Mauboussin M.40 Hémiptère
A single-seat tandem-wing research aircraft of 1936. Mauboussin argued that with the tandem wing arrangement of the wings, and the c of g is properly located, the front wing will stall first, putting the machine into a dive before it can go into a spin. If, therefore, the ailerons are transferred from the fron to the rear wing, there should be adequate control on the unstalled wing; and even if the front should have a slight tndency to spin it will be prevented by the unstalled and fully controlled rear wing from dragging the machine as a whole into a spin.
The fundamental design of the Hémiptère involves front and rear wings of different aerofoil sections, and arranged with the rear wing mounted on top of the fuselage, while the front wing is attached to the bottom of the fuselage. There is a decalage of three degrees, as the front wing is at an angle of three degrees when the wing is a 0 degree incidence. The arrangement is that of a heavy negative stagger, the distance between the front and rear wing being equal to the chord of the front wing.
M.40: c/n 01 F-AOYZ, endplate fins on high rear wing, influenced by Peyret project.
Engine: 1 x 40 hp Train 4A