W.Green, G.Swanborough The Complete Book of Fighters

WEYMANN W-1 France

   An extraordinarily innovative single-seat fighter completed at Villacoublay by the Societe de St Chamond in the autumn of 1915 to the designs of Charles Terres-Weymann was the W-1, with an extension shaft-driven stern-mounted pusher propeller reminiscent of that used by the 1911 Tatin-Paulhan Torpille. An all-metal, single-bay unstaggered equi-span biplane with ailerons in both upper and lower wings, the W-1 had a slab-sided fuselage occupying the entire wing gap and a cruciform tail with rudders above and below. The pilot was seated immediately ahead of the wings with two fixed machine guns, and an 80 hp Clerget seven-cylinder rotary engine was mounted behind the cockpit at the CG. Entirely enclosed, this engine, which drove a two-bladed propeller aft of the cruciform tail via an extension shaft, drew cooling air from an intake immediately below the pilot’s seat, exhaust gases being ducted to an efflux above and behind. The W-1, which had a tricycle undercarriage and a skid under the ventral fin, offered its pilot excellent visibility from the cockpit. However, engine cooling presented insurmountable problems and testing of the aircraft was abandoned in December 1915 after only two short flights. No data relating to the W-1 appear to have survived other than wing area of 247.58 sq ft (23,00 m2).