From TU 226,
Mr.
Henri Le Boloch designed a system for
Brake Flaps in 1920,followed by
Lift Machine with a propellers,and
a
Helicopter in 1934/35,we spoke about him before here;
The first is the subject of the patent 526,166 filed February 20, 1920 and which relates to lower shutters, in fact
brake flaps.
In 1934, he proposed a system lift based on an original principle. A small diameter propeller special shape, the
profile not including than an attack spout with no back surface,rotates horizontally at very high speed flush with
a flat surface. To the very high rotational speeds, the air streams, violently spread by the edge of the propeller
as by a projectile, cannot close immediately behind her. The result is the formation of an intense and remarkably extensive depression. Air nets,by folding back, draw in some so the profile of least resistance determined by the
leading edge.
Such a propeller, even in rotation very fast in the open air, would not lead to no practical results; but, and there it
is the crux of this invention, if this rotation takes place flush with a horizontal plane surface, this surface harvest all
the benefit of the area intense pressure, in the form of a vertical thrust. Of course, the contact must be intimate to compel all the air streams to pass through the upper surface.,it suffices to coat the surface plane with a simple film
of oil very viscous,this device therefore consists of get a pressure difference between the upper part of the plane on which turns the propeller which lifts the column of air at each pass, and the lower part on which is exerted without
constrains atmospheric pressure. The result must be a lifting force.
To roughly quantify, we can say that if the total vacuum existed on the surface swept by the propeller, we would
obtain a force of 10,000 kg per meter square. Like the depression area is only one fifth of the swept area and
admitting 50% of all orders, we arrive at 1000 kg per meter square of swept area.
Editor does not know if work were conducted on the basis of this idea, but in 1935, it was announced that Le Boloch
is studying a helicopter at Saint-Cyr in collaboration with Mr. Toussaint.