sentences:  1968 Thule Air Base B-52 crash
  
  On 21 January 1968, an aircraft accident (sometimes known as the Thule affair or Thule 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 B28FI thermonuclear 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.