Background
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 contamination.
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
Department of the Air Force
USAF FOIA Response, April 25, 2018 [2 Pages, 0.3MB]
- “Thule Nuclear Weapons Accident DOSE Evaluation Report” dated April 2001 [48 Pages, 0.6MB]
- PROJECT CRESTED ICE – USAF B-52 Accident at Thule, Greenland, 21 January 1968 [214 Pages, 5.5MB]
- USAF Nuclear Safety, Volume 65 (Part 2) Special Edition – Jan/Feb/March 1970, No.1 [100 Pages, 16.6MB]
- Thule Photographs, 72dpi Thumbnails[11 Pages, 3.0MB]
- Search for Personal Information – Thule Nuclear Weapons Accident, November 8, 2017 [6 Pages, 3.0MB]
- USAF FOIA Reading Room Printout Regarding Palomares, Spain and Thule Air Base Nuclear Accidents [2 Pages, 0.5MB]
- Response to Freedom of Information Act for Records Related to Project Crested Ice, 22 November 2017 [12 Pages, 0.7MB]
Central Intelligence Agency (CIA)
CIA Documents on the 1968 B-52 Crash [247 Pages, 47MB]
National Security Agency (NSA)
NSA Documents on the 1968 B-52 Crash [21 Pages, 6.2MB]