Sloan Bicurve
From 1910 to 1912 the American John Sloan built his series of "bicurve" biplanes in a small workshop in the Paris suburb of Charenton. As with so many of the early designers and builders, it is difficult to determine how many of the machines appearing under his name were new ones, or merely earlier ones modified and developed.
His first was shown in 1910, typical of his bicurve designs with the shorter top wing arching down at the tips almost meeting inboard of the tips of the lower wing, with the extended leading and trailing edges of the upper wing joined to those of the lower. The lower wing had some dihedral, and then its tips drooped also, with large ailerons on the trailing edges near the ends. The long uncovered rectangular fuselage sat 2 in tandem behind the engine; a tall rectangular rudder stood up at the rear above a long tailplane set at a high angle on the fuselage. The elevators were connected to a forward elevator mounted on outriggers. The aeroplane rested in front on 2 pairs of wheels with a skid between each pair, and a tailwheel; the latter was replaced with a skid before the end of the year. The lower wings were called lifting surfaces and the upper ones stabilizing surfaces: the theory was that the downward curve of the lower wings would "slow the chute if the engine cut."
(Span: (upper) 8 m; (lower) 10.95 m; chord: (upper) 2 m; (lower) from 2 to 2.9 m at the tip; length: 11.3 m; wing area: 49 sqm; speed: c 75 kmh; 50 hp Gnome with a 2.5 m diameter Sloan propeller)
A similar machine, or the same one altered, was often photographed in flight. The forward elevator was gone, and a 35 hp Labor provided power through chains to the 2 tractor propellers. The pilot sat in a sort of bucket. Another version - or modification - flew next, with the Gnome and a single tractor propeller, front elevator, but with a less-drooping top wing. It crashed in 1911.
Sloan's penultimate reported flying machine was flying in 1912 at Issy, seemingly a throwback to the 1910 designs, with the twin skid of the Concours Militaire entry; a final design was similar to the 1912 military aeroplane but with a small inline 4-cylinder motor.
In the years 1911-1912 he was working on plans fora 18.5-meter span Calais-Dover passenger biplane, with a single big float and a boat-shaped fuselage and a 100 hp Clerget; it was not built.
Johannes