January 21, 1968 - Thule, Greenland
DOD: A B-52 from Plattsburgh Air Force Base, New York, crashed and burned some seven miles southwest of the runway at Thule Air Base, Greenland, while approaching the base to land. Six of the seven crewmembers survived. The bomber carried four nuclear weapons, all of which were destroyed by fire. Some radioactive contamination occurred in the area of the crash, which was on the sea ice. Some 237,000 cubic feet of contaminated ice, snow and water, with crash debris, were removed to an approved storage site in the United States over the course of a four-month operation. Although an unknown amount of contamination was dispersed by the crash, environmental sampling showed normal readings in the area after the cleanup was completed. Representatives of the Danish government monitored the cleanup operation.
CDI: The B-52 was flying the Arctic Circle route as part of the continuous airborne alert operation, "Chrome Dome," involving anywhere from 6 to 50 B-52s. A fire broke out in the navigator's compartment and was soon out of control, spreading smoke throughout the plane. The pilot headed the bomber towards Thule Air Base, located about 700 miles above the Arctic Circle on the northwestern Greenland coast, to attempt an emergency landing. The seven crew members had to eject when the plane was at about 8-9,000 feet and about four miles south of the runway. Six of the crew members parachuted to safety with only slight injuries while one, the co-pilot, died. After it was abandoned, the plane did a 180 degree turn and crashed onto the ice of North Star Bay seven and one-half miles southwest of Thule, whereupon it skidded across the ice in flames and exploded. It is believed that the high explosives in the outer coverings of the four 1.1 megaton H-Bombs aboard detonated, releasing radiation from the plutonium in the bombs and causing fires which destroyed all four. Wreckage of the plane was widely scattered in an area about 300 yards on either side of the plane's path, much of it in "cigarette box-sized" pieces. A team of 70 Air Force and civilian specialists were flown in to monitor radiation and search for debris and the bombs, soon followed by the Navy's special team which had worked at Palomares. The bombs' parts were discovered about ten days later on the snow within 1,000 feet of the path of the plane. A massive collection and removal effort began. The contaminated ice and crash debris were removed to the United States, the bomb debris to the AEC Pantex plant at Amarillo, Texas, where the bombs had been manufactured. A few days after the crash, Secretary of Defense McNamara ordered the removal of nuclear weapons from planes on airborne alert. The alerts were later curtailed and then suspended altogether. The government of Denmark, which owns Greenland and prohibits nuclear weapons on or over their territory, issued a strong protest. There were large demonstrations throughout Denmark against the U.S. and its base at Thule. Costs of the crash, clean-up and compensation ran into the millions of dollars.