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Autogyro study aids

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Autogyro study aids

Old 9th Nov 2016, 14:07
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Autogyro study aids

I'm set up to go on a course to learn to fly an autogyro. It's in France, and the only study guide I can find is a generalised microlight guide, which I already have (this is an add on rating to a microlight PPL, also French)
Can anyone point me at a good guide to flying the beast? I don't need the rest of the stuff such as law and met, but some aerodynamics related to autogyros would be helpful. English or French language. I'm currently flyiing fixed wing, power and gliders.
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Old 9th Nov 2016, 14:45
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Most commonly used ones in the UK are Home or the books by Phil Harwood ("Flying The New Generation Gyrocopter").

The Flight Manual is also a useful (and often overlooked) resource.

Last edited by this is my username; 9th Nov 2016 at 17:05.
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Old 9th Nov 2016, 15:34
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Glasgow university did a study on the aerodynamics a few years ago, based on the bad accident rate at the time.
May be worth looking into. Sorry, don't have a link.
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Old 10th Nov 2016, 05:44
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Glasgow university did a study on the aerodynamics a few years ago

https://publicapps.caa.co.uk/docs/33...2009_02red.pdf

356 pages!
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Old 10th Nov 2016, 08:01
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Not sure what this tells you, but the chap who ran the Glasgow study now works for Loganair ! I've read most of his papers, but they're not as easy reading as the CAA work, nor frankly likely to aid you in learning to fly an gyroplane much.

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Old 10th Nov 2016, 09:49
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British Rotorcraft Association should be able to help.
My limited knowledge of them, they are great fun if flown correctly, some control inputs are completely the reverse of fixed wing, helicopter pilots may have trouble with going up in autorotation, fixed wing pilots, blade stall recovery, pull and pitch up, negative "g" is usually fatal.
Good training is vital.
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Old 10th Nov 2016, 10:06
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Standby... Some control inputs are completely the reverse of fixed wing.... err like what?

Like all aircraft the text book is of less use without the practical context. Best advice is to find an instructor and then let him guide you to appropriate text. Beyond all of that they are very benign to fly. Landing is pretty much as fixed wing, except the gyro is a drag machine so there is little float after rounding out. Take off requires understanding of your particular aircrafts pre-rotation process and then some practice going through the take off roll, wheel balance and airspeed build up post unstick. Upper airwork wise as has been said zero and neg g are not possible due to rapid rotor rpm decay (think drag) but then non aerobatic pilots never get into that condition fixed wing wise so its not as big an issue as it sounds. Overall great aircraft, under rated and yet for 90% of GA arguably the most suitable aircraft available.
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Old 10th Nov 2016, 10:22
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Pardon me, "some inputs the reverse of fixed wing" . If you get into a situation of rotor RPM decay, which is similar to a fixed wing stall. You do not push and increase power, fixed wing fashion. You pull and reduce power to increase the drag through the rotor. This was explained to me during the very small amount of training I did on them. The words used were, " get the disc loaded and keep it loaded.
Sorry to ruffle feathers.
I am no expert on this, never professed to be, and I am not about to argue with a gyro pilot. As I said, my (limited) knowledge of them.

I should add that my limited experience of them was well before the Glasgow investigation. In the days when the thrust line/CofG was more of a problem. Although it was understood.
Modern, lowered thrust line, designs are far safer than the old Bensen B8.
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Old 10th Nov 2016, 11:17
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Thanks everyone. That should be good
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Old 10th Nov 2016, 14:59
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crash - all is cool but personally I just wouldn't describe things as reversed. Forward stick still pitches the nose of the aircraft down, back stick pitches nose up. Right and left stick still roll the aircraft right and left.

Low rotor rpm in a [functioning] gyro is not possible without unloading the rotor - which either means pilot induced [via forward stick] or a great deal of turbulence [the likes of which would not be ambiguous!]. However that is not a stall. I'm unaware of any gyroplane flying that has the ability to stall the entire rotor, certainly not one being operated within the limitations of the POH.

I agree that a very nose high attitude could create the differing response if indeed your fixed wing response is to push rather than simply release the back stick...I'm just not sure I'd describe that as the reverse its just a different response.
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Old 10th Nov 2016, 18:21
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Like I said before - take a look at the Gyropedia link above and / or read Phil Harwood's books. They are the standard texts in the UK and have been translated in to many other languages.

Don't take too much notice of what you see written by aeroplane pilots on forums. I'm sure Crash One is meaning to be helpful but in the nicest possible way his posts aren't doing a very good job of explaining how to handle a gyroplane.

For most of the flight envelope a gyro handles very similarly to a light, draggy aeroplane. It's when you get to the edges of the envelope that things change and life gets more interesting (and much more fun!).

Enjoy your gyro flying!
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Old 11th Nov 2016, 11:12
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Pittsextra.
I didn't mean control function reversals, I meant the action taken with them!
Fixed wing stall recovery, you pitch down, obviously by pushing.
With the gyro you pitch up, obviously by pulling.
Crossed wires here I think. NO not control wires!

Unless of course we really confuse the issue and go really far back to the old Bensen with that overhead inverted T bar that really did work the same as a flexwing micro!!!!

And as I said, limited experience of them.
I'm not trying to explain how to fly them, I just know they can, I repeat, can, bite at the edges of the envelope. I'm not surprised that the newer ones are benign, that's what the Glasgow investigation was about.
As for them flying like a fixed wing, no thanks, if I bank my taildragger to 80 deg and pull hard it will stall, I don't think a gyro will do that, if I landed by pulling till it nearly stopped 3ft above ground I think it would retract the gear, violently! correct me if I'm wrong.

Last edited by Crash one; 11th Nov 2016 at 11:39.
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Old 11th Nov 2016, 17:04
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Crash, I've got a lot (lots and lots!) of time on gyroplanes, and a reasonable amount of time on aeroplanes. Like I said - most of the flight envelope is similar to a fixed wing, it is around the edges of the envelope where it differs. High bank turns are, by most definitions, "around the edges", and if you flare a gyro 3 feet above the runway you are unlikely to have a soft landing.

I suspect you mean well but your posts really aren't very helpful to someone thinking of starting to fly a modern gyroplane. By your own admission you have very limited experience based on an old-style machine. I don't think many people would consider themselves qualified to comment on the flying characteristics of a C172 based on a few hours experience many years ago on a Tiger Moth, but somehow a couple of hours on a gyro seems to make everyone an expert ....

The Glasgow University research hasn't been very well regarded by the industry and has had little impact on modern designs. Glasgow told us that the way to get stability was by having the thrustline close to the vertical CG, and that horizontal stabilisers have little effect on stability. Most modern factory-built gyroplanes have a larger thrust line / CG offset than the one recommended by Glasgow and have great big horizontal stabilisers .....
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Old 11th Nov 2016, 18:17
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Look guys, I just wanted a pointer to a decent textbook or two. Can we save the pistols at dawn for , oh, I don't know, adultery, or heresy or something?
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Old 11th Nov 2016, 22:31
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Learn all you can;

The more you understand how your autogyro works, the safer you'll be;

https://www.faa.gov/regulations_poli...-h-8083-21.pdf

Chapter 15 and onwards is for autogyros.

Flying gyros near the edge of the envelope is not advisable.
There is plenty of fun within it.

I built my own and taught myself to fly it. Great fun. Not a route for the impatient or careless.

The machines are safe. The pilots are the problem.
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Old 12th Nov 2016, 13:56
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The Glasgow University research hasn't been very well regarded by the industry and has had little impact on modern designs. Glasgow told us that the way to get stability was by having the thrustline close to the vertical CG, and that horizontal stabilisers have little effect on stability. Most modern factory-built gyroplanes have a larger thrust line / CG offset than the one recommended by Glasgow and have great big horizontal stabilisers .....
I'm guessing that only one of us read those papers?

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Old 12th Nov 2016, 15:09
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I'm guessing that only one of us read those papers?
It was good few years ago now ... happy to be corrected!

From CAA Paper 2009/002:

1 CG / Thrustline offset. The recommendation that the vertical location of the centre
of mass is within 2 inches of the propeller thrust line is a result of the study and
therefore is reported as such. CAA accepts that closer alignment of the CG and the
thrustline is a sensible design aim to achieve pitch dynamic stability (phugoid
mode) but also has flight test experience of a gyroplane design that achieves good
stability but is well outside of the 2 inch criteria. CAA Flight Test Specialist
qualitative assessment implies that pitch dynamic stability may not be solely a
function of CG/Propeller Thrust alignment for all types of Gyroplane. It is
appreciated that in paragraph 8.3.1 (page 152) of the report it is stated that other
factors can affect the phugoid mode.
MPD 2005-08 was issued 24 August 2005 mandating, in part, restrictions on pilot
experience, VNE and wind/gust speeds for single seat a/c. These could be removed
if acceptable evidence was presented to show that the CG/thrustline offset was
within ± 2 inches. However other restrictions noted in the MPD would still apply.
Advisory material to BCAR Section T.23 now includes ± 2" criteria.

2 Effect of tailplanes. The report also concludes that horizontal tailplanes are largely
ineffective in improving the long term response of pitch dynamic stability (phugoid
mode). This is the result of studies primarily on narrow tandem cockpit enclosures.
A CAA Flight Test Specialist qualitative evaluation of the effects of a horizontal
tailplane on a single side-by-side configuration gyroplane type indicated a degree
of improvement in the phugoid characteristics at higher speed. It is appreciated
that in paragraph 8.3.1 (page 152) of the report it is stated that other factors can
affect the phugoid mode.
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Old 12th Nov 2016, 17:53
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Next on my list.
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Old 12th Nov 2016, 18:37
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I dunno,Back in 1983 just a few circuits with Ken Wallis in the 2 seater ( WA117) ,then off I went and got my licence. I had seen Pee Wee Judge go in at Farnborough in the early 70's and so was wary of neg "g". Then never any problem with the Wallis design. Mind you I never ventured to the limits of the envelope.
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Old 12th Nov 2016, 19:57
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Effect of tailplanes. The report also concludes that horizontal tailplanes are largely
ineffective in improving the long term response of pitch dynamic stability (phugoid
mode). This is the result of studies primarily on narrow tandem cockpit enclosures.
A CAA Flight Test Specialist qualitative evaluation of the effects of a horizontal
tailplane on a single side-by-side configuration gyroplane type indicated a degree
of improvement in the phugoid characteristics at higher speed. It is appreciated
that in paragraph 8.3.1 (page 152) of the report it is stated that other factors can
affect the phugoid mode.
Phugoid is not, so far as I know the major issue with gyroplane LoC / in flight failure - that tends to be SPO related, sometimes with linkages to vertical motion of the pitch inceptor. IIRC, the Glasgow research papers (not the CAA interpretation) looked mainly at SPO and LSS, not the LPO, and were very much about modelling of gyroplane stability, not airworthiness recommendations, which were CAA conclusions (with the exception of the 2" rule of thumb, which IIRC did originate in Glasgow).

A tailplane is fairly self evidently going to damp the SPO, and thus will have a beneficial effect on the risk of LoC. Because the phugoid is nominally constant AoA, you'd not expect it to have all that much effect, unless it incorporated an elevator.

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