Soyuz 1 was the first crewed flight of the first-generation Soyuz 7K-OK spacecraft and Soyuz rocket, designed as part of the Soviet lunar program. It was the first Soviet crewed spaceflight in over two years, and the first Soviet crewed flight following the death of the Chief Designer of the space program Sergei Korolev. Komarov was launched on Soyuz 1 despite failures of the previous uncrewed tests of the 7K-OK, Kosmos 133 and Kosmos 140. A third attempted test flight was a launch failure; a launch abort triggered a malfunction of the launch escape system, causing the rocket to explode on the pad. The escape system successfully pulled the spacecraft to safety.