That game of darts...

[FO Gyro]

I disagree. I've learnt a couple of things here.

Sometimes people post statements and treat them like fact, and if there are inaccuracies, then they must be respectively pointed out, in a polite manner. The problem is pilots seem to sometimes not like criticism as it seems to attack the Ego. The trick is it mustn't be a personal attack, as I think that is when the thread becomes useless, and should be locked.

[Learjet]

PTKay and Learjet, we all know the theory of gyros and rotor blades in gyrocopters....

The RAF fuselage has no aerodynamic controls therefore could be considered a dead weight hanging below a rotor disc.

To the contrary, may I very politely point out the following aerodynamic forces acting upon the fuselage which will all exert some degree of influence control upon the 'flying disc" and gyro's overall in-flight behaviour. (any gyro)

1. Thrust (and thrust-line)
2. Yaw stability (vertical stabiliser)
3. Yaw control (tail rudder)
4. Pitch dampening (horizontal stabiliser and /or stabilator)
5. Drag
6. Torque (propeller)
7. Precession (propeller)
8. P-Factor (propeller)
9. Weight
10. Lift
11. Slipstream

This is why fuselage is not merely a deadweight with no aerodynamic bearing upon the "flying disc", and it does in fact have a significant impact on the gyro's overall flight performance and characteristics. As mentioned, the fact that a gyro can be flown around the circuit using only rudder control inputs contradicts the assertion that the disc is flown in isolation of the forces acting upon the fuselage (because of the (false) free-swinging pendulum assumption).

Interestingly, a report compiled by Seppo Laine, Emeritus Professor of Aeronautical Engineering at Helsinki University, studied the effects of the horizontal stabiliser on a Magni M16 and concluded that:

"the aerodynamic characteristics of the VPM M16 autogyro, the stability analysis shows that the horizontal tail of this autogyro is necessary for its longitudinal stability stick fixed in horizontal flight. Without a horizontal tail this autogyro would have an unstable short period motion.

http://www.aero.hut.fi/pubs/reports/AAL ... io-2_1.pdf
For a free-hanging deadweight, that's quite a significant control influence.


P.S.
Fairey Rotodyne
Gross weight: 15,000 Kg's.



Weight shift?????

[Vertical Tango]

Weight shift?????

Definitely not in this design nor in the Magni. But the RAF ? I am still not convinced.
I accept all your theory as you explained until now, but for standard gyros that do have their fuselage guided by feathers in their horizontal plane, making it somewhat "rigid" in their flightpath.
The feathers on the RAF are on the rotor and not on the fuselage, making the rotor rigid and not the fuselage (in my way of explaining). Just before input is placed, in my mind there is still a weight shift component. Once input is placed on the rotor, by whatever means, yes all the 90 degrees stuff theory kicks in....

PS I am begging anyone who wants to input on this subject to keep it clean and in an orderly fashion. It is a healthy conversation that does not make anyone flying dangerously. In my mind, in fact we don't even have to understand the full theory of it to be able to fly. That's the job of the designers but still an interesting topic where Eben must give his input and ignore rude remarks.

[PTKay]

Weight shift?????

Definitely not in this design nor in the Magni. But the RAF ? I am still not convinced.....

I still do not understand, how the laws of physics should be different for RAF,
than for other gyroplanes.

The rotor construction (two blade teetering) and controls are almost the same on Magni and RAF.

[PTKay]

...
No wonder why so few post their thoughts as they are so sh.. scared to be bombarded by the fundis.
...

I am not a "fundi". There is just one Newtonian physics.

This is not a matter of religion, faith and opinions. There cannot be "fundamentalists"
and "faint believers" regarding laws of physics, and aerodynamics, in particular.

It is not a matter of faith, but a certainty, that if you'll jump off the 1000ft cliff
without a parachute, you'll end up as a bloody spot at the bottom.

As simple as that.

[FLYNOTE]

I am still confused...but at least on a much higher level

[PTKay]

I am still confused...but at least on a much higher level

Don't worry.

It took me also a substantial amount of time to understand the physics of the gyroplane rotor.
The precession force is something so weird, you cannot apprehend it easily.

All rotorcraft, with their vibration issues, harmonics, lead-lag problems, precession,
Coriolis are by order of magnitude more complex than fixed wing.

[John Boucher]

Flynote... just for you sire

e d c e d c g f f e g f f e g c c b a b c g g g c c b a b c g g g f e d c and to add some character to it, I'll get my sis to sing it for you

[lion]

Flynote... just for you sire

e d c e d c g f f e g f f e g c c b a b c g g g c c b a b c g g g f e d c and to add some character to it, I'll get my sis to sing it for you

Sorry to be off topic - heard your sis sing at Stellenbosch airfield (gyro big fly in) a few years ago, without any background music, in honour of our gyro friends who sadly perished in an accident - what an absolutely amazing voice, have you got any mp3 or similar (singing clips) to share?

Lion.

[John Boucher]

Lion

You know Johan asked me about my sis at the Aeroclub awards and was"shocked" that she had not put a demo tape together for him. Well, she does sing like an angel doesn't she and she gave many a grown man a lump in the throat and tear in the eye that wonderful evening at Stellies.

I think I should prompt her and see if our mate Mr Vliegnoot can just possibly package a deal - what do you think?

[lion]

That would be awesome! I have listened to a lot of singing and in that hangar/hall like environment her voice was incredible. Look forward to hearing her voice again.

Apologies again for moving off topic.

[Vertical Tango]

I think I should prompt her and see if our mate Mr Vliegnoot can just possibly package a deal - what do you think?

It is not off topic ! What a stress relief ...
Your sis must push for this !
I think that a musician has the best job in the world. Have you ever seen a musician not smile in a band ? Do we smile at the office ?
Hey Flynote, I am so fed up with the rubbish around that I have dusted off the trumpet, plugged the HIFI with the Big Band and I am blowing my heart content until my neighbours move.
It should be compulsory to have light music on board when we fly
Seriously, quality voices are so rare ...

[THI]

Sounds like the next NORTH SOUTH's music is sorted!!


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[John Boucher]

Well all you really need is Grumpy doing the band and who knows, I may surprise and have Mel catch a ride but no promises...

When & Where ? Gariep is it?

[THI]

Well all you really need is Grumpy doing the band and who knows, I may surprise and have Mel catch a ride but no promises... When & Where ? Gariep is it?

And after a few rounds I'm sure there will be a few guys joining in

Yes, The plan is to use Gariep, the second last weekend of May (23rd).

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