8460th Special Weapons Group

By early 1946, with a hasty demobilization decimating the armed forces, MG Leslie Groves looked to the atomic bomb to counter Soviet expansion. He consequently took steps to preserve both the research facilities at Los Alamos and the ability to produce bomb components. With many Manhattan Project scientists leaving to resume civilian careers, Groves also created a new organization to assemble the “Fat Man” (Nagasaki) bomb, which had become the nation’s principal weapon. To form that organization, the War Department ordered sixty-five young officers to Sandia Base, a defunct Army Air Forces facility near Albuquerque, New Mexico. Groves charged those officers, only one of whom had a doctorate in science, “to make absolutely certain that in case of war, or even in the threat of war, the Defense Department would have at its instant disposal teams ready and trained to assemble atomic weapons.”

Given the bomb’s complexity–a collection of hundreds of often heavy, dangerous, and toxic parts–many scientists believed that military personnel could not possibly assemble one. Richard Bice, for instance, described the ten-foot long, five-foot diameter bomb weighing over ten thousand pounds, as a “Rube Goldberg affair that took an assembly team of scientific experts a week’s worth of effort to assemble.”

On 19 August 1946 the unit’s commander, COL Gilbert Dorland, activated the 2761st Engineer Battalion (Special) and set his officers to work. Rather than make each an expert on all aspects of assembly, he formed them into electrical, mechanical, and nuclear teams. Guided by technicians from the Los Alamos Laboratory’s Ordnance Division, the officers learned their specialties, assembled their first bombs, and at year’s end loaded one aboard a B-29. By working simultaneously on the bomb’s subassemblies, Dorland’s officers completed the entire task in a matter of hours rather than the two days the scientists had taken on Tinian in 1945.

Anticipating war with the Soviet Union, which would require delivering large numbers of bombs at undetermined overseas bases from which a B-29 could reach targets in the USSR, the unit, redesignated as the 38th Engineer Battalion (Special) on 1 May 1947, prepared to meet that challenge. They first recruited and trained enough senior enlisted men to form several assembly teams. Thus strengthened, in mid-1947 the unit began preparing for its first major field exercise: assembling a half dozen bombs at a simulated overseas base and dropping an inert bomb at the Inyokern, California, naval testing station.

Having worked out with the 8th Air Force and 509th Bombardment Group a set of standing operating procedures permitting a quick response, the unit conducted Operation AJAX in November 1947. It delivered six workable bombs to the 509th, and the one dropped at Inyokern detonated exactly on time. Dorland’s men, who later called themselves the Sandia Pioneers, had proven soldiers could do the scientists’ job more efficiently and under more demanding circumstances.

With their mission accomplished and their expertise demonstrated, Dorland’s men assumed unanticipated responsibilities. Several of the Pioneers made trips to Norfolk, Virginia, to advise the Navy on how to reconfigure three of its carriers for atomic operations. After guiding the construction of bomb assembly facilities at two Royal Air Force bases, another officer helped the Strategic Air Command design inexpensive bomb assembly facilities for its CONUS bases. Because the Atomic Energy Commission lacked enough technicians to conduct three spring 1948 atomic tests at Eniwetok Island (Operation SANDSTONE), Dorland lent the AEC most of his trained men. They worked closely with the scientists in setting up and operating test equipment and then assembled the devices whose successful detonation demonstrated that Los Alamos had found ways to make more efficient use of scare plutonium and enriched uranium, which permitted a significant expansion of the U.S. atomic stockpile.

In the meantime, other Pioneers, led by LTC John Ord, established the Technical Training Group. In addition to atomic bomb orientations for the armed services’ senior leaders, the group initially trained weaponeers and bomb commanders for Air Force and Navy aircrews. Then in mid-1948, the group initiated its twenty-week bomb assembly course, now attended by sailors and airmen as well as soldiers.

When the men at Eniwetok returned to Sandia in May 1948, Dorland began monthly field exercises extending through the end of 1949. Those increasingly complex exercises would both test new assembly equipment and techniques and permit certification of newly formed assembly teams. From his trained personnel and soldiers graduating from Ord’s bomb assembly course, Dorland also formed four Army teams, now known as Special Weapons Units. Navy graduates formed a team on 1 August 1948, which became the 471st Naval Special Weapons Unit in November. The Air Force’s 502d and 508th Aviation Squadrons received certification in September and December. With Dorland’s unit one of the armed forces’ first truly joint organizations, the Department of Defense redesignated it as the 8460th Special Weapons Group on 20 December 1948.

Looking back years later, MG Groves reflected on the steps taken in 1946. In letters to Dorland and Ord, he praised the Sandia Pioneers for “their imagination and foresight” and claimed that they played “a major pioneer role in an entirely new and extraordinarily difficult” aspect of modern warfare.

© The Army Historical Foundation