Stupid Question

[The Last Church]

Why can't Gyros be made to hover? Would not
simple power to the rotor make this possable?

 

[scottessex]

Well then you would have a helicopter, and helicopters use complicated, (expensive) transmissions, collective pitch rotorhead tail rotor etc.
That's the beauty of a gyro, the simplicity. everything is a comprimise.

 

[JByrd]

Good Question

Good Question

In my view, questions are brave attempts to get answers and learn something.

Gyros can be made to hover in still air for a moment or two by utilizing an overspeed of the rotor, but this would be momentary until the excess potential energy was exhausted.

But consider why gyros are what they are. The cost, weight, and complexity of adding a robust drive to the rotor is not a part of the design criteria nor is continuous hovering flight.

I will speak for myself in the matter the one reason I like the idea (and this is still an idea) of eventually owning and flying a gyro is:

Advantages:

(1) Small item, easy to trailer and store. One person operation if necessary.
(2) Relatively low cost, actually the most affordable personal avaition I know of.
(3) Simple fuels.
(4) Light weight.
(5) Short takeoff and landing.
(6) Relatively low airspeed, but enough endurance to fly 1-2 hour tour.
(7) Simple engines, though they still require great care.
(8) Hovering is not a requirement.
(9) Still able to carry radio, mode-c transponder, small amount of payload.
(10) Open cockpit flying at it's best.
(11) A support group that offers hundreds of person-years of experience.
(12) FAA recognition.
(13) Competent flight instructors are available, but not widespread.
(14) Not a guy-only thing.

Disadvantages:

(1) Crashworthiness is very poor.
(2) Bird strikes can be a serious problem.
(3) Deliberate crosswind landings appear to be problematic.
(4) The landing flare must be properly mastered.
(5) I have a personal requirement to avoid open belt driven reduction drives.
(6) Stability and control margins appear to be less forgiving than fixed wing.
(7) Cabin heat only on the upper end machines.
(8) Flying in rain probably not the best idea.

It think I got a bit off-topic. But anyway, If you want or need to hover, the helicopter is your next brochure. Bring along about 5-25x more $.

I am cheap and I admit to it.

Jim.

 

[Doug Riley]

Jim: Even a few of the problems you cite aren't, really.

There are enough different gyro landing styles to satisfy just about everyone. The middle-of-the road version of a flare is no different from a fixed-wing flare aside, perhaps, from being easier to master. Remember that, unlike a FW plane, the gyro doesn't execute an outright stall and just quit flying when you flare it. It settles in with the rotor still lifting.

You can do a higher, more radical flare for a zero-roll landing, or even overspeed the rotor with a sharp bank just before landing for a helicopter-like arrival. At the other extreme, you cna do a run-on landing that's so greasy smooth that you may have to look to see when you've touched.

Crosswind landings are also easier than in a FW plane. You can cross a gyro's controls without the risk of a spin entry. The gyro doesn't sag to one side in a slip to anywhere near the extent that a FW plane does. In a really radical cross-wind, you can just land across the runway.

Crashworthiness must be examined in context. No aircraft is survivable in a free-fall from 500 feet. A gyro whose rotor is still working SHOULD arrive at a slow enough speed that a high-G cage isn't needed. Yes, there's room for improvement in gyro crashworthiness; a light steel-tube frame such as the Barnett or Little Wing machines have would be a good choice.

Stability is a matter of design. Gyro pilots haven't been very demanding of their designers on this score. It's just as easy to design a stable gyro as an unstable one. The truly stable machines are every bit as mellow as FW planes; more so when you consider that stall-spin is a form of catastrophic instability that we don't have to deal with.

 

[JByrd]

Hi Doug,

Hi Doug,

Hi Doug, thanks for the comments. I had not thought about the sharp turn to overspeed the rotor a bit before flare.

I am hoping to make one of the fly-ins sometime soon. Last summer I wanted to come to Mentone but a working deadline got in the way. I wanted to stop by Chris Burgess's location too, but that also fell by the wayside.

Tell you what, if you would, send your home phone to [email protected]. I would like to chat a bit with you on a weekend evening at your convenience.

Thanks,

Jim

 

[The Last Church]

The fact that you can spin up the rotor prior to take off run means spinning the rotor is cheap and easy. I see no reason one couldn't spin the rotor with power long enough to hover for a few min.

 

[Crash one]

What about the torque/counter-rotation of the rest of the gyro?
Trevor

 

[Alan Coats]

Michael,

On a simple gyro you can use power to spin the rotors until they generate enough lift to make the gyro light on its gear. Once the gyro gets light there is nothing to stop the counter rotation from the torque. The airframe would start rotating in the opposite direction of the rotor.

Alan

 

[The Last Church]

Yes I understand but there should be a cheap way to counter that. Like counter rotating blades.
or a small J.A.T.O. that would alow 20 minets total. You know just enough for 3 or 4 take offs or landings. Or use the same thing a helocopter does only smaller.
There are helocopters that do use counter rotating props and it does eliminate the problem.

 

[brett s]

Ever looked close at a helicopter's control system & drivetrain and then compared it to a typical gyro? They are an order of magnitude apart in complexity, and that translates to a lot more money - both for initial purchase & maintenance.

 

[The Last Church]

I found one

I found one

Ever looked close at a helicopter's control system & drivetrain and then compared it to a typical gyro? They are an order of magnitude apart in complexity, and that translates to a lot more money - both for initial purchase & maintenance.

See pictures