The Ente (German: duck) was the world's first full-sized rocket-powered aircraft. It was designed by Alexander Lippisch as a sailplane and first flown under power on June 11, 1928, piloted by as part of the Opel-RAK rocket program led by Fritz von Opel and Max Valier. The Opel RAK.1 was developed as the successor to the "Ente", and was demonstrated successfully to the public in September 1929 with Fritz von Opel as pilot.