Twin-Engine Gyro CFI

Ron E

Just Want To Have Fun!
Joined
Nov 23, 2006
Messages
773
Location
Lillian, AL, USA
If someone built a twin-engine gyroplane under the EAB rules (pusher-tractor configuration for example), are there any CFI's in this country that can sign-off the pilot to fly it legally ?
 
Interesting question.

I can't seem to find a test standards manual for multi-engine gyroplane. Is there such an animal as a private multi-engine gyroplane rating? And in a tractor/pusher axial thrust configuration (such as a Cessna Skymaster), is there an axial thrust sign-off?

I'd bet it never came up.

*JC*
 
If someone built a twin-engine gyroplane under the EAB rules (pusher-tractor configuration for example), are there any CFI's in this country that can sign-off the pilot to fly it legally ?

Unlike airplanes, the Rotorcraft category does not have separate single and multi-engine classes. For example, if you have a helicopter license earned in a single engine Robinson, you can legally fly a twin-engined Bell without getting another rating. There are no limits on the number of engines for helicopters or gyros for a Private or Commercial certificate with a Rotorcraft-Helicopter or Rotorcraft -Gyroplane rating. Likewise, CFI privileges don't depend on the number of engines.

Sport pilot privileges limit you to Light Sport Aircraft, and the definition for those says "(6) A single, reciprocating engine, if powered."
 
Twin Engine Gyro

Twin Engine Gyro

Unlike airplanes, the Rotorcraft category does not have separate single and multi-engine classes. For example, if you have a helicopter license earned in a single engine Robinson, you can legally fly a twin-engined Bell without getting another rating. There are no limits on the number of engines for helicopters or gyros for a Private or Commercial certificate with a Rotorcraft-Helicopter or Rotorcraft -Gyroplane rating. Likewise, CFI privileges don't depend on the number of engines.

Sport pilot privileges limit you to Light Sport Aircraft, and the definition for those says "(6) A single, reciprocating engine, if powered."

Thanks, that's very good to hear!

I knew sport pilot privileges wouldn't apply and Part 103 would not be helpful either, because of the second engine, even though an ultralight could be put together.

It seems a 3rd class medical for non-commercial use would be required, not just a state driver's license like the Spot pilot rules allow.
 
Yes, you would need a medical for sure.
 
...I can't seem to find a test standards manual for multi-engine gyroplane. Is there such an animal as a private multi-engine gyroplane rating? And in a tractor/pusher axial thrust configuration (such as a Cessna Skymaster), is there an axial thrust sign-off?

I'd bet it never came up...

This is an interesting area. Twin-engine helicopters don't require a multi-engine rating because the only change when an engine fails is a reduction in power. When a traditional fixed-wing twin loses a side, there are procedures unique to handling the resulting yaw issues, and the FAA wants specific training for them.

In a twin-engine gyroplane, assuming each engine was driving its own prop, and they were offset from the longitudinal CG, you'd face yaw issues similar to losing an engine in a traditional fixed-wing twin. I'm not sure how you'd train. I'm not sure it would even be required...how can the FAA require training in an aircraft that has never existed, with a CFI who's never seen a multi-engine gyro before yours?

There's also the issue of defining "twin engine." If you have redundant single-rotor Wankel go-cart engines running through sprag clutches to belt-drive a single prop, I'm not sure it's a multi-engine aircraft. It's more analogous to a multi-cylinder piston single than a twin.

IIRC, anyone who earned his multi-engine rating in a Cessna 337 had it limited to centerline thrust only, in much the same way taking your private checkride in a single-place gyro results in a restriction against carrying passengers, or passing a private ASEL with no night training earns a certificate with a limitation of day/VFR.
 
I thought I remembered that Bensen built a gyro (B-16 maybe?) with two engines.
If not, I'm sure that a hobbyist somewhere has done it at some time.

Under the current rules, the FAA can't do anything about it. The FAA cannot require any special training or testing for such a thing without going through the entire rule-making process. That's what they did when it looked like civil tilt-rotors might be coming -- they created rules for a "powered lift" category.

If you had a Fairey Rotordyne today (two big laterally offset engines -- NOT tilting -- driving props, tip jets for takeoff but an unpowered rotor in cruise), the FAA would be in a real quandary to regulate it with no current rules directed to gyrodynes.
 
Year ago

Year ago

Interesting question.

I can't seem to find a test standards manual for multi-engine gyroplane. Is there such an animal as a private multi-engine gyroplane rating? And in a tractor/pusher axial thrust configuration (such as a Cessna Skymaster), is there an axial thrust sign-off?

I'd bet it never came up.

*JC*

When I took multi-engine training back in the Sixties, if you took your check-ride in a Skymaster or any other center-line-thrust aircraft the FAA put a center-line-thrust only limitation on your rating.

Suppose its the same now.
 
Yes, still the same for airplanes. No such rules for rotorcraft.
 
Twin engine side-by-side makes absolutely no sense to me whatsoever. What makes perfect sense is front and rear, tractor and pusher. Now THAT would be totally cool. I don't care who you are, if you suddenly lose an engine in the aforementioned, you are going to go sideways, and more than likely roll and die. So what use is the second motor except more maintenance? It won't make the gyro any safer. But fore and aft would be. You could even be like Rutan and shut one down to save gas.
 
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As several instructors have said, airplanes have a twin-engine class because it is needed. Rotorcraft don't. You can fly an experimental aircraft with as many engines as you can install, with no multi-engine rating. You need the rating if you are going to carry passengers. That's nice, but you're nuts if you fly asymmetric-thrust aircraft without thorough training. There are some concepts that come up in twin airplanes that just don't matter in singles. Many twins perform very very poorly with one engine out, and can't hold altitude unless flown with great precision.

The issue with inline thrust is this: pilots unaware that the rear engine has stopped (or attempting takeoff without starting it). Seriously. Inline thrust twins also perform raggedly single-engine -- you're truly in an emergency with one out, whether you choose to declare it or not. Helicopter designers do a lot of work to ensure that engine failures in two- and three-engine helicopters are clearly annunciated to the pilot(s) for the same reason, you're unlikely to notice the loss of the engine's sound and it might take a while to figure out you've lost the power in some flight regimes. In climb you'd notice it straight away.

Along with the well-known example of the Cessna 336/337 Skymaster, there are a few other civil push-pull twins. The FAA also gives a "centerline thrust" limit to military pilots who convert their licenses if they haven't flown planes with a significant thrustline offset. For example, a guy I knew had to get this taken off in a Seneca because the only twins he'd flown were the T-38 and the F-4, both of which have minimal thrustline offsets. On the other hand, C-130 or C-5 pilots are granted a normal multiengine rating as they've had to deal with asymmetric thrust (in the simulator anyway). I'm not sure if this is one of the FAA rules that's inspector-dependent.

A twin-engine gyroplane isn't necessarily hazardous. After all twin-engine airplanes have adequate rudder to keep the machine straight when one engine goes, there's no reason a gyro couldn't be designed that way. However I don't think that the second engine buys you a lot, especially when you realize that in an engine out situation it becomes that much more dead weight. You have the weight of the powerplant (engine, prop) and the weight of your associated structure (engine mount, frame reinforcement). Weight is your bitter enemy in any flying machine.

What would you gain from a second powerplant? More climb, perhaps. More fuel burn, certainly. No speed (gyros are already drag-limited). No safety, really (gyro fatalities result from many things, but not usually from gyro engine-outs. Engine-outs lead to a photo thread in Rotary Forum, in which your buddies help you drag the gyro out of the bean field). The only reason to do it is to be the guy that did it, but don't think it's going to have a practical use or catch on. I like that you're thinking imaginatively, but you have to think it all the way through: is what I want to design likely to be better than what's already out there? If the answer is "no," you can still build it if you want. It's a free country, after all! Just know you're doing it for yourself, and you'll be okay.

cheers

-=K=-
 
Thanks everybody for your info and comments.

What I would like to do, with peace of mind, is be able to fly a straight line on a cross-country over things and places (water, tall pine trees, cities, residential areas, etc.) one would not want to otherwise land on, if an engine failure occurred.

What I have in mind is a pusher-tractor CLT machine based on my Rotor Scooter, but just a little longer with the CG redistributed, with two smaller, lighter engines, and separate fuel tanks. To be worthy of the effort , the gyro, with a fat pilot on board, must have enough power to at least maintain altitude on one engine, or better yet, be able to climb 100 to 200 fpm on a hot day.

The engines I have in mind can produce a little more combined HP than a single MZ202, but have a combined weight less than a MZ202.

Such a machine I believe would permit flying at minimum legal altitudes with more safety, especially on cross-country trips. Flying at lower altitudes keeps you out of the way of faster fixed-wing aircraft reducing conflicts, keeps you "under the radar" and provides the pilot a better view of the various neighborhoods on your flight path.

Since the rear engine would be just inches from the back of the pilot's seat, no engine-out annunciation would be required on the machine I have laid-out on my Waffle House napkin.

I'm glad to hear the FAA hasn't closed the door on this potential next project.
 
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Twin engine gyros have been built by several people including Gary Goldsberry/Art Evans and Jack Craft to mention a some. Here is a link that shows the Craft machine. I would think that if there was a distinct advantage to a twin enging gyro that they would have become popular and common place by now.

http://www.youtube.com/watch?v=sDl1V8mLJu8
 
Twin-Engine Gyro

Twin-Engine Gyro

Twin engine gyros have been built by several people including Gary Goldsberry/Art Evans and Jack Craft to mention a some. Here is a link that shows the Craft machine. I would think that if there was a distinct advantage to a twin enging gyro that they would have become popular and common place by now.

Dean,

My concern was merely the training issue and legal flight of such a machine in this country.

There would be no reason to consider building one if the pilot could not get professional-grade training in the USA and the machine could not be legally flown here.

The two twin-engine gyros I know about were made by Craft and Dr. Bensen. I haven't previously heard about the machine made by Art Evans and Gary Goldsberry.

Remember, I am interested in a cross-country machine, not an airport circling machine. Logically thinking, a well thought-out pusher-tractor, twin-engine gyro would have the same safety and reliability benefits as a twin-engine fixed wing aircraft.

The fact that such a gyro is not already a "mainstream" , popular aircraft does not deter me at all from considering building one, or even a hundred of them.
 
Ron E. - In Florida, Georgia and Louisiana you'll make the alligators mad if you rob them of the opportunity for a meal by adding a second engine.

By all means, dream on and then build. You won't have to fly IFR (I follow roads) or IFF (I follow fields) with a second engine that provides a rate-of-climb by itself.

Don't make the mistake of using a common fuel tank. If you have contaminated fuel, both engines quit.

Dave J.
 
This is interesting, I'm glad that we are all EXperimenting in these field, great minds are coming together for the future quest in flight. Keep on flying.
 
GBA had one

GBA had one

In the south hangar at Buckeye.. Yes it was a Sky Master.. I never saw it fly and didn't take any pix of it either...

I believe that Jim Mayfield did pilot it at one time..

Sure that he has pix of it..

Steve
 
Hi all,
Multi-engined EAB aircraft only require single engine ratings. The first aircraft I certified was an AirCam, it had two Rotax 2 strokes on the wing. The FAA was present a the certification and the question came up.
Remember, until the recent change, you could fly a gyro, helo or fixed wing with a rating in any one of them. A private pilot fixed wing could fly a Rotorway Exec on his FW license and carry passengers.
This so called "loop hole" was closed when LSA rules came into effect. Now you have to have the appropriate rating to fly with a passenger. You also need a solo sign-off, from a CFI, to fly solo.
 
This so called "loop hole" was closed when LSA rules came into effect. Now you have to have the appropriate rating to fly with a passenger. You also need a solo sign-off, from a CFI, to fly solo.

Tom,

Are you saying a pilot with a fixed-wing PPL would need a sign-off from a gyro CFI in order to solo a single place gyroplane? If so would that solo sign-off also have an expiration date, 90 days?
.
 
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