August 28, 1986 Associated Press
ALBUQUERQUE, N.M., Aug. 27— Government documents show that a 42,000-pound hydrogen bomb, one of the most powerful ever made, accidentally fell from a bomber near Albuquerque 29 years ago, a newspaper said today.
There was no nuclear blast, but non-nuclear high explosives in the bomb detonated when it hit the ground four and a half miles south of the Kirtland Air Force Base control tower, The Albuquerque Journal reported. The newspaper said it had obtained the documents through the Freedom of Information Act.
Non-nuclear explosives must be set off in a particular manner to create a critical mass in the nuclear material before there is a nuclear explosion, said Rich Garcia, spokesman for the Air Force Weapons Laboratory in Albuquerque.
No one was injured when the bomb, designated Mark 17, hit an uninhabited area owned by the University of New Mexico. However, it created a crater 12 feet deep and 25 feet across, the newspaper said. The documents said minor radioactive contamination had been detected in the crater.
''It is possibly the most powerful bomb we ever made,'' said Dr. Stan Norris, a research associate with the Natural Resources Defense Council, a specialist on nuclear weapons.
The Government documents did not say, but Dr. Norris said most researchers believed the bomb would have had a nuclear explosive force of more than 10 megatons, or 10 million tons of TNT. Dr. Norris said the largest nuclear weapon in the United States arsenal today had a force of 9 megatons.
The atomic bomb dropped on Hiroshima had a force equal to that of 16,000 tons of TNT.
The Nuclear Weapons Databook, a series of reference works published by Ballinger, says the Mark 17 was ''the first droppable thermonuclear bomb to be tested.'' The Mark 17, made at Los Alamos National Laboratory in 1952, was 24 1/2 feet long and 5 feet in diameter. It fell from an Air Force B-36 flying to Kirtland from Texas on May 22, 1957, the Government documents said.
The Government first reported the accident in 1981 in a brief statement saying only that a nuclear weapon of some kind had been dropped. The reason the bomb fell from the airplane, taking the bomb bay doors with it, was not given in the newly released Government documents.