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
Igor Sikorsky 1912. In early 1912, Igor Sikorsky became Chief Engineer of the aircraft division for the Russian Baltic Railroad Car Works ("Russko-Baltiisky Vagonny Zavod" or "R-BVZ") in Saint Petersburg. His work at R-BVZ included the construction of the first four-engine aircraft, the S-21 "Russky Vityaz", which he initially called "Le Grand" when fitted with just two engines, then as the "Bolshoi Baltisky" (The Great Baltic) when fitted with four engines for the first time, each wing panel's pair of powerplants in a "push-pull" tandem configuration previous to the four tractor-engined "Russki Vityaz". He also served as the test pilot for its