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General control line discussion => Open Forum => Topic started by: Terry Caron on October 02, 2017, 06:43:52 PM

Title: Cute Bipe - what is it?
Post by: Terry Caron on October 02, 2017, 06:43:52 PM
A Pou de Ciel variant?
In a museum, Nashville, TN.
Title: Re: Cute Bipe - what is it?
Post by: Robert Zambelli on October 02, 2017, 07:24:19 PM
Bipe? Don't think so.
Title: Re: Cute Bipe - what is it?
Post by: Elwyn Aud on October 02, 2017, 07:28:38 PM
Flying Flea?
Title: Re: Cute Bipe - what is it?
Post by: wwwarbird on October 02, 2017, 07:57:00 PM

 Piper Flying Fool, predecessor to Sterling's version.  ;D
Title: Re: Cute Bipe - what is it?
Post by: Serge_Krauss on October 02, 2017, 08:36:22 PM
Yes, it's a "Flying Flea" (in English) variant, a tandem-winged aircraft. Engines and cowlings vary in this homebuilt design. My Mignet files are burried; so I can't say much more.
Title: Re: Cute Bipe - what is it?
Post by: Terry Caron on October 02, 2017, 09:04:25 PM
Alrighty. Still cute.
Title: Re: Cute Bipe - what is it?
Post by: dennis lipsett on October 02, 2017, 10:07:46 PM
I believe that the French name for the airplane translates as the French called it the louse of the sky. I believe the name is the Pou du Ceil.

Dennis
Title: Re: Cute Bipe - what is it?
Post by: Robert Whitley on October 02, 2017, 10:46:18 PM
Definitely a "Flying Flea".
Some are still being built including an ultralight variant.
Title: Re: Cute Bipe - what is it?
Post by: Serge_Krauss on October 03, 2017, 06:58:03 AM
I believe that the French name for the airplane translates as the French called it the louse of the sky. I believe the name is the Pou du Ceil.
Dennis

Exactly so.

The "Flea" was designed by Henri Mignet as a solution to his inability to coordinate ailerons with other controls and as a means of getting into the air cheaply. He thus designed a tandem-winged plane in which, among other things, the forward wing was placed above the imoveable aft wing and pivoted for pitch control, in place of elevators. The rudder controlled turns. He built his "HM 14" and flew it successfully. Apparently feeling that if he could fly it, then it must be safe, he wrote a little booklet and sold plans, creating a craze among people wanting affordable flying. Soon many were flying, but fatal accidents were beginning to happen; at low a.o.a. "Fleas" were diving uncontrollably. The French and British governments did wind-tunnel tests on models and a full-sized plane. The tests confirmed that at aoa's of much less than 5o, the negative pitching moments increased to the point that the the limited range of foreward-wing pitch was insufficient to overcome the tendency. Adding incidence range to the front wing helped, but did not eliminate the control reversal that ensued. Moving the c.g. forward actually helped some, but did not entirely solve the problem. So the "Pou du Ciel" was banned in France and grounded in England.

Mignet quickly redesigned the plane with new flatter bottomed airfoils and some other changes, apparently overcoming the lethal problems. Barnaby Wainfan wrote many years later in "Kitplanes" that the location of the plane's center of mass far below the aero center of the plane was a large contributer to its initial instability.

Ultimately, although the movement to build HM-14's was halted during a time that this little plane might have revolutionized private air travel in Europe, many more were built subsequently, quite a few in the U.S. As far as I know, there are still some flying here.

Here are some illustrations, mostly contemporary with Mignet's original work. The U.S. patent (application made 4/16/36) shows features not included in the HM-14, as so many patents do. Its application date indicates that it does not include any redesign features, even though the wing sections shown are not undercambered.