Igor Sikorsky On June 27, 1931, Sikorsky filed for a patent for another "direct lift aircraft", and was awarded patent No. 1,994,488 on March 19, 1935. His design plans eventually culminated in the first (tethered) flight of the Vought-Sikorsky VS-300 on September 14, 1939, with the first free flight occurring eight months later on May 24, 1940. Sikorsky's success with the VS-300 led to the R-4, which became the world's first mass-produced helicopter, in 1942. Sikorsky's final VS-300 rotor configuration, comprising a single main rotor and a single antitorque tail rotor, has proven to be one of the most popular helicopter configurations,
Sikorsky S-10 by another 3050 mm and the Gnome engine was replaced by a stronger Monosoupape engine, the S-10 served as both a reconnaissance and trainer on floats with the Baltic Fleet. Russian test pilot Gleb Alekhnovich set a Russian record by flying non-stop 500 km in 4 hours 56 minutes and 12 seconds with the S-10. Data from "History of aircraft construction in the USSR". Sikorsky S-10 The Sikorsky S-10 was a Russian Empiren military twin-float seaplane that served with the Baltic Fleet from the summer of 1913 to 1915. After Igor Sikorsky built the successful Sikorsky S-6 for the Russian