Space Shuttle

STS-51-F, a Space Shuttle Challenger mission launched on 29 July 1985, suffered the failure of one of its three main engines during ascent, forcing the first and only in-flight abort in shuttle history. Rather than attempting an emergency landing, the crew shut down the failing engine and continued into a lower-than-planned orbit, completing the mission successfully. The flight remains a notable example of NASA's abort procedures, and attention to it typically resurfaces around discussions of spaceflight risk and engineering decisions.