Summary: In response to a congressional request, GAO identified the types of changes that the National Aeronautics and Space Administration (NASA) made to the space shuttle's flight hardware, focusing on enhancements: (1) it made to flight hardware; (2) that cost at least $5 million each; and (3) it implemented from 1981 through 1987.
GAO found that NASA: (1) made 56 changes to the space shuttle; (2) initiated 31 changes before the Challenger accident and 25 after the accident; (3) budgeted about $403 million in three increments through 1993; (4) awarded a $198.2 million development contract for the first increment; and (5) estimated that the cost of the changes would total about $2.4 billion. GAO also found that the primary justifications for making the changes included: (1) studies which evaluated existing system designs; (2) the high costs of repairing outdated equipment; (3) improving the reliability of existing components; (4) demonstrating and improving component capabilities; (5) correcting components that were not fully functioning as designed or as necessary; (6) replacing obsolete parts; and (7) increasing safety.
