument is that if you fly them correctly, then you should be OK - but remember to be ready for corrective action.

In truth, they all have a financial interest retaining the status quo, whether they are owners, instructors, manufacturers. - They don't want to let the cat out of the bag!

When I first published my incident, it was in the form of an email I sent to Martin Hollmann, explaining what happened and that I would like to purchase his book on Gyro design. He asked me if he could put my email on his site as a warning to others. This I agreed to.

Two days later, he had received correspondance from John Kitchin flaming him for publishing the email without knowing the whole facts and for potentially upsetting the UK gyro community. He had been in discussion with Mike Goldring (the UK RAF distributor) and Tony Melody (my instructor who is forced to provide 2 seat training in Mike's RAF2000 due to the non-availability of any other option) and had come to the conclusion that there was something wrong with me and that my experiences were invalid.

To be fair, Martin Hollmann replied to John Kitchin in no uncertain terms telling John - well I can't say here, but it made me chuckly!. I had a strick talking to from Tony Melody, saying that the matter had been brought up with the CAA, who now are insisting that I do 10 hours dual instruction in a RAF 2000 to demonstrate my competency. That's OK , but I am sure what benefits I will get being taught on another unstable gyro that handles so differently to my cricket.

I've wandered off track somewhat in the post, but I wanted you to understand where I am coming from and how self-defensive the UK scene is.

So what can I do ?

One route would be to get more of the UK pilots to join in discussions like in this forum - then I am sure most would see the potential problems and have a little better understanding of the subject. Such a large percentage have their own concepts of what stability is - normally wrong. They believe it is just a load of old bullsh*t that anoracks indulge in. These ignorant 'pilots' are just that - they do not understand the concepts of static and dynamic stability and so to avoid embarissment will dismiss someone trying to preach the subject, as 'an old woman' who should stock trying to rock the boat!.

Another route may be to take the risk of a exposing the whole issue in the UK press. I am sure that an interesting documentary could be made that would put some focus onto the issue by the authorites . - It may just get all non-section T grounded, effectivly killing the existing faltering gyrolane movement altogether.

Or perhaps just better working relations should be established - a working party or forum - with a strict agenda to establish a 'roadmap' to providing a workable system for the acceptance of safety modifications to existing Gyros and perhaps look at incorporating the proposed LSA flight test results (which can and should be done by all non section T gyro's - by their owners) and these results to be part of the aircrafts paperwork.

SO has anyone any input on the best direction for someone like me to go, to try and kickstart some action?

Are there any other UK gyro pilots who have some input to this? You can email me direct if you want to keep your opinions out of the public eye.

Is anyone from the authorities reading this who can see the problem and would like to get involved?

Come on everyone, don't be shy, we could save some lives here!.

Steve Kirkby

steve@gyroplanestability.com

[jucie]

Mike Goldring (the UK RAF distributor) and Tony Melody (my instructor who is forced to provide 2 seat training in Mike's RAF2000 due to the non-availability of any other option) and had come to the conclusion that there was something wrong with me and that my experiences were invalid.

Interestingly enough, too many experienced pilots blame new pilots lack of experience when something goes wrong. This attitude bring the focus away from what needs to be improved.

Another route may be to take the risk of a exposing the whole issue in the UK press.

Some years ago a reporter from BBC made a documentary named "Brazil: Beyond the Citzen Kane" that is a true BOMB! :eek: If you plan to follow that path, then BBC could be your better choice (if they keep that tradition). Be ready for much trouble. Maybe trying other paths first would be a better approach (but keep everything well documented, just in case you eventualy go to the press). Don't do it alone, join or create an association with as many interested people as you can.

Congratulations. Your initiative is very good.

[PW_Plack]

Steve,

Did they say your dual time had to be in GB? Maybe come over here on holiday, and get ten hours in an RAF with a stab? ;)

You know, the mainstream media is not likely to be interested in a topic of such narrow interest, and it's not necessary to use a medium which reaches 99.9 per cent non-fliers, anyway. Perhaps we could get a team together from within the gyro community, and produce a digital video for distribution on DVD and the internet. If it reaches would-be gyronauts, who cares how it gets there?

If we got Dan Leslie to work on video, I'd be happy to put my audio production experience to use, and maybe the AAI guys would agree it was a useful sales tool if they helped us do some instrumented demonstrations. Maybe you can prod the PFA into doing the right thing by threatening them with embarassment on an international scale. It would appear, from your recent experience, that they do take notice of such things, even if they're published outside Britain!

[stevek]

I hadn't considered looking into doing the 10hrs training abroad - it sound like a good idea in priciple. I do have a small logistical problem that I have chronic kidney failure and I need to connect myself for 8 hrs/day to a portable PD dialysis machine and would have to arange for supplies to be forwarde to my training destination. I waould also need to get a motel where I could have the suppleis delivered to and with a ground floor room, as I can't carry the kit upstairs - I have a circulation problem in my legs which limits me to walking at 100 yards at a time!. none of this effects my flying. Flying is now my last and only passion and I am not going to give it up just because of a knackered old body (well I'm 54 this year - but I feel old some times!)

I think your idea about producing a video/DVD is a great idea -I would like to get something along those line going, though I am not sure what practical help I could be. If the DVD was generic enough, demonstarting the bad effects of unstable Gyros, what can be done to make them stable and the handling charactristics of a sorted out Gyro, then you would imaging it would be a great sales tool for producers of mahchines that can be demonstrated to have all the stable charecteristics in the video. These could be given out toprospective purchasers - and then let market forces do the work. I have a number of high traffic websites and I could surely make it available for free download or as a streaming video and make it freely available for any interested pilots - with a little advertising in the GA press.

Where do we go from here?

Do we need to set up a working group? You sound as though you know some guys who may be haappy to get involved - I like it!

Steve Kirkby

[Aussie_Paul]

Hey Steve, Down uner is warmer when the UK and the US are cold. You could miss a winter!!!!!!!!!! :)

I am sure that we could handle those needs, if that's what you wanted to do. I am fortunate that I can train 7 days, and as many times per day as you can handle. I don't take on more than 1 full time student at a time, that way we get the best productivity.

I will find and post the Ballarat(where I live and operate from) web site so that you can conduct some research.

www.ballarat.vic.gov.au

Aussie Paul. :)

[stevek]

Paul,

Thanks for the generous offer, I surely appreciate it. I think it may just be a little far for me to arrange travel too. I have lways wanted to visit Oz, but I guess I shall have to wait for another life!

I understand you know my instructor - Tony Melody? Didnt he visit you with Mike Goldring, the UK RAF agent?

I am not too concerned about having dual instruction with Tony - It's just the principle and irony of having to be put in the position of having the instruction in an unstable Gyro - though if we havve to fly badly configured machines, it does make some sort of sense!.

An update - went to go flying today at Henstridge and saw Tony. he had been contacted by the CAA who want me to get intouch with one of their Doctor's. - I wonder what that's about? I guess I am being hit from all sides!

The potentially good news I heard today was the CAA and PFA have finally agreed to witness a test flight schedule on a Cricket Mk7 (which is undergoing Section T approval). This will be done with it's designed HS fitted and with a dummy fitted. The tests are to be done by three experienced instructors under the scrutany of the 'powers that be'.
It is to try and get some kind of agreement on the effects of a HS in flight.
Previously, they have wanted the Gyro to fully kitted out with transponders that measure everything (from stick forces, control position to accelorometers in all planes) This would have beeen an expensive operation for a private individual and where would you put all this kit without it effecting the performance of the test machine)

So maybe thay are starting to react to some of the pressure being applied from a number of fronts.

That's all for now, I'll keep in touch - and thanks again for your offer

Steve Kirkby

[Hognose]

Steve said: "Previously, they have wanted the Gyro to fully kitted out with transponders that measure everything (from stick forces, control position to accelorometers in all planes) This would have beeen an expensive operation for a private individual and where would you put all this kit without it effecting the performance of the test machine)"

Actually telemetry gear like that is surprisingly light now -- but you are right that it is quite expensive, as is the time of the sort of pros who can set it up.

AAI has done some testing in the Sparrowhawk along those lines... pretty fully instrumented. As I understand it the instrumentation is available to them when it is not being used in GBAs other programs, such as the Hawk 4 turbine gyroplane. At U of Glasgow they did testing with a VPM 16 (I think) that was not only fully instrumented but had adjustable thrust lines, etc. It's nice to see PFA finally moving in the direction of gyro safety rather than holding it back. I hope the results of the test are published in some easily accessible way.

cheers

-=K=-

[Hognose]

... an email I sent to Martin Hollmann... asked me if he could put my email on his site as a warning to others.

Damn me, I read that letter, Steve, and never put it together with this thread. (SFX: Heel of hand hittiing forehead). D'oh!

Two days later, he had received correspondance from John Kitchin flaming him for publishing the email without knowing the whole facts and for potentially upsetting the UK gyro community.

I don't know John Kitchin.

Martin Hollmann replied to John Kitchin in no uncertain terms telling John...

I *do* know Martin fairly well and I got a good howl out of this bit. Martin is a great guy... smart as they come. Opinionated and headstrong... yeah, another one of those self-effacing and modest pilots and designers that have become an archetype. ;) You just have to remember that the Germans invented everything, and you and Martin will get on like a house afire. Seriously, though, Martin is not always right but I would never bet against him on anything to do with aerodynamics or structures, because he's almost always right, which I think beats my average.

There is some very good stuff on Martin's site. The paper his son did has given me many hours of entertainment trying to keep track of all the variables... ¡Ay Chihuahua!

... talking to from Tony Melody...the CAA... now are insisting that I do 10 hours dual instruction in a RAF 2000 to demonstrate my competency.

Gee, some lucky instructor just got handed £1000 of work by the CAA. Who do we know instructs on an RAF in GB... hey... after a nationwide search, I come up with Tony Melody.

Now, that's a remarkable coincidence, innit?

Much of this problem would not happen if PFA did not try to be a tin god and make an experimental amateur-built craft the equivalent of a certificated one in safety (not to mention paperwork). In the certified world, a plane doesn't get into the air until you drop its own weight of documents on the other end of the see-saw.

Not merely wanting to snipe, I'd like to make a positive suggestion. If the PFA could specify in advance what technical details it would like to review for approval, then kit and plans developers could test conforming prototypes against the specific criteria required for certification.

cheers

-=K=-

[stevek]

AAI has done some testing in the Sparrowhawk along those lines... pretty fully instrumented. As I understand it the instrumentation is available to them when it is not being used in GBAs other programs, such as the Hawk 4 turbine gyroplane. At U of Glasgow they did testing with a VPM 16 (I think) that was not only fully instrumented but had adjustable thrust lines, etc. It's nice to see PFA finally moving in the direction of gyro safety rather than holding it back. I hope the results of the test are published in some easily accessible way.



-=K=-

I shall be there, and I know 2 of the pilots involved in the flight tests, so I will report back here how the day appears to go.

steve kirkby

[stevek]

Damn me, I read that letter, Steve, and never put it together with this thread. (SFX: Heel of hand hittiing forehead). D'oh!



I don't know John Kitchin.


-=K=-


John Kitchin is one of the UK's old time pilots and stirrers. He has in the past done some good work for the Gyro community. He was a retired BA commercial pilot on 747's and the like, and used to own the Campbell gyroplane company. He was always doing display work at airshows in his Brithish Airways sponsered Cricket ( recently rebuilt for a TV program).

He found (when he got into Gyro's - 25+ years ago) that there was a movement flying these machines in our West country that were doing so off their own bat . (no training, liscences or any kind of supervision)

He put together with the CAA a framework for the formalizing of the flying, with training schedules etc - and generally straightened up the UK scene.

He was a exceptionally good display pilot but I question his competency in Gyro design and engineering.

Being in the position he is in and his history, his words are taken seriously by the old school authority figures. He hasn't flown now for 20 years - that am aware of, but still likes to put is oar in ocassionally.

I got on well with the guy, but he probably doesn't remember me. When he retired 20 years ago, he moved to Majorca to live on his boat and I have only seen him once since then.

Steve Kirkby