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These two engine firings were used to propel the spacecraft to a reentry velocity of 8071 meters / second ( 26 481 feet / second ) which is 299 meters per second ( 981 feet / second ) above orbital velocity . The propulsion system on Compton lacks sufficient fuel to boost the spacecraft to a higher , longer-lived orbit . The physical cause of the accident was 24 missing bolts needed to secure the spacecraft to a device called the turn-over cart , which is used to rotate satellites from a vertical to horizontal position .