Sikorsky Aircraft and soon increased prize money to US$25,000. In 2010, Sikorsky Aircraft pledged to increase the prize sponsorship to US$250,000. The Canadian engineers Dr. Todd Reichert and Cameron Robertson developed the world's largest ever human powered helicopter with a team from the [[University of Toronto]]. The first flight of AeroVelo Atlas was achieved in August 2012, the 64-second, 3.3-m-flight that won the prize on June 13, 2013. Sikorsky designates nearly all of its models with S-numbers; numbers S-1 through S-27 were designed by [[Igor Sikorsky]] in the Russian Empire. Later models, especially helicopters, received multiple designations by the military services using
Sikorsky S-19 performance and the aircraft was scrapped after a minor crash. Gotha WD.3 Sikorsky S-19 The Sikorsky S-19 was a Russian twin engine experimental prototype aircraft built late in 1916 by the Russian Baltic Railroad Car Works while Igor Sikorsky was chief engineer of the aircraft manufacturing division. The S-19 was a two bay sesquiplane powered by two Sunbeam Crusader water-cooled V-8 engines installed in push-pull configuration. Arranged as a twin-boom aircraft, it had a large rudder located in the center of the empenage. Two crewmembers occupied cockpits in the foreword most section of the booms in front of the lower