The first officially observed human-powered helicopter to have left the ground was the Da Vinci III in 1989. It was designed and built by students at Cal Poly San Luis Obispo in California, USA. It flew for 7.1 seconds and reached a height of . The second was the Yuri I in 1994, designed and built by students at Nihon University in Japan. It flew for 19.46 seconds and reached an altitude of . On 13 June 2013, the AeroVelo Atlas was the first to complete a flight that lasted 64 seconds and reached an altitude of 3.3 meters, thus winning the Sikorsky Prize.