SNECMA C450 Coleoptere

GREAT ! :)

Coleoptère is the most strange French program in the 50' Many "what if" birds ...
 
Great job! although there are quite a few pictures available for this design and it's relatives, seeing this art is like discovering it for the first time. Boy! It has been a good day.
 
Râââââââââââââh :eek: :eek: :eek: :eek:


Thanks
ouimaitre.gif
Mister Gatial
ouimaitre2.gif
 
If you were among the candidates to the french president election, you would have my vote ;D
 
Eeerh Matej its flight test program was not particularly successfull... :-\
The plane only "flew" for two months, and crashed at its first atempt to make a transition to horizontal flight. Auguste Morel was badly wounded...

The plane otherwise looked fantastic ;)
 
I read somewhere (i have the article in my files but i don't remember from what magazine) that a near helicopter (we can see it in a photo of this article) may be the reason of the crash because of the displacement of air... :(
 
Very interesting! The fact is that the huge airflow of an Helicopter can't help a
tail-sitters at take off...
 
In SNECMA Magazine April 2003, the Coléoptère and its final fate is discribed. About the
crash the folowing is said:
"On that day, Auguste Morel lifted off on his ninth flight, which was to turn into the
almost tragic crash. “Everything happened very quickly,” recalls Michel Bonin. “Along
with Pierre Drouot (the second airframe mechanic), we rolled back the gantry, and
the Coléoptère lifted off. It stabilized, then started a quick descent. We thought it was
going to recover, but it began to fall too quickly and started to oscillate and rotate to
horizontal. We heard the engine scream with the effort. At the last minute, Auguste Morel
was able to eject.” Roger Mouton was on the scene as well:
“I was near the radio truck, and Auguste Morel ejected about 30 meters away from
me. I ran to him at once, but he was badly hurt. We wondered what could have gone
wrong.” One theory at the time was a jammed throttle, preventing the pilot from
using full throttle during takeoff."

All other reports mentioned this oscillation, too, which I think , wouldn't be started by
the downwash from a heli, but by problems with engine response.
 
I looked at my article. I don't remember the magazine (Air fan ? Air magazine ? Avions ? p.52 to 64), but the article was wrote by Alain Clapaud.

The last fly is described p.62 to 64.

There were two hélicos for the test : the first at 400 m high, the second at 1000 m high to materialize these heights. The fly was foreseen to 600 m.

When the oscillations began Morel was at 950 m (!) and he thought it was because of the helicos and he said to the helicos to fly away...

"(...) l'altitude ne dois pas dépasser 600 m et la vitesse horizontale doit rester sous les 7 m/s. Deux Alouette accompagnent le prototype pour matérialiser aux yeux du pilotes les limites verticales de ses évolutions du jour : le premier hélicoptère se poste à 400 m d'altitude, le second à 1000 m. Le 25 juillet, Morel décolle le Coléoptère à la verticale, puis commence le basculement en avant. La manoeuvre se poursuit par le redressement prévu mais à l'issue de celui-ci, l'un des hélicoptères signale au pilote que le plafond est dépassé. Le Coléoptère vole déjà à 950 m. Alors que Morel constate une vitesse verticale de -10 m/s, l'appareil est pris dans un mouvement de roulis et se met en rotation. Des oscillations apparaissent alors, tant en tangage qu'en lacet. Morel analyse rapidement la situation et, se pensant pris dans les turbulences des hélicoptères, demande à ses accompagnateurs de s'éloigner rapidement. Le C-450 s'enfonce de plus en plus vite. Le pilote met alors plein gaz pour stopper cette descente maintenant très rapide, mais il est déjà trop tard. (...)"

we can see too a photo with the C-450 and one Alouette hélico flying together p.63. It's wrote under :
"Le C.450 lors d'un vol d'essai. Noter la présence d'une Alouette à proximité du prototype, une proximité qui va peut-être expliquer la perte de l'appareil d'essai." = the proximity of the helico is maybe the explanation for the crash...
 
Archibald said:
Eeerh Matej its flight test program was not particularly successfull... :-\
The plane only "flew" for two months, and crashed at its first attempt to make a transition to horizontal flight. Auguste Morel was badly wounded...


Its true, I know, but one crash is nothing for me. Just imagine how many times the Harrier crashed. Its a pity that they did not continue in development.
 
Yeah, I'm a nasty mitpicking... this machine was rather interesting but, as with all tail sitters, main problem would have been landing.
Au fait, with modern FBW, videos cameras and others "synthetic visions" maybe a tail-sitter could be viable option today ? If you ask a computer to land the machine instead of the pilot ;)
the V-22 needed 20 years to enter service, so why not resurrecting the Coleoptere with a M88 ?
 
I think, it wasn't just the Coléoptère, it was the whole tail sitter concept, that
was officially cancelled, although several other designs were coming up later.
But problems with vertical oscillations were encountered with other designs, like
the Lockheed XFV-1, too, absolute precise engine control was essential, but during
these times probaby not on nowadays standards, and pilots view for landing probably
less than good in all built designs. And payload would have been severely restricted,
as there was no possiblity for STOL. The tail sitter is an interesting idea, but the niche,
where it could succeed is very small, I think. And , as mostly, there may have been
some obscure political reasons ...
 
Interesting in Snecma Coléoptère history : it was the first French-German program (and in fact probably the first german military program). Very interesting new archives with some good information (technical and political view). See at the end of 2007 in Le Fana ... ;D
 
[quote author=Jemiba]
The tail sitter is an interesting idea, but the niche, where it could succeed is very small, I think. [/quote]

Methink the niche for tail sitters is basically ship point defence, which is rather well taken these days by various SAMs.

RIP to a concept which was so glamorous when we were children. ;D
 

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