On 21
January 1968, an aircraft accident involving a United States Air Force (USAF)
B-52 bomber occurred near Thule Air Base in the Danish territory of Greenland.
The aircraft was carrying four hydrogen bombs on a Cold War”Chrome Dome” alert
mission over Baffin Bay when a cabin fire forced the crew to abandon the
aircraft before they could carry out an emergency landing at Thule Air Base.
Six crew members ejected safely, but one who did not have an ejection seat was
killed while trying to bail out. The bomber crashed onto sea ice in North Star
Bay, Greenland, causing the conventional explosives aboard to detonate and
the nuclear payload to rupture and disperse, which resulted in radioactive

The United
States and Denmark launched an intensive clean-up and recovery operation, but
the secondary stage of one of the nuclear weapons could not be accounted for
after the operation completed. USAF Strategic Air Command “Chrome Dome”
operations were discontinued immediately after the accident, which highlighted
the safety and political risks of the missions. Safety procedures were reviewed
and more stable explosives were developed for use in nuclear weapons. (Description of event courtesy of Wikipedia)

Declassified Documents

National Security Agency

Documents on the 1968 B-52 Crash
[21 Pages, 6.2MB]