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Old 16th Jan 2008, 19:04
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Arrow Autogyro / Gyrocopters

A Couple of images for You Autogyro / Gyrocopters

Ken Wallis Taxying out in G-AXAS http://www.abpic.co.uk/photo/1007150/

And one of the New Rotorsport UK MT-03 Gyrocopters G-JMRE http://www.abpic.co.uk/photo/1088706/

Two seater - a bit cold and Breezy this time of the year !!
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Old 20th Jan 2008, 12:40
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Three more of Ken Wallis's Autogyro Fleet - note all the others in the background !

WA116 G-ARRT


Wallis 201 G-BNDG - Two engined - two propellor Autugyro !



Wallis WA12 G-BAHH

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Old 19th Feb 2008, 19:08
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Came across this one dismantled a couple of weeks ago at Little Snoring
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Old 9th May 2009, 00:54
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Do you guys on here like to share your experience with autogyros?

I am trying to figure out which one of those machines I should aim for buying when I grow older and have the money to do more stupid things...

and would like to hear what you think about different types of autogyros.
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Old 9th May 2009, 00:58
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Biggles
Some of those autogyros look like some kind of a strap-on helicopter thingy's

It must be a very interesting ride for a scared-of-heights helicopter pilot to fly one of these.
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Old 9th May 2009, 02:14
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Helil Ice (from other thread on gyrocopter blades):
Do you guys on here like to share your experience with autogyros?

I am trying to figure out which one of those machines I should aim for buying when I grow older and have the money to do more stupid things...

and would like to hear what you think about different types of autogyros.
We share our hangar with a guy who deals in the RAF gyro. It's been around for a long time now, and is a proven, safe product. It uses a variety of Subaru engines which seem to be durable enough given that they operate at around 5,500 rpm nearly all the time.

However, these RAF's use an engine of 135 - 150 horsepower to move two people (and *no* bags) along at about 60 mph. You're not going anywhere quickly. Nobody in their right mind would use a gyroplane for any kind of cross-country flying. And in fact, in my area nobody does.

Gyros are just "fun flyers," used for messing around in the vicinity of the airport.

Gyros are pretty safe, although you wouldn't know it from their accident rates. But the reason for this is the way they are used. It's no fun flying up high in most gyros (in fact it can be downright scary in an open cockpit machine), so gyros are generally flown low. Really low, like what we helo guys would call mild NOE. Around the airport you'll often see them buzzing around quite low, both upwind and down. And this is where pilots get into trouble...those low-altitude turns near the ground. Happens to so-called "experienced" pilots and newbies alike.

The gyro rotor is tilted pretty far back in cruise flight - maybe ten degrees "nose up" or more. If the engine were to quit, the rotor *must* come to a level attitude for the machine to achieve autorotation - just like any helicopter from a Robbie to a S-92. But because of the way all gyros are built, with the rotor attitude level the cabin is at about a ten degree (or more) nose-down attitude. Thus, if/when the engine quits, many pilots are reluctant to put the nose down far enough to get the disk level. And if you think 10 degrees nose-down looks drastic in a JetRanger (and it does), try it in an open cockpit ship with a little pod-type instrument panel! Yee-ikes! It's like you're staring straight down at the ground. With the rotor rpm low, you just don't have any flare power to arrest the descent. And if you happen to be downwind, rotsa ruck!

Thus, YouTube has various crash videos including one in which - I believe - Ken Wallis's brother crashes "Little Nell" when the engine quits and he doesn't get the nose down far enough.

The guy who shares our hangar is a good pilot and he builds quite nice machines. But I've seen him fly, and it just makes me uncomfortable. I know they can turn into the wind from very low altitudes without power, and I know they can do run-on landings safely with the wheeled gear. But to me, I would just feel too anxious and nervous flying a rotorcraft the way gyros routinely are.

I used to be "big into" gyros some years ago (mid-1990's) when I fantasized about building/flying one. Not so much anymore. Check out www.pra.org for the best poop.

Gyros themselves aren't stupid - it's what people do with them that is.

I love rotorcraft (11,000+ hours proves that). But for my money, I think I'd rather buy a homebuilt kit like a SeaRey. That way I'd be able to take along another person, something more than a box of Kleenex, and go somewhere.

You know what they say about your mileage...
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Old 9th May 2009, 02:31
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FH1100

Thank you for your input.

Seaplanes always have been of interest to me. I saw this one at the NBAA last year in Orlando Florida: ICON Aircraft: Sport Flying Revolution

Looks good doesn't it?
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Old 9th May 2009, 14:27
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If you are interested in gyrocopters, look here:

Rotary Wing Forum

FH1100,

sorry but what you write is ultimate rubbish:

If the engine were to quit, the rotor *must* come to a level
attitude for the machine to achieve autorotation - just like any
helicopter from a Robbie to a S-92.
Gyrocopter is in permanent autorotation, so by engine out you
have to do nothing, or rather pitch up, not down... !!!

These are such experienced helicopter pilots like you (or FW pilots),
who jump into a gyroplane without any training and having no idea,
how such thing flies, and get killed "pushing the stick" on engine out
(which is a sane reflex for them), unloading the rotor, running into PIO,
and crashing...

Besides, RAF is by no means "safe machine" !!!
It has the highest accident rate in the whole gyrocopter history,
due to high thrust line and tendency to power push-over.
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Old 9th May 2009, 15:49
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auto's...

PtKay,

You are obviously an accident waiting to happen...

I quote from " Flying a new generation Gyrocopter" by Phil Harwood.

" Climb out is probably the worst time to get an engine failure and the time between 20ft and 150ft is probably the worst. As soon as you detect an engine failure you must smoothly get the stick forward and the gyrocopter into a nose down attitude as quickly as possible, even if initially the nose down attitude seems too great. It is easy to bleed off speed in the flare. The only way to get speed without power is TOO LOWER THE NOSE. This takes skill and a quick reaction"

FH1100 seems to know his stuff dummy.....
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Old 9th May 2009, 16:00
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If the engine were to quit, the rotor *must* come to a level
attitude for the machine to achieve autorotation
You mean this is knowing the stuff ?

...to achieve autorotation..?????.

Give me a break.

And read with understanding.

The quote you made is referring to very low altitude situation
and climb out and slow flight, where pitch down just levels the flight
and brings you down.

By high speed rapid nose down and bringing
"the rotor .... to a level attitude"
hence stooping the airflow through it, will unload the rotor
with the known consequences.

Last edited by Ptkay; 9th May 2009 at 16:11.
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Old 9th May 2009, 16:12
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PtKay,

OK matey, now you are playing on words and sentence formation...

Your explanation of do nothing or pitch nose up is absolute ****e...

Good luck getting friends to fly with you.......
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Old 9th May 2009, 16:22
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Of course, you are right, on such a "safe" gyrocopter like RAF,
with high thrust line and no horizontal stabilizer,
on engine out you will have a dramatic nose up moment,
which you have to correct immediately.

Centre line thrust machines or equipped with effective horizontal stabilizer
in the prop wash will remain in level flight or have an automatic pitch down reaction
on engine out..
I thought you quoted "modern gyrocopter", not such death traps like RAF.

Fly safe.


And, thank you, I have enough friends who fly with me on regular basis.
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Old 9th May 2009, 17:13
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Ptkay, I think you may be confused about the method that gyroplanes go about their business.

You are correct that gyroplanes are always "in autorotation." But! They are "in autorotation" with the disk tilted way up. (Look at a side shot photograph of just about any gyro in flight.) If the horizontal thrust fails, then the aircraft will (ta da!) slow down due to the tremendous drag of the rotor. Keeping the disk tilted up will simply cause an ever-decreasing decay of rpm. You simply *cannot* expect a gyro without an engine to glide in a level (cabin) attitude.

So what I probably should have said was that to acheive a stabilized autorotation, the disk must be brought to a level attitude. And yes, the only way of doing this is by lowering the nose. Without horizontal thrust from the engine, and without lateral thrust from a tail rotor, unloading the rotor disk might not be such a drastic event. In fact, in the dim recesses of my mind is a statement from a certain Shawn Coyle that you can't get into negative-G in a stabilized auto - although maybe that's not quite correct.

Bottom line is, the rotor needs to be level (or even maybe a degree or two nose down) and you better do what it takes to get it there, even if the sight picture out the front looks uncomfortable. At "high speed" cruise, it won't take such a big push. During a low-altitude engine failure in a high-power/low-airspeed climb, you better get the nose down NOW. Yes, pushing forward on the stick of any autorotating rotor will cause a reduction in rpm. So you're in one of those damned-if-you-do/damned-if-you-don't situations.

If RAF gyros have a high accident rate (and honestly I have not studied gyro accidents, so I cannot verify your statement), then I would ask how many of those accidents are due to material failure? For this is the important question. Gyros generally don't fail their pilots; pilots fail their gyros.

Virtually ALL gyroplanes with rear-mounted engines suffer from a thrust/pitch-coupling. True, the RAF's engine is mounted rather high due to the large prop. But because of the "soft-in-plane" design of the mast (to borrow a phrase from Bell), the effects of power-on/power-off are reduced - at least, that what the high-time RAF guys tell me.

There are also various horizontal stab designs. I've seen a wide one mounted down low on the aft keel (with winglets even!). And most of the RAF's now seem to come with a trimmable stab just behind the cabin and above the engine.

Finally, it must be acknowledged that gyro engines - as good as they are - are not inherently reliable...at least not in the way we've come to expect from a certified Lycoming or Continental engine. All non-certified engines are adaptations of engines from other, non-aviation uses (e.g. Subaru). This must be kept in mind by the pilot: The engine could literally quit at any time. The problem comes with the way gyros are typically operated, which is to say down low, close to the ground and often downwind.

Gyros are not inherently unsafe; they just have peculiar flight characteristics of which the successful gyro pilot must be aware. They are, after all, experimental aircraft and there are reasons why we call them that.
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Old 9th May 2009, 17:40
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FH 1100, I am glad misunderstandings are cleared.

You can avoid rotor/thrust coupling, as you call it, by having Centre Thrust Line (CTL).

Then the prop thrust offset is not compensated by rotor thrust, and by power out
(you are right, gyros seldom use certified engines), you don't have to
compensate for loss of one of the forces in the system.

RAF accident rate is caused not by material failure, but by inherent instability,
comparable with "tail heavy" FW.
You have to be really trained and fast to compensate for turbulence or engine out.

I assume, you are helicopter pilot, so you are used to fly "inherently unstable"
machines, but you can build a stable gyro, that will forgive pilot errors.

And certainly zero or negative G is an absolute NO/NO on gyro.
Teetering rotor will loose rpm, start flapping, take the tail with it, and you are toast.
There is nothing else to keep rotor turning except the airflow down-up.
If you stop that flow, the rotor WILL eventually stop.


Fly safe.
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Old 9th May 2009, 17:54
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A very good discussion here:

Gyroplane Thrustlines vs. Center of Gravity - Rotary Wing Forum

Last edited by Ptkay; 9th May 2009 at 18:48.
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Old 9th May 2009, 19:34
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Regarding RAF safety and construction, I suggest to our UK friends (and all other of you)
who consider flying this gyroplane, to carfully read this AAIB report:

http://www.aaib.gov.uk/cms_resources...BA%2009-07.pdf

Especially the part:

Tests and research
Gyroplane stability research by Glasgow University
(starting page 72)

Short quotations:

‘The gyroplane had unacceptable longitudinal
dynamic stability above 70 mph and unacceptable
directional stability with the doors fitted.


‘The Stabilator dramatically improved the
gyroplane’s trim system however the gyroplane
tested exhibited similar static and dynamic
stability characteristics to a similar gyroplane
tested without a Stabilator.’


The Stabilator, is what FH1100 describes as:
a trimmable stab just behind the cabin and above the engine.
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Old 9th May 2009, 19:46
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Try this one. Xenon 2.

Very well build, stable and easy to fly.

Several flying in Norway and Sweden, not sure about Iceland.
(Of course many in US, Germany, Austria, Hungary, Australia etc.)

CELIER AVIATION
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Old 10th May 2009, 02:27
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FH1100 Pilot how many hours do you have in Gyroplanes?
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Old 10th May 2009, 04:03
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Gyroplane operations

I hold FAA CPL/CFI certificates in gyroplanes and also operate an Air & Space 18A.

In the event of engine failure, and the pilot does nothing, and assuming sufficient altitude, the gyroplane will descend under full control. In a vertical descent rotor rpm will stabilize at a minimum value appropriate for the gross weight. Any translational velocity will increase rotor rpm slightly. For example in the 18A, vertical descent rotor rpm is 200, and best glide (60 mph) is about 240 at gross weight. Ballast is required if a solo pilot weighs less than 150 lb to maintain the CG within limits and to ensure sufficient load to drive the rotor at or above its minimum flight manual speed of 200 rpm.

Providing the 18A is flown within its flight manual limits, rotor rpm is a non issue. About the only time I pay attention to it is during the pretakeoff rotor spin-up to ensure sufficient rpm is available for good liftoff performance.

Checkride maneuvers in the gyroplane include vertical descents, power on and power off, both of which require holding the nose above the horizon. The descents can also be made with bank held on. Rotor rpm is not an issue during these maneuvers.

The reason any type of gyroplane landing is made from a forward glide is to convert airspeed into rotor rpm in the landing flare. This increases rotor thrust and permits the gyroplane to touch down gently with a no-roll landing if there is any wind. A steep or vertical descent to a landing provides no energy reserve to utilize in the landing flare and will result in a bent airframe since the descent rate at touchdown will be too high, e.g. during a zero airspeed descent in the 18A, the VSI is pegged at negative 2,000 fpm.

The 18A approach speed is 45 mph at gross weight and 40 mph when 200 lb. below gross weight.

Last edited by jpphoopha; 10th May 2009 at 06:24.
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Old 10th May 2009, 08:24
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Engine failure on take off

" Climb out is probably the worst time to get an engine failure and the time between 20ft and 150ft is probably the worst. As soon as you detect an engine failure you must smoothly get the stick forward and the gyrocopter into a nose down attitude as quickly as possible, even if initially the nose down attitude seems too great. It is easy to bleed off speed in the flare. The only way to get speed without power is TOO LOWER THE NOSE. This takes skill and a quick reaction"

The reason for lowering the nose after an engine failure on take off is not to enter autorotation (as the gyro is already in autorotative flight) but to gain airspeed so that you can then arrest your rate of descent by flaring to land. If you didn't lower the nose then you will "touch down" (ahem!) with a rather high rate of descent and no means of arresting it.

If the engine fails in normal cruise flight you can more or less keep the stick where it is (depends on the aircraft type) and allow the gyro to enter a zero-airspeed vertical descent - though you'll need to lower the nose and get some airspeed before you reach the ground so that you can flare.

I doubt if many pprune posters would seek to make authoritative-sounding statements about, say, Airbus flight characteristics without ever having flown one. It's one of the odd features of gyros that there are plenty of self-appointed "experts" out there who have little relevant experience.
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