Mars 1969b
Launch date:Nation:
Outcome: failure
Wikipedia - "Mars 2M No.522 was launched at 10:33:00 UTC on 2 April 1969 atop a Proton-K 8K78K carrier rocket with a Blok D upper stage, flying from Baikonur Cosmodrome Site 81/24. One of the first stage engines caught fire almost immediately at liftoff. The remaining engines tried to compensate, but trying to lift a booster with a full load of propellant at low altitude was too much for them. The Proton climbed to about 100 meters (330 feet) before pitching over and nosediving into the ground just outside the launch complex. Subsequent examination found that a missing drain plug allowed nitrogen tetroxide to leak out and start a fire."
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Jan 14