5. January 21, 1968

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A U.S. nuclear-armed B-52 bomber was flying on a routine mission near its base at Thule, Greenland when a fire broke out aboard the aircraft. Unable to guide the aircraft back to base, the crew bailed out and the bomber crashed into the sea seven miles off the coast of Greenland. Although the high-explosive component of the nuclear warheads onboard exploded, no nuclear detonation occurred. If one had, it would have knocked out communications at the base and given the appearance that the base had been attacked.