my little wooden gyrocopter

Yes, she does look great.
What's that white thing next to her !!!? :)
 
Just following Cierva’s example…………….

Differential horizontal tail surfaces to cancel throttle/torque roll.

Vertical tail surfaces centered in propeller slip stream to eliminate throttle/yaw coupling.

Looks good, JC.
 
I had saved your workshop photos years ago on my computer, but the hard drive failed.
Went to the autogire webpage, but could not find your photos there anymore.

Would you mind sharing them again on the forum, Jean Claude?
 
What a little beauty. I love the tractor designs, but the visibility of pushers, especially the single-seaters can never be surpassed. You are really in the unobstructed air (unless you can rotate your head 360* without moving your butt).
 
That does look sweet!
 
I had been wondering for some time what the state of your project was, JC. Congrats on the progress! I really like the vintage shock absorbers cum not really oleos (no oil in them so I'm a bit at a loss at what to call them)?. This really is a well proven, time honoured design....;-)

You might want to consider moving the rudder connecting rods to the upper and/or lower end of the rudder. That would reduce the bending load on the ruder attachment point in yawed flow where the air stream to one rudder might be partly shadowed by the fuselage. You would probably have to use two rods then. That depends on whether your rudder attachment point is designed for this load.
It will also be interesting to learn how she is in flight, especially regarding rotor shake. My idea is that a tripod rotor mount will almost inevitably be too stiff, this is why small single rotor helicopters like the Brantley, Bell 47 and 206 used very slender rotor masts that almost look like a toothpick.
 
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Thank to all for your encouragement.

"Sandows Shock Absorber" is commonly used, even on
"Spirit of St Louis" of Charles Lindberg.

I did not understand your suggestion of rudders controlling, Juergen. Maybe with a sketch would be clearer to me.
Sans titre.png
It is possible that the rigidity of the mast is a source of strong vibrations. However, since the very rigid mast of the Magni (*) did not lead to that, I think this is a resonance that must avoided, either by a very flexible assembly or by a very rigid assembly.

(*) due to the static strain of the mast inclined forward
 
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Quote: Maybe with a sketch would be clearer to me. /Quote
What I was trying to point out, JC, is that if the rudders are somehow hit by any sort of transverse flow (e.g. a lateral gust) then the fuselage would shadow the upper part of the rudder, thus creating an non symmetric load. I have tried to indicate this by the large blue arrow on the lower part of the rudder and the very small blue arrow with the turbulence on the upper part. This load would create a bending moment that will put fairly large stresses on the attachment points because these are very close together. To reduce those stresses you might want to consider two wire ropes from the fuselage to the top and bottom of the free standing rudder. These ropes would of course have to be attached such, that they are in line with the rudder pivots and that the rope attachment points can swivel while the rudders are turning. Alternatively one could strengthen the rudder pivot.JCtail.jpg
 
It may just be the angle of the photo, but there does not appear to be a lot of prop clearance when the tail rises.
 
I think taildragger gyroplane has three point take of and landing ,no need to rise the tail.
 
Yes, Jan.
The bearing tilts only 10 degrees to the rear, relatively to the flight line of airframe. It is at least 18 degrees for a pusher.
But it tilts 7 degrees forward instead 0 .
My airframe line is 8 degrees when the wheels are on the ground.

Juergen,
Thank you for your drawing.
I was already taken into account this hypothesis of the rudder partially hidden by the structure. The hinges will accept the stress of max cL on the fin tip below, during cL=0 on the other tip, with linearly gradient.
Spacing between hinges is 85 mm thanks to thick profile of HS
 
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At rest, when the cyclic plate is "full back" and the rear blade on his stop, then his tip is half foot above the ground.

During the landing flare, If the disc reaches 30 degrees when the rear wheel on the ground, then the tip yet will at 1.8 ft and the main wheels at .8 ft above the ground.
 
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Some pictures of the gyroplane pending deconfinement.
 

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