What is it about Gyros, and is there anything we can do about it?

BEN S

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Me and my friends have flown for years without an rpm gauge. I have one now. Sure I glance at it, but its not like I can't take off without it.
Here's a perfect analogy from another world.
You want to teach your young son/daughter how to shoot a rifle accurately. Do you teach them on open sights, or go straight to a red dot? Or a scope?
If you teach them sight alignment and trigger squeeze while focusing on the target, the front sight and the rear sight you will give them the building blocks to be the best they can be.
If you give them a red dot or scope to start on, the scope compresses all three planes into one (a scopes true benefit, not magnification) then they can become accurate with a dot or scope, then let them try an open sighted gun, they will not be as good. period. they have not mastered the basics and fundamentals.
Spinning up and taking off whether by hand or not without a rotor gauge is the best way in my opinion to learn the "feel" of a rotor that is spinning up to fly. Watching a gauge and reading off numbers that the gauge should be showing is not "learning to fly" it is learning to run a piece of machinery.
When things are not exactly the same as expected, will they adjust? Accident rate says "sometimes"
 

Vance

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To have a gyroplane pilot certificate In the USA if the check ride is done correctly the applicant has to explain about rotor aerodynamics and the proper takeoff technique. The applicant has to demonstrate several safe pre-rotations and takeoffs.

I called a client after a blade sailing incident that damaged his aircraft and he admitted he had let the tower hurry his takeoff and he had not built up slowly to the wind velocity and gust intensity as I had advised him. He had flown with three flight instructors and taken his check ride with a well respected DPE. I had covered both of these things at length with him and he recalled our discussions. He has more than 18,000 hour as pilot in command.

Most of the people I have talked to who had a blade sailing incident knew how to pre-rotate and take off correctly.

For some reasons (usually more than one) they did not follow procedure.

In my opinion there is no magic bullet that will prevent blade sailing incidents.

The takeoff procedure in a gyroplane may be task intensive relative to an airplane; in my opinion it does not require much skill.
 

Tyger

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Here's a perfect analogy from another world.
You want to teach your young son/daughter how to shoot a rifle accurately. Do you teach them on open sights, or go straight to a red dot? Or a scope?
If you teach them sight alignment and trigger squeeze while focusing on the target, the front sight and the rear sight you will give them the building blocks to be the best they can be.
If you give them a red dot or scope to start on, the scope compresses all three planes into one (a scopes true benefit, not magnification) then they can become accurate with a dot or scope, then let them try an open sighted gun, they will not be as good. period. they have not mastered the basics and fundamentals.
If you teach your kid to drive using an automatic transmission, they will not drive as well when they have to use a stick-shift manual.
But is that a "when", or an "if"?
(My son drives a manual, incidentally).

These days, the Army trains everyone on both iron sights and the CCO (red dot), but why would you want to shoot your qual with iron sights if you don't have to?
 

Andino

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I also agree with the other poster who said that Magni's take off process equates to less take off errors, indeed in the UK I can not think of a single blade sail accident off hand.

Thank you. The production numbers of AutoGyros to Magnis are about 2.3:1 (3,000:1,300). I see only one Magni blade-sailing accident (G-CVPM).
However, AutoGyros have had 17 blade-sailing accidents, hence my "6x" comparison (now that I do the math, it's actually 7.37x). And that's without counting <flight-speed rotor RPM violent pitch-up/yaw/rollover crashes when the flat disc pilot suddenly tries to "rotate" close to Vx.

Certainly, all trained autogyro pilots who blade-sailed during take-off "knew how to pre-rotate and take off correctly"...but they did not do so. Why not? Because added complexity increases risk of error. The obvious example is the retractable gear FW airplane. Pilots with a Complex endorsement often enough forget GUMP and three greens, and belly in.

Flexshaft prerotator machines certainly can be blade-sailed (RAF2000 G-BXDE; SCII N767LW), but such is quite rare because their procedure is more simple and less prone to error.

Design determines pilot technique, which then greatly influences outcome.

A flat-disc prerotation technique (required by U-jointed drive-shaft prerotator) is a suboptimal process which invites take-off roll error. Training cannot completely overcome this, and the worse the design the more training must become a palliative.

It's preferable to instead design aircraft which are not so tricky, and many of you have urged such for years regarding the elimination of high thrustlines in autogyros. I suspect that U-jointed drive-shaft prerotators are used because of lower cost and easier parts acquisition, not because they allegedly are a better system than the more expensive flexshaft. Pilots must then "make up the gap" with a more difficult and risky take-off procedure. (Those absurdedly simple nosewheel forks which have no caster are the other blatant example.)

The closest thing we have to a "magic bullet" is optimal design, using the best materials, with thorough training. I think that autogyros could improve markedly in all three (especially the first). However, to continue to throw training at suboptimal designs is to careen down that same old muddy road, feigning bafflement why we get stuck again and again.
 

Andino

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This is completely bass-ackwards. Abid I know you won't agree, but if you truly want to cut down on the accidents CFI's worldwide need to stop churning out Gyroplane Drivers like a puppy mill.
Teach them to fly WITHOUT the damn rotor RPM gauge FIRST and make them PILOTS!

This right here, this mentality is in my opinion the single greatest contributor to the accident rate in gyros.

Sure sure, "If only they had followed the POH" just doesn't cut it.

Ben, I get your "iron sights before red dot" analogy. Long division precedes using a calculator. Real pilotage before a GPS moving map. Old school provides the best foundation, I agree. (I don't go so far as hand patting blades, but I take your point.)

Those machines which can be typically prerotated with aft stick really have no need to confirm rotor RPM during take-off roll. The rotor will spool up naturally, requiring ever so slightly forward stick to become balanced on the mains, which automatically gives the correct AoA for a natural lift off at the proper airspeed. Throw in also a forgiving nosewheel, and autogyro take-offs are mostly free of drama.
 

Andino

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3. 14 CFR (the "FAR"s) contain no criminal provisions. As an administrative agency, the FAA does not have the authority to enact criminal statutes. Federal criminal laws are in Title 18, US Code, as enacted by Congress. A drunk airline pilot can be sued to death in civil court but can't be jailed under the FARs.

Thank you for your thorough and helpful reply. I still find it bizarre that there are no criminal provisions for licenced pilots exhibiting criminal behaviour. A completely besotted driver who wantonly endangered people may be imprisoned, yet a completely besotted pilot will at worst be fined and lose his licence? And what if he continues to fly after that? More finger-wagging of "You naughty boy!"? Seems a recipe for recidivism.
 

BEN S

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If you teach your kid to drive using an automatic transmission, they will not drive as well when they have to use a stick-shift manual.
But is that a "when", or an "if"?
(My son drives a manual, incidentally).

These days, the Army trains everyone on both iron sights and the CCO (red dot), but why would you want to shoot your qual with iron sights if you don't have to?
Tyger, its not about shooting your qual on the range (takeing off under optimal conditions and following the poh). Its more akin to being under fire and your red dot fails (some variable in take off has changed, pilot still struggles to make numbers match). Those rifles still have iron sights as back ups, for when things go wrong. Why carry the extra weight if the soldier doesn't know how to use them? (Hint: the Army has acceptable losses in combat, pilots flying for fun not so much)
 

Sv.grainne

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My experience with my CFI. I prerotate to 170rpm with stick forward, bring the stick full back, release the wheel brakes and start my takeoff roll. Head winds dependent I increase the throttle to the point that the nose wheel lifts off. I try to hold this as I increase the throttle and then lift off increasing throttle till I'm flying. I'm not aware of RRPM at this point but more the feel of the machine and air speed. This has worked well for me and when flying I can say I'm not really aware of RRPM. I'm hoping this is good as I am focused on the sight picture down the runway and feel of the machine. Still learning

Bobby
 
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loftus

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My experience with my CFI. I prerotate to 170rpm, release the wheel brakes and start my takeoff roll, stick back. Head winds dependent I increase the throttle to the point that the nose wheel lifts off. I try to hold this as I increase the throttle and then lift off increasing throttle till I'm flying. I'm not aware of RRPM at this point but more the feel of the machine and air speed. This has worked well for me and when flying I can say I'm not really aware of RRPM. I'm hoping this is good as I am focused on the sight picture down the runway and feel of the machine. Still learning

Bobby
The key of course is that you have prerotated to 170RRPM and you can be quite comfortable with your gradual process of acceleration with stick back, the RRPM will increase and thus lift will increase till she's ready to fly. Personally I think it's more an awareness of lift being created as felt through the nose wheel and your seat than it is an awareness of actual rotor speed. I can't say I can hear an actual RRPM speed that allows me to takeoff, only an increasing awareness of adequate lift being generated as lift is proportional to RRPM. With the engine noise etc I've never had an auditory appreciation of actual RRPM on takeoff.
 
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Philbennett

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I prerotate to 170rpm, release the wheel brakes and start my takeoff roll, stick back.
If you flew a Cavalon/Sport/M24/M16 etc and only pre-rotated to 170rrpm on a nil wind day and your brake release/take off roll were in anyway delayed, slow, distracted or throttle application too gradual then you would have likely flapped the blades before you got to talk about any of the other stuff you wrote about....
 

Andino

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My experience with my CFI. I prerotate to 170rpm, release the wheel brakes and start my takeoff roll, stick back. Head winds dependent I increase the throttle to the point that the nose wheel lifts off. I try to hold this as I increase the throttle and then lift off increasing throttle till I'm flying. I'm not aware of RRPM at this point but more the feel of the machine and air speed. This has worked well for me and when flying I can say I'm not really aware of RRPM. I'm hoping this is good as I am focused on the sight picture down the runway and feel of the machine. Still learning

Bobby
What does your Aviomania POH specify for prerotation procedure: a neutral or aft stick? I'm curious since your machine has a flexshaft prerotator. Thank you, and safe flying!
 

Andino

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If you flew a Cavalon/Sport/M24/M16 etc and only pre-rotated to 170rrpm on a nil wind day and your brake release/take off roll were in anyway delayed, slow, distracted or throttle application too gradual then you would have likely flapped the blades before you got to talk about any of the other stuff you wrote about....
Maybe he does so safely from aft stick prerotation? (But not routinely from neutral stick; I agree.)
 

Sv.grainne

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What does your Aviomania POH specify for prerotation procedure: a neutral or aft stick? I'm curious since your machine has a flexshaft prerotator. Thank you, and safe flying!
Prerotate with stick forward till 120rrpm, slowly bring stick back and increase throttle till 170 rrpm, release brakes, increase power setting, begin takeoff roll. Continue increasing throttle till 190rrpm and watch for 45kts air speed keeping the nose wheel off the ground.
 

Philbennett

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OK so different models different requirements, hence differences training.... but in AutoGyro / Magni even with stick fully aft at those RRPM gives a very small margin
 

TyroGyro

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Hours is clearly a factor. Although I only have reliable data for less than half of the fatals, it shows that:-

65% of dead pilots had fewer than 100 gyro hours. [26/40]
43% of dead pilots had fewer than 50 gyro hours. [17/40]
20% of dead pilots had fewer than 25 gyro hours. [8/40]

In addition, perhaps a further 3% were student solos, hours unknown.

In addition, perhaps a further 7% were either completely unlicensed or had invalid licences, hours unknown...
 
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Andino

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Prerotate with stick forward till 120rrpm, slowly bring stick back and increase throttle till 170 rrpm, release brakes, increase power setting, begin takeoff roll. Continue increasing throttle till 190rrpm and watch for 45kts air speed keeping the nose wheel off the ground.
Thank you. Stick back, 170 rotor RPM, and then roll. From there, the rotor cannott help but increase in RPM as you keep the nosewheel slightly off the ground. That's the flexshaft advantage of already having aft stick/170 rotor RPM before the take-off roll commences. There is no lag time from a flat disc/neutral stick, and nothing extra to remember as the stick is already where it should be. (Reminds me a bit of FW soft-field take-off procedure.) Bobby, your Aviomania has a somewhat castering nosewheel; I would presume that it instills more confidence than the typical pedal linked nosewheel, yes?

Phil, have you ever flown a flexshafted machine using their particular aft stick technique? It is noticeably different from AutoGyro's, and much more forgiving during your warning scenario of "on a nil wind day and your brake release/take off roll were in anyway delayed, slow, distracted or throttle application too gradual."
 

Andino

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Hours is clearly a factor. Although I only have reliable data for less than half of the fatals, it shows that:-

65% of dead pilots had fewer than 100 gyro hours. [26/40]
43% of dead pilots had fewer than 50 gyro hours. [17/40]
20% of dead pilots had fewer than 25 gyro hours. [8/40]

In addition, perhaps a further 3% were student solos, hours unknown.

In addition, perhaps a further 7% were either completely unlicensed or with invalid licences, hours unknown...
Certainly. And the more complex the take-off procedure, the more risk to a new pilot. For example, of the AutoGyro take-off roll blade sailing incidents with pilot hours included, 124 hours was the most experienced pilot (and the rest were <100 hours).

Of the (injury nonspecific) accident data I have with hours listed, 82% (104/127) involved pilots with <200 autogyro hours. The 23 accidents of >200 autogyro hour pilots were generally free of take-off roll blade sailing. I.e., these >200 hour pilots had mastered the flat disc 200 rotpr RPM prerotation procedure. (Over time, people can learn to reliably repeat the wonkiest things.) However, there were quite a few taxiing incidents, mechanical failures, and wind-related incidents. After 200 hours, complacency seems to cause more accidents than lack of skill.
 

BEN S

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Tyrogyro, now if you REALLY want to ruffle some feathers, correlate the ages of the accident pilots to see if you can come up with a demographic pattern.

i.e. "Why yes , you can fly a gyro at 70 years old for the first time sir, but recent studies have proven that even with all your money and free time you have an 82% chance of a blade flap in an ELA before your first 100 hours! Still want to buy it?"
 
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