Soyuz 1 (Russian: Союз 1 , Union 1) was a manned spaceflight of the Soviet space program. Launched into orbit on 23 April 1967 carrying cosmonaut Colonel Vladimir Komarov, Soyuz 1 was the first crewed flight of the Soyuz spacecraft. The mission plan was complex, involving a rendezvous with Soyuz 2 and an exchange of crew members before returning to Earth. However, the launch of Soyuz 2 was called off due to thunderstorms.