First jump takeoff in France

Il a réussi! Mais... how has he done it??
 
Il a réussi! Mais... how has he done it??

It is possibly the system jm-urbani has already explained here. The centrifugal force of the rotor displaces a couple of linked spring-loaded weights, changing the pitch of the blades.
 
Interesting that he appears to be using a fixed-pitch wood prop, and fighting the prop thrust with wheel brakes.

Some information on the mass of the rotor would be appreciated, too.
 
More photos
MICHEL CROS 023_reduit.jpgMICHEL CROS 001_reduit.jpg

quelques informations sur le décollage by Michel:
La tête de rotor est géré par le régulateur, qui est verrouillé au lancement à zéro degrés.Le déverrouillage est contrôlé par un vérin électrique, qui sert aussi de butée haute en semi-automatique.Donc la séquence du saut se déroule de la manière
suivante.
Lancement du rotor jusqu'au régime désiré.Position du manche et palonniers au neutre.Ensuite il suffit d'appuyer sur un bouton qui se trouve sur la manette des gaz.Là en même temps, le parking est libéré,les masses du régulateur sont déverrouillées et l'entrainement rotor neutralisé.En même temps la manette des gaz à fond et le manche un peu en arrière en haut du saut.C'est beaucoup plus simple qu'au début.Je précise que je ne dispose que de 80cv à l'hélice
Google Traduction


some information on takeoff by Michel:
The rotor head is managed by the regulator, which is locked when launching at zero degrees. The unlocking is controlled by an electric cylinder, which also serves as a high stop in semi-automatic mode. So the jump sequence takes place in the same way
next.
Launch the rotor to the desired speed Position of the stick and rudders in neutral Then all you have to do is press a button on the throttle At the same time, the parking lot is released, the regulator masses are unlocked and rotor drive neutralized. At the same time the throttle lever fully and the stick a little back at the top of the jump. It's much simpler than at the beginning. I specify that I only have 80hp at the propeller

MICHEL CROS 019_reduit.jpg

accouplement élastique
 
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Call me the party pooper, but it didn't jump all that high, and appeared to almost be behind the power curve for the first few seconds after lift off. Looks like if you needed to take off from a small spot, and don't have any obstacles to clear this would work, but if your trying to clear trees or other structures, you would need some room to build airspeed and establish a climb.
 
At the lowest point of the rear keel, slightly above the plate. There appears to be a flat plate that is moving within the slipstream.
Is this some sort of attitude indicator plane in relation to relative wind?
It seems to be moving slightly at about 25-30 seconds
 
Call me the party pooper, but it didn't jump all that high, and appeared to almost be behind the power curve for the first few seconds after lift off. Looks like if you needed to take off from a small spot, and don't have any obstacles to clear this would work, but if your trying to clear trees or other structures, you would need some room to build airspeed and establish a climb.
Party pooper! ☺️
I think it's an ingenious solution, would certainly be useful for very rough fields, and could probably be further improved.
 
Google translate from the above French language posted twice:

Some information on takeoff by Michel:
The rotor head is managed by the regulator, which is locked when launching at zero degrees. The unlocking is controlled by an electric cylinder, which also serves as a high stop in semi-automatic mode. So the jump sequence takes place in the same way next.
Launch the rotor to the desired speed Position of the stick and rudders in neutral Then all you have to do is press a button on the throttle At the same time, the parking lot is released, the regulator masses are unlocked and rotor drive neutralized. At the same time the throttle lever fully and the stick a little back at the top of the jump. It's much simpler than at the beginning. I specify that I only have 80hp at the propeller
 
:D(y)
As anyone has found attempting to take off from rough ground, it take longer-than-usual both in time as well as in distance for the rotorblades to spin up sufficiently for flight mode. The bumps from moving over the rough ground are transmitted up through the airframe and seem to have a dampening effect, compared to a smooth runway surface. We feel those bumps in the cyclic. Its a wonder to me that the rotorblades finally get up to flight speed when this occurs...

Even though his jump take-off was only several feet & he appeared to drop back down slightly as he builds speed, I once again marvel @ his ingenuity as we finally see it in action!
I find myself wishing this innovation was available to all...
 
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Google Translate can be rather clunky. I would translate a couple of sentences a bit differently (although I am sure some of the french speakers here have better english than I have french).
"The rotor head is managed by the regulator, which is locked at zero degrees at start up."
"Then the jump sequence happens as follows. Spin up the rotor to the required speed, stick and rudder in neutral position, then just press a button located on the throttle."
 
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The technological achievement is even greater in my eyes as Michel manages to propose his solution WITHIN the very strict ultralight regulations enforced in France. Weight and power limitation for single seater are met... Making it accessible for further implementation on factory machines that would accept to explore. The fact he is a very open minded, humble and friendly individual just ice the cake.
 
At the lowest point of the rear keel, slightly above the plate. There appears to be a flat plate that is moving within the slipstream.
Is this some sort of attitude indicator plane in relation to relative wind?
It seems to be moving slightly at about 25-30 seconds
I might be wrong, but it appears he flew down the "runway" (cow pasture) a ways & then we see the rear of his rotorblades presented in a broader angle. It appears that he was flairing & dropping back down onto the grass.
 
Extending the thought further, the opposite seems likely by enabling a pneumatic or electrical cylinder to immediately force the rotorblades into more of an angle of attack so that the machine can settle onto the ground as smooth as a helicopter can from a low hover.

Come in to a flare 10'-30' (or more) AGL, start to descend vertically as we can do in gyroplanes, drop the throttle to idle & activate the mechanism to pitch the rotorblades way past normal flight angle of attack, settling down slower than the Butterfly gyroplane could in the videos as it was flown by Rusty Nance.
 
Kevin, unless I misunderstood Jean Michel, he indicated in a previous discussion that Michel Cros' rotorhead can do exactly that.
If I understood correctly, there is also (additionally) a high-pitch solenoid stop.
Releasing the high-pitch stop at touchdown would accomplish that soft landing.
 
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