| Comments: Designed by Igor Sikorsky and Michael Gluhareff the VS-316 was the world's first helicopter developed specifically for military use, and the first US rotary-wing type to be mass-produced. Derived from the VS-300 the side-by-side two-seat helicopter had a fabric-covered fuselage, and was powered by a 160 hp Warner R-500-3 Super-Scarab seven-cylinder air-cooled radial engine. On December 17, 1940, the USAAC (renamed USAAF on June 20, 1941) ordered one prototype, designated XR-4 and assigned s/n 41-18874. |
