The real causes of RAF-2000 accidents

[gyroguy]

One reason there are so many lurkers on Rotorcraft Forum is they are afraid to speak up. I think they feel that regardless of what they post, someone will flame them, roast them, insult their intelligence, and show the whole forum what idiots they are.

This is America. Anyone has a right to build any kind of experimental aircraft he or she wishes, including completely stock RAF-2000s. He has a right to ignore whatever anyone except FAA says about his machine. He has a right to express his opinion about it and anything to do with it on this forum. He has a right, if flamed and insulted, to never come back to this forum again. If you don’t want him, why should he listen to you?

Some forums I know of are actually helpful to newbies and to people willing to express an opinion that runs contrary to what the majority of posters post. Their posters with big posting numbers have minds broad enough to consider something that might threaten their preconceived notions. Contrary opinions don’t even threaten their manhood.

From watching threads that mention RAF accidents on this forum, I see a trend. First there are the basic facts of the accident. Next come condolences, which it’s unlikely family members see. Then come pages and pages of flaming RAF design flaws, touting aftermarket fixes, and ranting anti-RAF propaganda.

The feeling I get from this forum is that if an RAF-2000 hit a runway light while taxiing, it would be because it had no horizontal stabilizer and was unsafe to fly. We’d never hear from RAF pilots, whose personal experience might give us tips to prevent that from occurring again. We wouldn’t hear from them because malicious posters on this forum have run them off.

Yep, I know RAF has design flaws. If you’re a gyro pilot who doesn’t fly RAF gyros, your gyro probably has design flaws, too. Mine does.

What is missing is AN ACCIDENT CAUSE! We see the little pictures of a crashed gyro. What we don’t see are the details you could go up and touch – if you were there. And since none of us was there, anything we post about why the accident happened is idle speculation.

So, can you posters please wait until there’s good information on the causes of an RAF accident before you assume it was caused by "RAF design flaws?"

--Kerry Cartier
Wills Point, Texas

[dragonflyerthom]

One reason there are so many lurkers on Rotorcraft Forum is they are afraid to speak up. I think they feel that regardless of what they post, someone will flame them, roast them, insult their intelligence, and show the whole forum what idiots they are.

This is America. Anyone has a right to build any kind of experimental aircraft he or she wishes, including completely stock RAF-2000s. He has a right to ignore whatever anyone except FAA says about his machine. He has a right to express his opinion about it and anything to do with it on this forum. He has a right, if flamed and insulted, to never come back to this forum again. If you don’t want him, why should he listen to you?

Some forums I know of are actually helpful to newbies and to people willing to express an opinion that runs contrary to what the majority of posters post. Their posters with big posting numbers have minds broad enough to consider something that might threaten their preconceived notions. Contrary opinions don’t even threaten their manhood.

From watching threads that mention RAF accidents on this forum, I see a trend. First there are the basic facts of the accident. Next come condolences, which it’s unlikely family members see. Then come pages and pages of flaming RAF design flaws, touting aftermarket fixes, and ranting anti-RAF propaganda.

The feeling I get from this forum is that if an RAF-2000 hit a runway light while taxiing, it would be because it had no horizontal stabilizer and was unsafe to fly. We’d never hear from RAF pilots, whose personal experience might give us tips to prevent that from occurring again. We wouldn’t hear from them because malicious posters on this forum have run them off.

Yep, I know RAF has design flaws. If you’re a gyro pilot who doesn’t fly RAF gyros, your gyro probably has design flaws, too. Mine does.

What is missing is AN ACCIDENT CAUSE! We see the little pictures of a crashed gyro. What we don’t see are the details you could go up and touch – if you were there. And since none of us was there, anything we post about why the accident happened is idle speculation.

So, can you posters please wait until there’s good information on the causes of an RAF accident before you assume it was caused by "RAF design flaws?"

--Kerry Cartier
Wills Point, Texas


Good Point Kerry.


Thanks for your input.

[Chuck_Ellsworth]

Quote from Kerry:

---------------------------------------------------------------------------------------------------------


and ranting anti-RAF propaganda.

----------------------------------------------------------------------------------------------------------------


Dictionary.com Unabridged (v 1.1) - Cite This Source - Share This
prop·a·gan·da /ˌprɒpəˈgændə/ Pronunciation Key - Show Spelled Pronunciation[prop-uh-gan-duh] Pronunciation Key - Show IPA Pronunciation
–noun
1. information, ideas, or rumors deliberately spread widely to help or harm a person, group, movement, institution, nation, etc.
2. the deliberate spreading of such information, rumors, etc.
3. the particular doctrines or principles propagated by an organization or movement.
4. Roman Catholic Church.
a. a committee of cardinals, established in 1622 by Pope Gregory XV, having supervision over foreign missions and the training of priests for these missions.
b. a school (College of Propaganda) established by Pope Urban VIII for the education of priests for foreign missions.
5. Archaic. an organization or movement for the spreading of propaganda.

Kerry, what makes you accuse some of us of the above, do you deny physics?

[barnstorm2]

Kerry,

As the PRA Safety Guy you have written a number of acclaimed articles on this topic. All of these that I have read seem to appeal to newbies and ol-timers alike.

Why don't you start some new threads aimed at newbies and lurkers and post some of your articles?

I think that would be a fantastic contribution to the forum.

If you are worried about starting up another 'heated' discussion why don't you suggest that no one post in your thread that has a post count of more than say 200 posts?

In any case, thanks for your input.

.

[Larry Boyer]

Kerry. Right on!!! Chuck. True to form.

[C. Beaty]

Walks like a duck, quacks like a duck; it’s a rabbit!

[Walter]

So I have less than 200 posts, do not fly a RAF and have, I think, no vested interest in this matter. My question:
Why are not statistics used to assess the risk? Insurance companies use statistics to determine the height of insurance rates. Even a limited data set will give an independent, unbiased estimate.
How many RAF`s fly out there in relation to all other types and what is the accident ratio? Any estimates? Any correlation with horizontal stab?

-Walter

[chuter]

I think that one reason we engage in so much guessing as to what causes these accidents is because we rarely get a timely and accurate report through official channels.

I don't think I'll ever see a report from the NTSB or FAA that says "accident caused by pilot's failure to maintain dynamic stability in the absence of horizontal stabilizer, leading to PPO caused by uncompensated high thrustline".

[BUD ONEAL]

I think that one reason we engage in so much guessing as to what causes these accidents is because we rarely get a timely and accurate report through official channels.

I don't think I'll ever see a report from the NTSB or FAA that says "accident caused by pilot's failure to maintain dynamic stability in the absence of horizontal stabilizer, leading to PPO caused by uncompensated high thrustline".



No one has given them a education on gyros. I'd bet that not one in fifty knows anything about gyros. The fesico[sp] with Bill in Wauchula 06 has me convinced of that

[Doug Riley]

The FAA investigation of the Air Command PPO crash here in Vermont a couple years ago included a sound analysis of the cause of PPO.

It's true that most such reports here in the U.S. don't assign a cause more specific than loss-of-control or other conclusory language.

[PTKay]

Gyroguy,

you ask for The real causes of RAF-2000 accidents ?

Try this.

http://www.aaib.dft.gov.uk/cms_resources/RAF%202000%20GTX-SE,%20G-REBA%2009-07.pdf

This is no flaming, no bashing, no propaganda.

Proper professional accident analysis.

Good enough for you ???

[EI-GYRO]

If the PRA hasnt got enough data on the RAF's gory history at this stage,
it never will.
If it does nothing to address the glaring deficiencies of this murderous
machine in its stock form, it might as well hang up its hat right now.

[C. Beaty]

Just to clear things up, Fergus, the PRA, unlike its counterparts in the UK and Australia, has no quasi-official standing with the FAA. In that respect, it is no different than any other lobbying group.

Rusty Nance, the current president and Greg Gremminger, the current vice president, are both knowledgeable about gyroplane theory and are well aware of the deficiencies of the RAF.

But all they can do is lobby and there’s no guarantee the FAA will listen. In fact, the FAA is more likely to listen to their former employee, Martin Weaver than to Rusty or Greg.

[PTKay]

But all they can do is lobby and there’s no guarantee the FAA will listen. In fact, the FAA is more likely to listen to their former employee, Martin Weaver than to Rusty or Greg.

How sad...

:(

And they certainly will not listen to those "stiff upper lip" Britons from CAA
or even less, to the Canadians...

[EI-GYRO]

I was aware of the PRA's status, Chuck, or lack of it.
It should however, lobby as hard as it can with the FAA.
More importantly, it should also lobby or at least educate its membership.
What Kerry started this thread with seemed suspiciously like, 'lets not
rock the boat until the report is in.' At which point, of course, the boat has
long since disappeared over the horizon.
Whether this most recent accident was PPO or not, the accumulated history
of this design, in its stock form, is more than sufficient to warrant serious
warnings to whatever audience you have.
And particularly to high-time fixed-wing pilots.

[PTKay]

Don't you think the factory LSA will clean the market.

Like class T in UK, it will (or already has)
clearly defined stability criteria and test procedures.

Greg did a lot in this subject...

[Steve McGowan]

Should the FAA listen to the PRA...HUH??

The biggest subject within the membership is WHO owns Mentone Airport..
We humans don't own anything, not even the clothes on our backs.
The members drop out because of a 50.00 per year fee.. WHY I'd like to know.

The people that are working to get something done is run in the ground by the WIZARDS of KNOWLEDGE on this forum..Hell if it were up to them,, we'd all be internet pilots.

The FAA monitors the forum, they see whats being said and by whom, so
Until everyone sticks together on something,
NOTHING will be noticed by the FAA, except the foolishness..

Happy New Year,,,,,,,,,,,,I'm goin Flying

in a Gyro Mr KAY.....Not a FW

[animal]

Happy new years Steve, Enjoy your flight.

I may have to see about comeing out your way and doing some flying with you sometime.

I think some more time in an open frame machine might do me good on my landings.

I have 14 hours in Gary Neal's RAF-2000 and I still can't land.

I have been told by another Forum memeber,That has time in Gary's gyro that his is tricky to land and they Suggested I get some time in your machine sometime also.

[pwendell]

Some forums I know of are actually helpful to newbies and to people willing to express an opinion that runs contrary to what the majority of posters post. Their posters with big posting numbers have minds broad enough to consider something that might threaten their preconceived notions. Contrary opinions don’t even threaten their manhood.


Wills Point, Texas

To plagiarize Jim Mayfield, "Stability is not an opinion".

The RAF 2000, in its stock form, is unstable.

In this recent crash, the aircraft fell out of the sky in a way that makes PPO, the result of the RAF's known instability, a likely cause.

We will never 'know' for sure what caused it. I hope we learn more than we do now, but we may not. I don't think it is unreasonable for those who are tired of this senseless and unnecessary loss of human life to speak up about the known dangers of a stock RAF in the wake of this accident.

Anyone is welcome to express any theory about the RAF's flight characteristics on this forum, but they should be willing to back up their theories with data and reasoning from sound scientific/aerodynamic principles.

[PTKay]

The FAA monitors the forum, they see whats being said and by whom, so
Until everyone sticks together on something,
NOTHING will be noticed by the FAA, except the foolishness..



I would be glad if FAA would monitor the development of gyrocopters
in other countries, instead of this forum.

Especially the scientific research done in UK
and recent AAIB reports on RAF 2000.

Why FAA cannot learn from CAA ???

Go learn something Steven, before going flying.

It, sometimes, help....

[birdy]

The FAA monitors the forum, they see whats being said and by whom, so
Until everyone sticks together on something,
NOTHING will be noticed by the FAA, except the foolishness..

So, your sayn that, if you all agree, wether you all rite or all rong, they'll back you??
Dont any of these people have brains of their own??

[Fl90]

Not really, brains are a burden....and yes they'd be happy to back you, if it presented well and agreed by the majority, they'd certify dangerous aircraft....wait, the already did.

Phil.

[Heron]

C´mon Lurkers, it is like sex . . .only hurts the first time! (pop goes the can or worms) :D
RAF´s can fly stable . . .untill they snap . . .then you die!
Heron

[Udi]

...RAF´s can fly stable . . .untill they snap . . .then you die!
Heron
Wow, Heron. If only all your posts could be this short and to the point. And so true!!!

This gold nugget from Heron is the precise reason most RAF pilots don't think anything is wrong with it - until it's too late.

Udi

[Steve McGowan]

I would be glad if FAA would monitor the development of gyrocopters
in other countries, instead of this forum.

Especially the scientific research done in UK
and recent AAIB reports on RAF 2000.

Why FAA cannot learn from CAA ???

Go learn something Steven, before going flying.

It, sometimes, help....


It's Steve ,,,, not Steven....

Learn this Kay,,, I don't report to you or need to pass any of your test.

I learn from those that show me knowledge, Not someone that stays on a computer running they're mouth as you and others do..
You Sir ,,show me the reason polish jokes are made..

Thankyou But NO Thankyou

[automan1223]

Kerry,

If I had a full set when I got into this sport several people might be alive today. I was too worried about fitting in and what other people might think of me. Now I have grown up (some might disagree) and I really do not care whose feelings I hurt or turn off if it involves a safety issue. If more people ranted and raved and took the "keys" away from RAF pilots (and others) there might be a few more souls in this sport. There is really no polite way to address the "attitude".

RAF owners / pilots are like a cult. They have their religion and no matter what you say to them they are going to stick their head in the sand and la la la la all the way, ignoring what we have said over and over and over again. They will ignore the accidents, they will think they are better than the last stick who put it in the ground.

There is only one reason why RAF's keep falling out of the sky, if there was another reason we would have discovered it by now, at least I am pretty sure we would have evidence of something else, mechanical, medical reasons etc. Having been reading forums since 1999 all of the RAF accidents sound the same. Dead pilot-s, open field. wreckage, tail missing or in pieces.....do not think I ever read about an RAF fatal over a rwy light.

With all this modern communication it is a crying shame those that need the message the most fail to listen. Economics or Pride, the only reasons why we have rock stock RAF's killing pilots and 9 y.o boys. It is a free country but this sport will go down as in death by association. Unless we keep beating the drum about HTL vs. I REFUSE to be polite and be lumped into that group that gives us that horrible safety record. I am going to bitch, moan, whine and complain every time I see another senseless death.

I do not run with an open pair of scissors, #2 pencils. Light fireworks with short fuses and I certainly do not ignore physics when my rear end, over 130 hp and speed is involved. But there are those that do and will. It is a never ending story and a never ending list of widows.

J

[jvitable]

To All Out There-The opinions of those that have no actual experience in a RAF are worthless to me--I have flown stock RAFs with no problems-great machine-AND believe me I am not a great pilot-I had A stock Air Command/with stab-great machine- no hands or feet needed in cruise--Maybe its because I fly in good weather plus I have over 40 hrs of training in different machines--30 of that in a stock RAF-no matter how much time the pilots in these crashs had(some)-(they )failed to remember the first rule of flying any gyro-----WHEN IN TROUBLE-FULL BACK THE POWER AND LIVE -I now own a RAF with STAB with WINGLETS-BUT I KNOW THE STAB IS NOT A REPLACMENT FOR GOOD TRAINING-Joe---281-489-2019

[Chuck_Ellsworth]

So when you buy one of Ernies Dominators does Ernie make sure you know ......


they )failed to remember the first rule of flying any gyro-----WHEN IN TROUBLE-FULL BACK THE POWER AND LIVE -

[Timchick]

To All Out There-The opinions of those that have no actual experience in a RAF are worthless to me--I have flown stock RAFs with no problems-great machine-AND believe me I am not a great pilot-I had A stock Air Command/with stab-great machine- no hands or feet needed in cruise--Maybe its because I fly in good weather plus I have over 40 hrs of training in different machines--30 of that in a stock RAF-no matter how much time the pilots in these crashs had(some)-(they )failed to remember the first rule of flying any gyro-----WHEN IN TROUBLE-FULL BACK THE POWER AND LIVE -I now own a RAF with STAB with WINGLETS-BUT I KNOW THE STAB IS NOT A REPLACMENT FOR GOOD TRAINING-Joe---281-489-2019

This is exactly the attitude Jonathan just mentioned. Science and physics mean nothing.

[gyroplanes]

So I have less than 200 posts, do not fly a RAF and have, I think, no vested interest in this matter. My question:
Why are not statistics used to assess the risk? Insurance companies use statistics to determine the height of insurance rates. Even a limited data set will give an independent, unbiased estimate.
How many RAF`s fly out there in relation to all other types and what is the accident ratio? Any estimates? Any correlation with horizontal stab?

-Walter

Walter,
We have an insurance problem that rivals the stability problem and both are a result of the size and sample of our numbers.

We have no idea of how many gyros are currently flying in the USA, we also don't have a clue as to how many hours they fly. Gyroplane pilot's have long been the leaders in illegal flying, probably only recently surpassed by powered parachute owners.

A fair guess is that the RAF probably leads in both sales and hours flown. They probably also lead in fatalities. This would not trigger an FAA alarm.

Two of the last three fatal accident RAF's had horizontal stabilizers. What does this appear to tell you? What would it suggest to the FAA?

The FAA knows more about us and our problems than you imagine. My biggest fear is that they might get involved.

[gyroplanes]

Not really, brains are a burden....and yes they'd be happy to back you, if it presented well and agreed by the majority, they'd certify dangerous aircraft....wait, the already did.

Phil.


Phil,
The FAA doesn't certify the airworthiness of experimental aircraft, the builders do.

[gyroplanes]

If the PRA hasnt got enough data on the RAF's gory history at this stage,
it never will.
If it does nothing to address the glaring deficiencies of this murderous
machine in its stock form, it might as well hang up its hat right now.

As Chuck B stated, the PRA has no jurisdiction over the permit to fly.

The FAA does not establish the airworthiness of experimental aircraft, the builder does.

Neither the PRA nor the FAA has any idea of the actual number of gyros flying, the hours flown or the accident rate of any model.

The FAA is charged with aviation safety and can do almost anything they want in the interest of safety. The FAA's primary goal is protection of innocent civilians on the ground and ignorant passengers.
I'd rather wish they would stay out of this fight, they are an awfully big pendulum and once moving they tend to overshoot their mark. I'd prefer we had the right to kill ourselves, than lose our right to fly.

[gyroplanes]

Don't you think the factory LSA will clean the market.

Like class T in UK, it will (or already has)
clearly defined stability criteria and test procedures.

Greg did a lot in this subject...


As it stands right now, the ELSA gyroplane will end in 30 days. SLSA gyroplanes never were.

I believe compliance the ASTM standards the industry wrote will do a lot for the safety of gyroplanes. Without SLSA & ELSA gyroplanes though, ASTM standards are just suggestions and not regulatory.

[gyroplanes]

To plagiarize Jim Mayfield, "Stability is not an opinion".

The RAF 2000, in its stock form, is unstable.

In this recent crash, the aircraft fell out of the sky in a way that makes PPO, the result of the RAF's known instability, a likely cause.



Peter,
When it comes to the FAA, stability IS an option.

The FAA has different stability requirements for different categories of certificated aircraft.

We have semi-stable aircraft, very stable aircraft and aircraft so unstable that only a computer can fly them and they are flying over your head right now.

We don't want an stable Pitts Special or FA-18 Hornet, but there's absolutely no reason to build or fly an unstable gyroplane.

[PTKay]

You Sir ,,show me the reason polish jokes are made..

Thankyou But NO Thankyou

OK, this forum has hit the rock bottom....

I just would like to see, when the "Polish joke" Xenon
will wipe out of the market all the contraptions like RAF...

Live long Steve, and dream on your dream...

The reality (and the laws of physics)
will catch you sooner or later.
I just wish you, it will not happen in flight.

It's EOT on my side, I already once left from here,
on a "Polish joke" case, hoped it was an exception,
now it seems to be a rule.

[gyroplanes]

Rusty Nance, the current president and Greg Gremminger, the current vice president, are both knowledgeable about gyroplane theory and are well aware of the deficiencies of the RAF.



Chuck, Rick Marshall is the current PRA VP

I just wanted to give due credit to another volunteer working for us.

Greg continues to work (even harder) on our behalf.

[Arnie Madsen]

I would be glad if FAA would monitor the development of gyrocopters
in other countries, instead of this forum.

Especially the scientific research done in UK
and recent AAIB reports on RAF 2000.

Why FAA cannot learn from CAA ???

Go learn something Steven, before going flying.

It, sometimes, help....

Hi PTKay . I enjoy your input . Thanks.
I came across this report on the NSTB site .Maybe the FAA knows a bit more than we give them credit for.

---------------------------------------------------------------------
QUOTED FROM: From NSTB report:
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20020712X01113&key=1
=====
............The FAA's Rotorcraft Flying Handbook contains a discussion of pilot-induced oscillation (PIO), and power pushover situations.
The handbook notes that gyroplanes experience a slight delay between control input and the reaction of the aircraft. This
delay may cause an inexperienced pilot to apply more control input than required, resulting in a greater aircraft response
than was desired. Once the error has been recognized, opposite control input is applied to correct the flight attitude. Because
of the nature of the delay in aircraft response, it is possible for the corrections to be out of synchronization with the movements
of the aircraft and aggravate the undesired changes in attitude. The result is pilot-induced oscillations that can grow rapidly in
magnitude. A power pushover, as described in the FAA handbook, may result if rotor force is rapidly removed, producing a
tendency to pitch forward abruptly. This is often referred to as a forward tumble, buntover, or power pushover. Removing the
rotor force is often referred to as unloading the rotor, and can occur if pilot-induced oscillations become excessive. A power
pushover can occur on some gyroplanes that have the propeller thrust line above the center of gravity and do not have an
adequate horizontal stabilizer. In this case, when the rotor is unloaded, the propeller thrust magnifies the pitching moment
around the center of gravity. This nose pitching action could become self-sustaining and irreversible.
-------------------------------------------------------------

The next time someone questions RAF stability maybe we should all just lead them to this FAA statement.

Maybe we should prompt the FAA to send an advisory alert to all current RAF owners and builders quoting the above.

How many deceased RAF pilots would still be alive if officially warned by the FAA about stability issues. Most I would think.


Arnie Madsen
Bell 47 G2

[Fl90]

Tom, I was refering to certified aircraft, GA and passenger, that have been designed with inaproprite airfoils and faulty systems.

It was in respose to the post previous.

The FAA has to take the design engineers word as printed. Obviously, if the personel working for the FAA were educated and adequate to design aircraft, that's what they'd be doing. And, NO, that's not a dig, and that doesn't mean they are uneducated. But, to catch a design flaw before certifying, you'd have to be more experienced and more educated than the designer.

Phil.

[Heron]

I may have to go back and read again a couple os posts but . . .I think PTkay and Steve misunderstood each other. Cool guys . . .cool . . .
I have one question to add:
All the RAF pilots out there . . .what do you have to learn to compensate the problem and how often you have to use that skill to keep right side up?
Second:
What happens if you miss the time to apply the correction?
I think honest answers will quantify the problem and its range of near misses.
thanks
Heron

[Sir Real]

I did a compilation of gyro accidents from the NTSB website about 6 months ago. It was raw numbers only, and did not take into account the number of given models flying vs the number that are no longer flying due to unfortunate occurences. However, the number of RAF crashes was much higher than any other model. The next highest number was Air Command, and I believe that there are more ACs flying, and flying longer, than RAFs, which would make the RAF accident per craft or per hour ratio much higher. I don't pretend to know why any of them crashed, beyond what the NTSB reports say (and NTSB reports tend to paint with extremely broad strokes), and I didn't go into it with any preconcieved notions, lacking the experience to form them, but having looked at the numbers independently, I know that I will never fly, or fly in, an RAF. Otheres will do as they will, of course, and most will likely be safe. Me, I'm an inveterate coward.

Or is that invertebrate?....

[C. Beaty]

Arnie, the FAA flight manual was written by a subcontractor; Jeppesen. The FAA’s ground rule was: speak no evil.

Much of the technical input was provided to Jeppesen’s tech writer by Dr. Bill Clem, who at one time held the official altitude record in his Dominator.

[gyromike]

As it stands right now, the ELSA gyroplane will end in 30 days. SLSA gyroplanes never were.

I believe compliance the ASTM standards the industry wrote will do a lot for the safety of gyroplanes. Without SLSA & ELSA gyroplanes though, ASTM standards are just suggestions and not regulatory.

Tom,

How are the Xenons getting around the 51% rule?

[ScottTinnesand]

Hi Mike,
I know you directed your question at Tom, but I do know the answer.

The Xenon isn't getting around the 51% rule, it's certified through a different rule. A very incomlpete summary is that the Xenon gets its airworthiness certificate through the ELSA Conversion rule (that happens to expire this month). Xenon has requested an exception to the rule to continue after this month. Hopefully there will be an answer sometime soon!

Scott

[gyroplanes]

Scott is correct. Thanks Scott.

[Doug Riley]

To Kurt (Sir Real): There's little difference in PPO susceptibility between an original Air Command and an RAF.

An early Air Comm has either no HS or a very small one, and a thrustline offset (above CG) of about six inches WITHOUT the pod. (It would be somewhat more with the pod.) Prop thrust is about 300 lb. Gross is about 600 lb.

A stock RAF has about a 12" thrustline offset, no HS and 600-plus lb. of prop thrust. Gross is about 1200 lb.

From the PPO viewpoint, the RAF is the equivalent of a scaled-up Air Command. Again, both are quite prone to PPO, and for the same reasons.

RAF catches more flak here because, rather than fix the problem as Air Command did, RAF engaged in quite a vicious campaign of disinformation with the goal of maintaining sales of the original model. Some people absorbed the disinformation as if it were accurate technical data. Now they just won't let go of this junk science, even though the RAF company no longer sells gyros.

Happily, Air Command revised its design long ago. There have been no PPO accidents with the CLT Air Command. Too bad RAF didn't do the same thing early on.

[barnstorm2]

To All Out There-The opinions of those that have no actual experience in a RAF are worthless to me--I have flown stock RAFs with no problems-great machine-AND believe me I am not a great pilot-I had A stock Air Command/with stab-great machine- no hands or feet needed in cruise--Maybe its because I fly in good weather plus I have over 40 hrs of training in different machines--30 of that in a stock RAF-no matter how much time the pilots in these crashs had(some)-(they )failed to remember the first rule of flying any gyro-----WHEN IN TROUBLE-FULL BACK THE POWER AND LIVE -I now own a RAF with STAB with WINGLETS-BUT I KNOW THE STAB IS NOT A REPLACMENT FOR GOOD TRAINING-Joe---281-489-2019

Joe,

I am glad you have the HStab, buy why? If you have installed the HStab you thus must have at least some understanding of the issue?

Closing the throttle is no answer. A PPO event takes only about 1 second to happen. Do you really think that by the time you 1. figure out what is going on and then 2. Take action that LESS THEN ONE SECOND HAS GONE BY?

What makes you think you are better and more skilled then the multi-thousand hour CFIs and other pilots that have been killed in PPOs?

Do you understand how the offset-gimble provides a LIMITED FELLING of stablity but does not actually make the RAF stable? If so please show us by explaining it here to us. You know your RAF you would know how it's componets work right?

There ARE people with RAF's recommending that no one fly the stock RAFs, arn't you listening?

I hope to God you are not taking up any passengers with that kind of attitude toward learning, safety and aerodynamics even if you do have an HStab.

With your attitude toward safety, learning and pilotage you are a threat to yourself, your passengers, this sport and anyone or thing you fly over.

-----

Jonathan,

Excellent post.

[Jon F]

Mr. Riley:

The Rotary Forum has discussed RAF stability back and forth nearly endlessly.

But all of the arguments are qualitative or anecdotal (essentially opinions).

Dr. Hollmann has published some work on pitch stability of gyroplanes in a quantitative way and I believe there was an analysis of gyroplane stability done in the UK.

Has anyone attempted a quantitative stability analysis of the RAF?

The ability to judge a design using computer analysis would provide unbiased results and help move us toward safer machines.

Thank you for all the great posts.

Jonathan Fant

:wave:

[Gary_in_Orygun]

...

This is America. Anyone has a right to build any kind of experimental aircraft he or she wishes, including completely stock RAF-2000s. He has a right to ignore whatever anyone except FAA says about his machine. He has a right to express his opinion about it and anything to do with it on this forum. He has a right, if flamed and insulted, to never come back to this forum again. If you don’t want him, why should he listen to you?

Some forums I know of are actually helpful to newbies and to people willing to express an opinion that runs contrary to what the majority of posters post. Their posters with big posting numbers have minds broad enough to consider something that might threaten their preconceived notions. Contrary opinions don’t even threaten their manhood.

From watching threads that mention RAF accidents on this forum, I see a trend. First there are the basic facts of the accident. Next come condolences, which it’s unlikely family members see. Then come pages and pages of flaming RAF design flaws, touting aftermarket fixes, and ranting anti-RAF propaganda.

The feeling I get from this forum is that if an RAF-2000 hit a runway light while taxiing, it would be because it had no horizontal stabilizer and was unsafe to fly. We’d never hear from RAF pilots, whose personal experience might give us tips to prevent that from occurring again. We wouldn’t hear from them because malicious posters on this forum have run them off.

Yep, I know RAF has design flaws. If you’re a gyro pilot who doesn’t fly RAF gyros, your gyro probably has design flaws, too. Mine does.

What is missing is AN ACCIDENT CAUSE! ...

So, can you posters please wait until there’s good information on the causes of an RAF accident before you assume it was caused by "RAF design flaws?"

--Kerry Cartier
Wills Point, Texas

Wow! What good insight, good observation, and good advice. Thanks Kerry. EMOTION plays a big part of people going off at the keyboard before the facts are in. Because a 9-year-old was involved, the EMOTION factor was even higher on the Texas accident.

I know what I fly, and I know there are ways to make it more stable. It would be nice if all RAF'ers understood the ramifications of a high-thrust line. Once understood, at least they would be making informed decisions on whether to add a horizontal stabilizer or not.

And yes, it is true that when flying a high-thrustline machine if you get light in your seat, retard the throttle before the next blink of your eye. I've said most of this before. I enjoy my freedom to fly what I want. Those that tell me I'm wrong or stupid have done me an injustice, because human nature is to shut down with that kind of input and possibly miss some good data.

But in the tone that Kerry set, if the facts are presented calmly without the emotional BS, then maybe more stock RAF'ers will see a benefit to adding a little PPO insurance with a H-stabilizer, and maybe even more with a few other mods.

[barnstorm2]

Jon F,

Are you aware of the CAA study and resulting limiations on STOCK RAF gyroplanes in the UK?

[barnstorm2]

Gary,

Thanks to your signature line every time you post you show you are a RAF owner and pilot that understands the stability issue and has taken both corrective action with your machine and in your pilotage.

You are a candle in the darkness.

I find it an interesting study in pilot/owner/human behavior that we don't have a community of AirCommand Classic owners in the hobby claiming that people should be flying stock, stabless HTL AirCommands and that training is somehow the magic cure for the flaw in the machines... why?

I think the "Why?" is because the AirCommand company and the CFI's it sponsors/ed came to understand the problem and fixed it. They even publicly state when you call them or browse there web page that an AirCommand without an HStab is UNAIRWORTHY.

When I got my first gyro it had NO STAB. I wonder today what might have happened if when I called AirCommand Doug Smith had not told me my aircraft was unairworthy until I at least install an HSTab and that to make the machine fully compliant with current AirCommand safety standards I would need to install the CLT kit?

With the original RAF CFI's still admonishing stability and HStab or at best just silent on the issue, NuRAF's website claiming STOCK RAFs to be the pinnacle of safety and engineering and RAF owner websites silent on the issue.....

well.. that kind of just leaves you..... without any RAF 'authority' figure as a role model for being smart, responsible and safe.

All of the 'official' RAF authority figures are either quiet on the issue or blatantly mis-inform.

If you guys, the smart RAF owners don't push for a change in the RAF communities I don't see much hope other than attrition.

The rest of the gyroplane community as tried to educate STOCK RAF owners with everything from cute statements and t-shirts to absolute outrage and past a certain point it all falls on deaf ears.

Even with some RAF owners like yourself showing a GREAT example still people like joe "jvitable" claim they are too block headed to listen to anyone but another RAFer (but it looks to me that he won't even listen to other RAFers unless they have the same magical thinking as he does).

You guys need to get vocal. RAFers for a safe stable RAF!

[Doug Riley]

Jonathan:

My post contained the numbers you need to calculate PPO moment for both the Air Command and the RAF. The arithmetic is basic: thrustline offset x prop thrust = PPO moment.

For 12" offset and 600 lb. thrust, the moment is, of course, 600 foot-lb. The effect is precisely the same as attaching a torque wrench to the aircraft's CG and applying a 600 ft.-lb. torque in the nose-down direction.

The rotor's thrustline normally locates itself ahead of the CG by enough to "hold the nose up" and cancel this large nose-down moment. During a zero-G event (that is, an event in which the rotor temporarily assumes a zero-lift angle of attack), however, the rotor's thrust drops very close to zero, leaving nearly the entire 600 ft.-lb. of moment to flip the gyro forward.

To alleviate this problem, you can attempt to design a HS that produces a counter-torque of 600 ft.-lb. in the nose-up direction.

This turns out to be quite a challenge. The stock RAF tail tube gives the HS about a 7-ft. lever arm. 600/7 = 86 lb. The HS must be able to create somewhat more than 86 lb. of downlift without stalling.

A low-aspect ratio airfoil at its highest unstalled angle of attack makes 5-6 lb. of lift at 50 mph at sea level and 59 deg. OAT. (This figure comes from standard NACA airfoil tables, confirmed by tests I did on an instrumented sample HS). At that rate, to get your 86 lb. of down-lift, you'll need a HS of at least 14-15 square feet of area.

Even then, it won't offer full PPO protection below 50 mph. A RAF, like any other gyro, can fly slower than this and can encounter zero G at these slower speeds (though it's less likely than at higher speeds).

An airfoil's lift at any given angle of attack varies as the square of airspeed. The propwash of an RAF is over 100 mph (some friends and I measured it). Put the HS up in the propwash and at least part of it will gain power. You can't get the whole 16 sq. ft. in the wash, though, because the wash is too small. It's smaller in diameter than the prop itself by up to 50%. (Again, this figure comes from an actual test on a RAF.)

This is just some of the numerical work we've done over the years. A couple of people have done direct flight-stability tests, too, using stick locking and stick pulsing. Those test results have been posted here.

The FAA considers homebuilt aircraft to be "experimental." As such, the government does not have any responsibility for supervising the testing of these craft -- that's up to the builder. The kit seller is legally not the builder: the person who assembles the kit is. Legally, a box-stock RAF built by Joe Smith is a Smith gyroplane, not a RAF gyroplane. To the FAA, testing a "sample" RAF would be pointless.

[Harry_S.]

Tim O.

I wish I could pull and post partial quotes like you and others do, but, I don't know how so...


I chuckle and shake my head when I read some of the stuff you put in your posts eg...

Post #46,

"What makes you think you are better than"...

"Aint you listening"...

'You are a threat to yourself"...


Post #50,

"People like ***** are too blockheaded"...


Then YOU and others on the forum wonder why RAF drivers don't post their opinions?! You listenin'??

Sometimes I wonder how you address your students when they question something that you said, or, state their opinion?!


Cheers :)

[Chuck_Ellsworth]

Harry, how many RAF 2000 fatal accidents do you think were due to PPO?

[barnstorm2]

Sugar has not gotten us any farther then vinegar so far as I have seen Harry.

As stated by RAF drivers here many times before, they won't listen to anyone but there own (an from what I have seen not even their own if the opinion is counter to theirs..), so what does it matter what I say or how then?

The people that don't 'get it' won't get it no matter how I say it.

My post is for the benefit of those that know better to speak up and provide an example.

.

[LARRYEBOYER]

hey Animal. When you are close to the ground, the best technique for a good landing in an RAF is close your eyes ,pull back on the stick after closing the throttle.The landing may or may not be any better than the ones you are making now, but at least you won't see it.This technique has served me well for 27 years.

[C. Beaty]

Then YOU and others on the forum wonder why RAF drivers don't post their opinions?! Cheers :)

Some do, Harry.

To All Out There-The opinions of those that have no actual experience in a RAF are worthless to me--

Of course, Cierva’s opinions were also worthless since he didn’t learn to fly anything until nearly 10 years after he invented Autogiros.

[Gary_in_Orygun]

Gary,

...
well.. that kind of just leaves you..... without any RAF 'authority' figure as a role model for being smart, responsible and safe.

All of the 'official' RAF authority figures are either quiet on the issue or blatantly mis-inform.

...
You guys need to get vocal. RAFers for a safe stable RAF!

Every used RAF buyer that called me for advice ended up with a Horizontal Stabilizer on their machines. I can't claim that I was the determining factor, but I'll bet I had an influence. Instruction is the other big :whip: point I make rather strongly to potential gyro flyers who ask me for input.

I know I'm not a CFI or an RAF representative. But I can do my part. It does help that I have an RAF to give my voice just a hair more authority. We talk about the few CFIs that do not push or "strongly" endorse adding an H-stab to a stock RAF. But there are good CFIs out there that do make that claim and understand the issues of a high-thrustline. Paul Bruty and Ron Menzie both influenced my decision when I was in the market in early 2000.

I cannot disagree with the stock RAF'ers that state that training will keep them safe in most cases. But that means they better understand the high-thrustline issues and be extra diligent. High-time RAFers don't have to think about what they do, they just react. High speed and high engine RPMs are taking the stock RAF2000 close to a line I'm not willing to approach.

If a stock RAF'er says that the H-stab takes away required manuverablity, then we have a disagreement. And this I speak from 275 hours of experience in stab'ed RAF2000s. I have to admit that when the RAF moved to South Africa I had some disappointment that the Stabilator was still being touted as a stabilizer. All I can do is, with understanding and gentleness, state my opinion and facts as I know them when someone repeats the story told to them about the stabilator.

[barnstorm2]

Originally Posted by jvitable
To All Out There-The opinions of those that have no actual experience in a RAF are worthless to me--


Of course, Cierva’s opinions were also worthless since he didn’t learn to fly anything until nearly 10 years after he invented Autogiros.

Nice! I need to remember that Chuck.

Every used RAF buyer that called me for advice ended up with a Horizontal Stabilizer on their machines. I can't claim that I was the determining factor, but I'll bet I had an influence......

Thank you Gary.

If someone ever writes a RAF article for the http://gyrowiki.com I will add this post as a 'see also:'

.

[gyromike]

Hi Mike,
I know you directed your question at Tom, but I do know the answer.

The Xenon isn't getting around the 51% rule, it's certified through a different rule. A very incomlpete summary is that the Xenon gets its airworthiness certificate through the ELSA Conversion rule (that happens to expire this month). Xenon has requested an exception to the rule to continue after this month. Hopefully there will be an answer sometime soon!

Scott

Thanks Scott.
I remember reading that the Xenon folks were looking to get a waiver to do this, but I hadn't heard if it had been approved yet.

[Heron]

hmmm . . .class action lawsuit
Reckless endangerment of self
attempted manslaugther on passenger
(heck that grants a firearm display)
conspiracy to trespass
. . .maybe not! :)
Heron

[jvitable]

Joe,

I am glad you have the HStab, buy why? If you have installed the HStab you thus must have at least some understanding of the issue?

Closing the throttle is no answer. A PPO event takes only about 1 second to happen. Do you really think that by the time you 1. figure out what is going on and then 2. Take action that LESS THEN ONE SECOND HAS GONE BY?

What makes you think you are better and more skilled then the multi-thousand hour CFIs and other pilots that have been killed in PPOs?

Do you understand how the offset-gimble provides a LIMITED FELLING of stablity but does not actually make the RAF stable? If so please show us by explaining it here to us. You know your RAF you would know how it's componets work right?

There ARE people with RAF's recommending that no one fly the stock RAFs, arn't you listening?

I hope to God you are not taking up any passengers with that kind of attitude toward learning, safety and aerodynamics even if you do have an HStab.

With your attitude toward safety, learning and pilotage you are a threat to yourself, your passengers, this sport and anyone or thing you fly over.

-----

Jonathan,

Excellent post.

Jonathan--First-I never told anyone to fly anything!Thats something they can decide---Second-I tell you of my experiences and you call it attitude-Third-I never said pulling back the power would save you after entering PPO -Doug O conner-a friend of mine is the person who studied PPO and from a video of a PPO crash,he found the time from pushing the stick forward at full power to pushover is .6 seconds- I was trying to state that pulling the power back before this point will prevent PPO !!! and you know it--!!! Forth-I put the stab on because I might be wrong--something you never are--You being the know it all you are!! Joe 281-489-2019

[barnstorm2]

Joe,

1. I am not Jonathan.

2. Please read the very post you quoted....."by the time you 1. figure out what is going on and then....Take Action..."

If people had warning that they were entering a PPO we would not have so many high-time pilots dying from them.

3. I did not know anything about this topic until taught so by the members of Norms Forum and even then it took Ron Awad and Doug Smith to convince me. Maybe someday you will be just as lucky.

4. What about my questions?

What makes you better more skilled then the multi-thousand hour CFIs and other pilots that have been killed in PPOs?

If you will only listen to RAF pilots what about those that say the STOCK RAF's flaws do exist?

[automan1223]

I think the problem is in thinking that PPO is a smooth linear event. It is not .

That somehow you will feel it in the controls or attitude of the airframe and be able to reverse the tide of inertia before you go tumble.

The problem is that the forces are so great, because they are so far out of line, that there is no time to "grab" air and get the rotor working again, by the time you feel it, it is already to late.

In any event having flown just about every configuration I can tell you from first hand experience that a stock raf, or even one with a small HS, has a mind of its own. As a pilot you can learn to anticipate its antics and jab some corrections to keep it flying straight and level but It does not fly anything like a NCLT, or CLT gyro.

I like my shopping cart analogy, but I think I have a better one, here below.

Next time your driving and go skidding off the road during a hydroplaning or snow / ice event, tell me how despite your best efforts you will regain control once you have lost traction with the road. ? All you can do is go along for the ride, you are at the mercy of the weight and balance of your auto. And around you go !

Once your rotor has lost "traction" with the air, it is at the mercy of the prop thrust line, and the c.o.g.

And around you go !

Jonathan

[barnstorm2]

True or False??

Can some one answer this question for me?

Is it TRUE that a gyroplane with a very high offset (like 10 inches) and a short coupling (as in a SxS gyroplane vrs tandem ) will tend to PPO 'quicker' IOW with less 'warning' then a HTL gyroplane with a lesser off-set thrust line?

I thought I had seen something to this affect posted once but I can't seem to find reference to it.

Can someone tell me if this is true or false?

.

[Doug Riley]

Tim, the physics of angular acceleration (i.e. the beginning of a spinning motion) are not essentially different from the physics of straight-line acceleration.

In both cases, the variables are the size of accelerating force, time and the mass of the thing being accelerated.

The larger the force applied to a given mass, the faster the acceleration.

The larger the mass for a given force, the slower the acceleration.

The tricky bit with angular (as opposed to straight-line) acceleration is that a radius plays a part in quantifying the effects of both the mass and the force.

For a given mass, the farther away from the center of rotation (CG) the mass is concentrated, the greater its rotational inertia and the slower it spins up. A tandem gyro has more rotational inertia than a SxS of the same weight. The effect is the same as placing exercise weights -- first on a short dumbbell bar and then on a long barbell bar, and trying to rotate the bar end-over-end. It's easier to spin the short bar. It takes less time to get the short bar up to a given rotational speed.

It's also easier to STOP the short bar. A tandem gyro will require more force and/or time to stop a PPO once it has begun.

Radius also affects the effectiveness of the force in creating the spin. If the force (prop thrust) is applied close to center of rotation (CG), it has little leverage. IOW, its moment is small. If the force is applied farther from the center, it has a greater moment. The greater moment will spin a given gyro faster and will get it spinning at Rate X in less time.

Physics buffs will recognize that I've been a little fuzzy with definitions here, to avoid too much techno-jargon. Look up the concepts of "moment of inertia," "couple," "moment" and "impulse" if you want the full Monty.

[Doug Riley]

Joe, fly what you like, but, for your own well-being, do NOT believe that PPO can only be set off by pushing the stick full forward at high speed. Bensen circulated that lie in order to blame the victims of his machines for a basic flaw in the machines themselves (which has since been corrected in most gyros on the market).

A partial loss of rotor thrust is enough to set off the self-energizing action that occurs in a PPO. Climbout (when you're not going very fast but have the engine firewalled) is a common time for a PPO. It would be odd to toss the stick full forward when trying to climb out.

The partial loss of rotor thrust can and will occur upon any reduction of rotor angle of attack (AOA). Thrust is roughly proportional to AOA. Cut your rotor AOA in half and rotor thrust is immediately halved, too.

A downdraft, WITH NO MOTION OF THE STICK AT ALL, will instantly reduce your rotor's angle of attack. If your rotor flies at a 10-degree AOA at 60 mph, then an abrupt downdraft of 930 feet/minute will put you into zero G with NO action on your part. This will start the PPO process unless you are very quick on the throttle and let the stick float back.

[barnstorm2]

Joe,

I agree, poor Jonathan got the worst of it. ;)

Not all STOCK RAF crashes are PPO but many of them are. If they have the symptoms of a PPO such as a loud pop then tumbling out of the air, rotorblades bent in a cone, a chopped off tail and or pieces of the prop or rudder separated in flight than it is VERY likely a PPO.

I am not sure what your expertize is in anazlying gyroplane wreaks but almost all of them have been discussed here or on Norms forum. If you have some understanding that the folks here do not, then for the good of all, I think you should share that knowledge. You may also want to contact Jim Mayfield about joining the response team.

Doug Riley has already posted about how it is very possible to get into a PPO in normal weather, with no warning.

And yes, you are absolutely correct, THAT IS A BIG PROBLEM. And that is why the gyroplane community is so tired of these completely PREVENTABLE deaths and the few remaining pilots that still repeat mis-information about PPOs.

Let me know if you ever come across a good bathtub, I have drawings for the rest of the pluming. ;) Mine even has a massaging 2-per-rev shower/rotor-head.

.

[barnstorm2]

Tim, the physics of angular acceleration ....

Shall I take that as TRUE is the correct answer?

.

[Doug Riley]

Tim: Kind of.

For a given all-up weight, thrust and thrustline position, the SxS will accelerate quicker into the PPO.

Again holding everything else constant, the higher the thrustline, the quicker the acceleration into PPO.

BUT, while the tandem takes a split second longer to get rotating, once it IS rotating at a given rate, it takes more force and/or time to stop. As the gyro pitches forward, rotor thrust is being lost -- that is, the available force to stop the pitching is disappearing fast. Especially with the tandem, if you don't catch it early, you won't be able to catch it at all.

Of course, it's insane to be playing this kind of deadly game and making distinctions based on how many fractions of a second you have to save your life. An adequate HS and thrustline location make this whole exercise unnecessary.

[Ron Marlett]

Joe, fly what you like, but, for your own well-being, do NOT believe that PPO can only be set off by pushing the stick full forward at high speed. Bensen circulated that lie in order to blame the victims of his machines for a basic flaw in the machines themselves (which has since been corrected in most gyros on the market).

A partial loss of rotor thrust is enough to set off the self-energizing action that occurs in a PPO. Climbout (when you're not going very fast but have the engine firewalled) is a common time for a PPO. It would be odd to toss the stick full forward when trying to climb out.

The partial loss of rotor thrust can and will occur upon any reduction of rotor angle of attack (AOA). Thrust is roughly proportional to AOA. Cut your rotor AOA in half and rotor thrust is immediately halved, too.

A downdraft, WITH NO MOTION OF THE STICK AT ALL, will instantly reduce your rotor's angle of attack. If your rotor flies at a 10-degree AOA at 60 mph, then an abrupt downdraft of 930 feet/minute will put you into zero G with NO action on your part. This will start the PPO process unless you are very quick on the throttle and let the stick float back.

That sounds like a full power cruise climbout on a clear sunny day with gusty/thermal conditions.

The vital fact lost on some who do not fully understand where the control forces they reley on come from, is that as you approach zero G, the rotors stop generating lift. The application of cyclic pitch changes throughout the rotor rotation, changes the angle of attack of the blades as they pass around the circle and modulate the ammount of lift they create around the rotor arc. This change in lift causes the rotor disc to change angle and the rotors overall thrust vector to move in relation to the aircraft's CG, This change in thrust vector to CG in turn rotates the airframe in pitch and roll. Without lift from the rotor blades, there is no force to power the cyclic change(and also no force to power autorotation so the blades decelerate) so you get no disk/thrust vector change. Your stick is no longer commanding the rotor disk.

With no control authority to help arrest your forward rotation once it has begun, when you do regain rotor loading, it will be in a negative direction and the nose pointed way downhill at that point. This rapidly increasing nose down pitch attitude drives the tail and prop up into the decelerating and coned down rotorblades, but you are already way past the point of no return long before this happens. I would liken this to tripping with your hands tied behind your back. You didn't intend to trip, and you didn't know you were going to trip UNTILL it happened. At that point with your hands tied behind your back, it is too late and the only thing that is going to stop you is the ground...

[jvitable]

Joe,

I agree, poor Jonathan got the worst of it. ;)

Not all STOCK RAF crashes are PPO but many of them are. If they have the symptoms of a PPO such as a loud pop then tumbling out of the air, rotorblades bent in a cone, a chopped off tail and or pieces of the prop or rudder separated in flight than it is VERY likely a PPO.

I am not sure what your expertize is in anazlying gyroplane wreaks but almost all of them have been discussed here or on Norms forum. If you have some understanding that the folks here do not, then for the good of all, I think you should share that knowledge. You may also want to contact Jim Mayfield about joining the response team.

Doug Riley has already posted about how it is very possible to get into a PPO in normal weather, with no warning.

And yes, you are absolutely correct, THAT IS A BIG PROBLEM. And that is why the gyroplane community is so tired of these completely PREVENTABLE deaths and the few remaining pilots that still repeat mis-information about PPOs.

Let me know if you ever come across a good bathtub, I have drawings for the rest of the pluming. ;) Mine even has a massaging 2-per-rev shower/rotor-head.

.

Tim-you are being a jerk!!!You type better than you read!-told you before I am expressing only my personal experiences-which have been good concerning RAF.I know many ways to have a PPO!!!And I would think most (mistakes) crashs would end in PPO!I have flown in a RAF/Sparrow Hawk and would give up gyros rather than fly that School Bus around-Now I am Only Talking about my experience with this one machine--One more thing--owned one of the largest Hobby Centers in the US for 18 years.In that time I taught 100,s of people to fly RC!You never know who will freeze at the controls--And I mean FREEZE---I not only would never allow a passenger to touch the controls-I would remove the right stick!!(never understood how instructers take such a chance)You are right about beginners and RAF,s or any other high powered machines-but their were very few of my new customers that wanted to start their training with a ugly trainer-they wanted to start with a Pitts(ect)---needless to decribe the result---I think you are trying to save all of us and I appreciate that but you are beating a dead horse-You have made your point-I doubt any newby out there will ever fly a gyro.I fought off all the negative crap from the fixed wing community-If I had seen this forum also-I would have stayed with fixed wing only.I will make you and your group happy and say UNCLE-RAF,S in stock form are killers/with stab also--maybe now I can pick up a second machine cheap and save a life to boot!! Would love to have you educate me by phone--GYROCIDE JOE 281-489-2019 PS-The only reason I have time for this crap is my knee is out and I am stuck at home (and no-- my RAF didn"t kick me)-----also this popping sound we hear so much about--I had an engine out and it caused a very loud popping sound-maybe a backfire or ?After hearing from you guys about (A popping sound before PPO)- you can bet I needed a new pair of shorts-I will SEND you the bILL TIM---thanks for keeping me entertained while I have been stuck in the house......

[RockyMeLad]

I would liken this to tripping with your hands tied behind your back. You didn't intend to trip, and you didn't know you were going to trip UNTILL it happened. At that point with your hands tied behind your back, it is too late and the only thing that is going to stop you is the ground...

Ron,
At first glance it seemed like an apples/oranges comparison (which I suspect most stock RAF advocates would point out), but after some reflection. . .
more truth than fiction based on the physics of the situation.

Someone that can walk reasonably well with hands tied behind the back, could walk for years without problem. Even on rough ground and some "stumbles" adequate balance and muscle response could prevent disaster.
Until the unexpected or a too serious stumble and. . .
"gravity works". :rip:

[Chuck_Ellsworth]

GYROCIDE JOE

What is a gyrocide?

[Walter]

A downdraft, WITH NO MOTION OF THE STICK AT ALL, will instantly reduce your rotor's angle of attack. If your rotor flies at a 10-degree AOA at 60 mph, then an abrupt downdraft of 930 feet/minute will put you into zero G with NO action on your part. This will start the PPO process unless you are very quick on the throttle and let the stick float back.

So what should a pilot of a reasonable stable gyro DO when he/she feels a sudden reduction of g-force (or what other sign is typical of initial PPO?)? Immediate reduction of throttle? How much? What about the stick? What does "let the stick float back" mean? Some practical hints would be of great help.

Thanks

Walter

[birdy]

Walter, if its of any comfort, iv hit thousands of them.
In both machines, in vairying degrees of stability configurations, sum just make you a little light in the guts, sum try to force your guts out your mouth, sum are sudden short ones, others will leave you in suspension, but im still alive. :)
Just remember, dont choke it and if its real rough, lower your airspeed to a slow cruise if your wurried. [ the harder/faster you hit the bump, the worse it feels, just like a car]

[Heron]

It should be GYROCIDAL, Chuck.
Meaning a maniac suicidal RAF Stock non believer (I guess if it is suicidal then he belives)
So . . .feeling light on the seat at low to moderate rrpm when downdraft appears and you hear . . bang . . .Bang in rapid succession (blades hiting the tail) you shop throttle a bit too late and pull stick back (it could have happened already when going light which helped the bang go on) . . .kinda explains the half second where it takes place?
I mean, could it be that the blades getting soft will the strikes be the major event in getting all irrecoverable?
thanks
Heron

[gyromike]

So what should a pilot of a reasonable stable gyro DO when he/she feels a sudden reduction of g-force (or what other sign is typical of initial PPO?)? Immediate reduction of throttle? How much? What about the stick? What does "let the stick float back" mean? Some practical hints would be of great help.

Thanks
Walter
Walter,

If the aircraft has positive static and dynamic stability, you don't have to do anything. It will react to the winds in a stable manner, always trying to weathervane into the relative wind.
No throttle chops.
No sudden aft stick.
No need to 'float the stick'.

'Floating the stick' refers to using a loose grip on the stick, perhaps encircling the grip with the fingers but barely touching the grip. This allows the offset gimbal head to react to g-loads using the trim spring resistance.

Gorilla-gripping the stick negates the effect of the offset gimbal.

[gyromike]

GYROCIDE JOE

What is a gyrocide?

It's what happens if someone touches the stick on his RAF, I guess. :noidea:

One more thing--owned one of the largest Hobby Centers in the US for 18 years.In that time I taught 100,s of people to fly RC!You never know who will freeze at the controls--And I mean FREEZE---I not only would never allow a passenger to touch the controls-I would remove the right stick!!(never understood how instructers take such a chance)

[Doug Riley]

I once almost committed gyrocide. I was 18, and was so mad at my cantankerous VW-Bensen that I had a sledgehammer in my hands, ready to reduce the thing to scrap. Somehow, I got a grip and walked away to cool off. The impetuousness of youth.

Walter, what the others have said is correct. If a gyro is pitch-stable, it will fly through zero G with no correction needed. The nose will pitch up on its own to restore AOA. IOW, it's a non-event. No throttle-chop, no stick float, no ruined undershorts.

[animal]

Joe,


Mine even has a massaging 2-per-rev shower/rotor-head.

.

Is that what it's called when you get cought in the Rain?...lol

[barnstorm2]

I can also come up with many reasons for these crashs other than PPO.--call me and I will explain each one to you! If PPO happens in normal flite in normal weather with no warning then we have a big problem.

Joe, If you have reason to believe that one or more of the PPO fatalities were caused by something other then PPO you should share that information with all of us. The reason we discuss these accidents is to prevent future ones.

If you are going around telling other pilots that these accidents are not PPOs and you do not have the physics/aeronautical background to analyze these wreaks and have not submitted your ideas for peer review then you are doing a great dis-service to our community.

One of the few positive things that can come out of a crash is the ability of other pilots to learn from it and avoid the same mistakes.

As already stated, though uncommon, PPOs can and do happen without warning, and yes that is a big problem.

I know many ways to have a PPO!!!And I would think most (mistakes) crashs would end in PPO!

I think that varies greatly, and mistakes certainly don't have to take your life.

I have flown in a RAF/Sparrow Hawk and would give up gyros rather than fly that School Bus around-

This is a common misconception and one that has done much damage I fear.

There is NO reasonable performance benefit to having an unstable gyroplane. Moving your thrust-line closer to your CG or all the way to your CG (CLT) does nothing to reduce your performance. In fact having a gyro that can not PPO increases your safe flight envelope tremendously.

I think you are trying to save all of us and I appreciate that but you are beating a dead horse-You have made your point-I doubt any newby out there will ever fly a gyro.I fought off all the negative crap from the fixed wing community-If I had seen this forum also-I would have stayed with fixed wing only.


Joe, I doubt a few threads of people heatedly debating simple physics on an internet forum can come close in anyway to hampering our sport compared to CNN headline news running video footage every hour of a dead high-time pilot and child that were flying on a clear sunny day.

I am quite tired of people and other aviators calling gyroplanes "death traps" and the like. These people have never visited an internet forum, they get this opinion from our horrendously terrible safety record.

Our safety record is what hampers our sport. Our safety record would be as good or better then the rest of the sport aviation community if we could reduce PPO fatalities to near zero.

Now that there are no longer any gyroplane kit manufacturers producing unstable gyroplanes we can hope things will start to get better, and they have. That leaves the large supply of unstable legacy gyroplanes still at large. If we can educate the owners, sellers, buyers and re-builders of these legacy machines about the facts of stability and PPO we can safe many lives and our sport.

Denying what we know about PPOs, spreading false information about stability, performance, the cause of gyroplane fatalities from PPOs and related mis-information hinders this process and indirectly costs lives.

[Ron Marlett]

So what should a pilot of a reasonable stable gyro DO when he/she feels a sudden reduction of g-force (or what other sign is typical of initial PPO?)? Immediate reduction of throttle? How much? What about the stick? What does "let the stick float back" mean? Some practical hints would be of great help.

Thanks

Walter


Walter
Since it wasn't mentioned, and I don't know if you know this or not, but a stable gyro will have the normal inflight rotor thrust line passing just slightly BEHIND the aircrafts center of gravity. It is running behind the CG because the combination of prop thrust, horizontal stab and airframe drag forces inflight are trying to rotate the aircraft nose up, and the rotor thrust line passes behind the CG to counter this force and keep the aircraft in level powered flight. In this scenario, flying into a downdraft and a low-G situation reduces the ammount of rotor thrust. With this reduction in rotor thrust, the other forces acting on the airframe pitch the nose up and help to re-load the rotor system. Flying into an updraft increases the rotor thrust and pitches the nose down into the updraft and helps maintain altitude without ballooning as bad. Even if you have a death grip on the stick, the airframe will still want to rotate in a desireable direction. As mentioned a pilot of a reasonably stable gyro, just like the pilot of a reasonably stable fixed wing, shouldn't have to do much at all except re-point the aircraft in the desired direction if it has wandered from the desired path, after the event has passed.

In the case of the stock, high thrustline RAF or any other gyro in this configuration, the thrust and aerodynamic forces acting on the airframe in powered level flight are trying to pitch the aircraft nose down. The only thing keeping this from happening and maintaiing level flight is the rotor thrust vector passing out in front of the aircraft CG. In this type aircraft a low-G event reduces the force holding the nose up in level flight and allows the thrust and drag forces to rotate the aircraft nose down, further unloading the rotor system. If you have a deathgrip on the stick, the rotor system sees this airframe rotation as a stick forward command. If you are floating the stick, the stick will move to the rear as the airframe rotates forward and not as much of the command will be transmitted to the rotorsystem.

In the case of 600 pounds of engine thrust 1 foot above the CG you have 600 FT/LB of torque trying to rotate the nose down at fullpower. This coupled with the heavy weight moments in a 2 place side by side configuration, clustered close around the aircraft CG(see Doug's explanation of moments of inertia above) leaves you with an airframe capable of a very fast nose down pitch acceleration if you remove the rotor thrust. Ever play on a teeter-totter as a kid? Ever jump off the seat at the bottom and leave your totter partner to freefall to the ground. That is what happens when you radically alter the forces applied to a system whos attitude is derived solely from the forces being in balance.

I think an aircraft that had a extremely low thrustline of say -12" would also be very uncomfortable to fly. Heavy down drafts or rapid power increases would try to stand the airframe on it's tail. Conversly, a rapid power reduction at full speed coupled with the low slung drag typical of a gyro could be very dangerous and unload the rotor into a drag-over scenario very similar to a PPO.

[Ron Marlett]

This is a common misconception and one that has done much damage I fear.

There is NO reasonable performance benefit to having an unstable gyroplane. Moving your thrust-line closer to your CG or all the way to your CG (CLT) does nothing to reduce your performance. In fact having a gyro that can not PPO increases your safe flight envelope tremendously.


It is also tremendously more efficient, which will increase the speed and climb performance of the gyro. If you have a high thrust line gyro that is developing 600 FT/LB of nose down airframe torque at full power, the power to counter this force and maintain level flight is comming from somewhere. Either in the form of a monster horizontal stab with a huge nose down angle making a bunch of negative or downward force at the tail and it's associated drag, or it is comming in the form of increased rotor thrust. This thrust or lift from the rotor system and it's associated drag is in ADDITION to that already being generated to lift the aircraft off the ground. IE: if you didn't have to counter 600FT/LB of nose down torque, you wouldn't need this additional force and it's associated drag which hinders overall aircraft performance. It would be the same if you had 600FT/LB of nose up torque which you had to counter to maintain level flight. VERY INEFFICIENT!

[Passin' Thru]

Ron, that was a very good response to Walters' inquirey.:first:

[Doug Riley]

Ron, one nit-pick about the physics. Putting the rotor thrustline forward of the CG to hold the nose up doesn't increase the workload of the rotor. You take the same ol' amount of rotor thrust and simply re-locate it. It's the same as moving X pounds of weight aft -- neither one requires any additional work or energy in flight.

A downloaded tail DOES consume some energy via trim drag. That's one more reason to move the prop thrustline to a CLT position -- CLT is more efficient than HTL with fully downloaded stab. Eighty pounds of HS down-load looks just like eighty pounds of lead to the rotor.

[barnstorm2]

Doug,

Wouldn't a 'human stabiliser' be much less efficient then a stable gyro?

What I am asking is this.

A human stabilizing an unstable gyro uses what? The cyclic.

When you move the cyclic you draw power out of the disk vs a rotor disk that is allowed to hold position.

A stable gyro requires no (or less) pilot workload/input and thus does the rotor disk loose less energy?

.

[Doug Riley]

Yes, tipping the rotor here and there to stay upright uses up rotor energy. This energy has to be replaced by the engine.

If you could somehow tip the rotor directly using your own muscle power, you'd get tired in a hurry. It's surprisingly hard to alter the orbit of a bike wheel held by its axle; imagine trying to move a 30-foot, 100 pound version doing 300-plus RPM.

To be fair, though, the micro-corrections made by a seasoned RAF pilot (or by the gimbal head) probably don't cause a signficant loss of rotor energy. Serious "chasing" of the machine by a low-timer is another matter.

Smooth flying is more efficient -- just like smooth driving, and for the same reason.

[barnstorm2]

Thank you Doug!

[Heron]

Man! All this workload talk and the heath down here is getting me tired!
Hey Joe, get your knee back where it belongs and have a cold one!
That is what I am going to do now!
Someone please tell me the flying differences RAF X SH?
School Bus? C´mon . . .
Heron

[gyromike]

Stupid comment for a Forum Administrator to make-this is what is causing the ECOCIDE of this Forum !(knee still out) Joe 281-489-2019

ECOCIDE?

Did I just kill an ecology?

[barnstorm2]

Joe,

I am sorry that I have to be the one to bear the bad news to you about stability and it's effect on HTL gyroplanes and the resulting deaths we have suffered because of it.

I am just the messenger. I don't have anything against STABLE RAFs I would love to have and fly one.

You can take out all of your frustrations on me, that is fine. I have a thick skin and I can take it.

If training could solve the high thrust line / stability problem then a lot of CFIs and high time pilots would still be alive today. That simply does not work and it is not working.

The solution is to simply mitigate the FLAW in the design. Period.

You can lash out all you want but each of your rationalisations of owner pride have all been addressed.

You have installed an HStab on your machine right? So at least some part of you must understand the issue here.

I am not out to 'bash' you or your machine. If I did you would certainly be able to tell the difference.

It's simple high school physics. There are some good videos that are free, online and can teach you everything you need to know about the subject.

How do you inform someone that his fiancée, the love of his life, has gonorrhea without causing mental anguish; especially when his first reaction might be to shoot the messenger?

I know what you mean CB. But at least doctors are well paid to do this stuff....

.

[C. Beaty]

Tim, don’t you know that proselytizing the RAF True Believers is an exercise in futility?

Your chance of producing a proselyte is about the same as that of a Mormon missionary in Saudi Arabia, although you may not get your head chopped off for trying.

[barnstorm2]

Is that what it's called when you get cought in the Rain?...lol

Shhh!!

That's how I get my monthly shower, but I am not IFR rated yet!

Tim, don’t you know that proselytizing the RAF True Believers is an exercise in futility?

Your chance of producing a proselyte is about the same as that of a Mormon missionary in Saudi Arabia, although you may not get your head chopped off for trying.

Yeah, I know. I did note the key words "may not".

I hope that it does some good for the poor lurkers who hear these excuses from the TB's.

.

[Ron Marlett]

Ron, one nit-pick about the physics. Putting the rotor thrustline forward of the CG to hold the nose up doesn't increase the workload of the rotor. You take the same ol' amount of rotor thrust and simply re-locate it. It's the same as moving X pounds of weight aft -- neither one requires any additional work or energy in flight.


I'm sorry Doug, I graduated from the "There is NO free lunch" school. It has to cost something to counter that ammount of torque? That is lift that is not pointed in direct opposition to the force of gravity to lift the craft. You must have to make more to counter this additional nose down force than you would in an identical weight/HP aircraft with CLT and no nose down torque force to counter. Just like it takes more lift out of a fixed wing to maintain level flight in a turn than it does in straight and level flight. The re-directed lift from the banked wing that is pulling the aircraft around the turn is no longer directly opposing gravity like it was in level flight... So you must either trade airspeed or add power to compensate and maintain altitude.

[birdy]

Walter.
In case your getn abit confused by all the responces to your quiery;
So what should a pilot of a reasonable stable gyro DO when he/she feels a sudden reduction of g-force
Ill just clear one point.
You asked about wot to do in a reasonable stable gyro.
Everyone had correct answers for a stable one, not a reasonably stable one, and i dout most responders would know wot you fly. They either assumed you have a stable one, or told you the hows of a stable one, but said nuthn but one that is not dynamicaly stable.

[scott heger]

RAF bashing seems to be a regular sport on this forum, and I play in the game also. The right to fly whatever the hell you want is the most important freedom to protect. Any pilot that chooses this model ,knowing the history and hazards involved; takes on his own risk, and I have no problem with that.

The biggest problem is to the uniformed passenger who may climb into the passenger seat thinking they are flying in a FAA licensed aircraft. If they are getting into a stock RAF on a windy day, they are at much greater risk then they may realize. The second group is the potential/new RAF buyer, soon to be newbie gyro pilot who does not know the sad history or realize the stability problems others have encountered. Those are the ones we need to get the message out to.

RAF are good looking machines that sell sizzle before safety. They can be flown forever by a well trained pilot if flown within speed and wind limitations. The problem is this envelope is much lower than on many other gyros available. All the RAF'S I have ever seen flown are in low wind conditions and basically straight and level with low bank turns. These guys are still around because they fly within this safe flight envelope.

My SportCopter is not limited in this manner 35 MPH takeoff winds, no problem. 90 degree banking turns, bring them on. High wind gust while flying, the gyro remains pitch stable, and just floats up or down. Ah, but you say, thats a single place, its not the same. Well the SportCopter two place trainer is much bigger and almost as capable. It will bank and turn like no RAF I have ever watched. I have put this two place into induced flat 360 spins with 10 rotations. The point is you don't have to want to fly like this , but gyros with wide performance and safety margains mean you don't have to settle for less than a stable machine. Modified RAF's and Sparrowhawk conversions are available to enhance this flight envelope and safe flight. It is the owners choice to take advantage of these mods or not. If you fly a RAF gyro,I don't think you deserved to be bashed at all, just damn careful about choosing your flying conditions, if you don't want to join the NTSB list.

Scott Heger, Laguna Niguel,Ca N86SH

[PW_Plack]

Guys,

Kerry makes a rational, well-written case for the idea that the tone of the debate drives away the very people who need exposure to it, and the thread turns into just another 100-rant pissing match. You guys do understand that you've demonstrated his point, right? This gets like debating abortion after a while. You lose the debate when your emotions invade your writing, whether your opinions are factual or not.

PTKay says... Why FAA cannot learn from CAA ???
Every government agency, anywhere, suffers from the syndrome called, "not invented here" to some extent. FAA included.

Don't you think the factory LSA will clean the market.
There are no factory-built LSA gyros in our country, except for a handful of Xenons. I hope Xenon, GBA and Sport Copter achieve this breakthrough. All have expressed the intent.

Chuck Ellsworth says...
prop·a·gan·da –noun
1. information, ideas, or rumors deliberately spread widely to help or harm a person, group, movement, institution, nation, etc...
Kerry, what makes you accuse some of us of the above, do you deny physics?

Chuck, where in your definition of "propaganda" does it limit propaganda to lies? If you're pointing out truthful "information or ideas" with the intent to discredit a "group or institution," which you clearly are, the truth still qualifies as propaganda. How is it denying physics to call you on it?

C. Beaty says...
Rusty Nance, the current president and Greg Gremminger, the current vice president, are both knowledgeable about gyroplane theory and are well aware of the deficiencies of the RAF.

Forum content at Mentone '07, and the use of a graphic of an unstabbed RAF to promote the convention on the website last summer, suggest the organization still struggles with consensus on the issue of stability-vs-training as the answer to PPO prevention. I'm not being critical of any individual here, just noting that there's a lot of inertia to "conventional wisdom." The debate obviously continues throughout the sport, and within PRA, not just here on the forum.

Stats, real ones, rates, with hours-flown as the denominator, would be a huge step toward resolving this.

jvitable says...
The opinions of those that have no actual experience in a RAF are worthless to me...

Joe, is Russian Roulette dangerous? How much actual experience do you have playing Russian Roulette?

[Walter]

Thanks, Birdy, for addressing the issue.
Clearly, in a stable situation you just sit back. But if the rotor gets unloaded, e.g., by a local gust that affects the HS differently from the rotor, or passenger input (just constructing a scenario), what would you recommend to do?
What do you do? Hints from you experienced guys would help a lot!
Thanks,
Walter

[Heron]

I would not try to guess what someone I don´t know will do or not.
This Forum has a pretty dense and rich core of techno stuff for the advanced and a large (largest?) audience interchange in the gyro arena.
Right now Vance is telling us, day-by-day and step-by-step his adventures (thanks Vance) also this new accident involving a RAF gave us more fuel for the bonfire where the last doubts about instable designs will be burnt.
Of course in any association of humans (maybe animals too) all kinds of interaction will happen and some are pretty nasty, not our case mind you . . .
If someone has a twitchy nose or weak stomach, there are remedies, one of them it is called patience . . .you will learn and start to enjoy the experience even make friends here.
So don´t blame me that still here trying to equalize and belong, the missing part is you . . .the walk way too early types.
You are welcome here and stay enough to understand the true spirit of our Forum.
thanks
Heron

[Hognose]

We have no idea of how many gyros are currently flying in the USA, we also don't have a clue as to how many hours they fly. Gyroplane pilot's have long been the leaders in illegal flying, probably only recently surpassed by powered parachute owners.

Hi Tom

It is with reluctance that I post in this thread. But Tom makes an absolutely key point here.

Our data are nearly worthless. We have no earthly clue how many gyros are flying. Even manufacturers usually don't know who owns their high-time ship and how it's doing, unless they're fortunate or diligent enough to keep a machine out ahead of their customers (elsewhere in the forum, Dennis Fetters has explained why this is good, in part of his explanation why he doesn't want people taking the risk of buying and flying his old Mini-500s with the factory long gone).

The British, by comparison, collect an annual census of hours on "Permit to Fly" machines. In the UK this is anything that doesn't have a regular Normal, Aerobatic, Utility or Transport Certificate of Airworthiness. This group includes homebuilts and gyroplanes among other machines. Their Permits must be renewed annually and the hours must be recorded (on the honor system, to be sure) when that is done. Since the Permit costs money, scrapped machines drop off the registry tout de suite.

A fair guess is that the RAF probably leads in both sales and hours flown. They probably also lead in fatalities. This would not trigger an FAA alarm.

Without some sign that rates, not numbers, were out of line, FAA will not act. And with no accounting for hours flown, no accurate rates are possible.

The FAA knows more about us and our problems than you imagine. My biggest fear is that they might get involved.

Yep. Imagine you are a bureaucrat at 800 Independence. Imagine the Director (a political appointee hashed out between the President and Congress, so the last two directors were career bureaucrats who knew enough about aviation to not need a stewardess's seatbelt presentation -- barely) comes to you and says, "we have had 20 fatalities in homebuilt gyroplanes in the last four or five years. I want to see a plan to bring that number to zero by 2010."

Remember you are a bureaucrat. You may not know even as much about flying as the administrator. You're probably a lawyer who couldn't make it in private practice and came last in your class from such a crummy law school you couldn't get a gig a public defender. You didn't take a job in Government because you wanted to work hard and make a name for yourself. How do you stop people from killing themselves in gyroplanes?

Remember how government action solved the drunk driving problem in 1919? Government is by its very nature a blunt instrument. It responds to crises and slogans, not to science.

cheers

-=K=-

[Doug Riley]

Ron Marlett, I'll continue our discussion of the physics of HTL on a separate new thread under the "aeodynamics" heading -- so we don't de-rail this thread.

[birdy]

What do you do? Hints from you experienced guys would help a lot!

Walt, mate, i cant tell you anythn coz i have no idea wot your flyn.
As you can read on every page on this forum, there are gyros and there are gyros, and sum need attention and sum dont.
I could say xyz, but xyz only applies to a certain configuration, and if your not flyn the right one, id be missinforming you. ;)

[PW_Plack]

Hognose said...

Without some sign that rates, not numbers, were out of line, FAA will not act...

Note that the FAA deals in rates only for commercial aviation. In general aviation, FAA publishes statistics for general aviation which list only accidents or numbers of fatalities per year, and claims safety improvements when those numbers drop, even when hours flown also drop.

The best guess available on a general aviation accident rate is based on use of fuel sales to estimate increases or decreases in hours flown, which is still a pretty rough guess.

Cynics believe the FAA doesn't want to know the real accident rate for general aviation, because Congress would be on its back to do something about it.

What would happen if the FAA could accurately calculate the gyroplane accident and fatality rates? (Be careful what you wish for!)

[Heron]

What would happen if the FAA could accurately calculate the gyroplane accident and fatality rates?
A better grip on reality? Maybe?
Heron

[PW_Plack]

Heron, that's the point...once gripping that reality, FAA would be compelled to act. We probably wouldn't like the result.

[Heron]

So it is up to us, the community Forum and PRA to create conditions that will not grant a FAA probe and possible ban?
We are doing a poor job, not enough tools and resolv to stop the nonsense.
I can tell you Paul, it has gotten better, way better with the new machines and people that joined after I did.
But this is the crossroad, our crossroad . . .what´s gonna be?
Enough slepping on it!
Heron (getting real)

[pwendell]

Peter,
When it comes to the FAA, stability IS an option.



Tom, the quote is, "Stability is not an 'opinion'", not , "Stability is not an 'option'", which I take to mean that stability in an aircraft is clearly defined and can always be measured (that's one of the things real test pilots do), and is not affected by our verbal arguments or perceptions at all.

I used to make the same error reading Jim's quote.