Fast Facts: Unnamed Moon Mission (Ye-6 No. 5)
A power failure caused this Soviet lunar lander to fall back to Earth before reaching orbit.
The mission was not acknowledged at the time by the Soviet Union. Historians have identified it as part of the Soviet Luna series of Moon missions.
This was the fifth Soviet attempt at a lunar soft-landing. The mission was aborted early, during the ascent to Earth orbit, when the launch vehicle’s third stage engine (Blok I) prematurely shut down after 50 seconds of firing (at T+340 seconds).
U.S. Air Force radars in Turkey apparently monitored the failed launch. A subsequent investigation indicated that the engine cut off due to loss of power when a circuit between a battery in the fourth stage (which powered the third stage engine) and the I-100 guidance unit was broken.