McClenahan: Mechanical Abilities And Small Hands Propelled Frances Dunne’s Manhattan Project Work

Frances Dunne working at the Manhattan Project, c. 1945. Courtesy/Los Alamos Historical Society Archive

Heather McClenahan
Los Alamos Historical Society

Frances Dunne wasn’t sure where or when she was born. Even now, nearly 30 years after her death, much of her life remains a mystery, but her work on the top-secret Manhattan Project is well documented.

Born in 1910, or maybe 1903, probably in Canada, Dunne was an orphan by the age of four and spent years in boarding schools and dreary summer camps. She attended Swarthmore College but did not graduate, contrary to references on the internet.

In 1935, Dunne boarded a train in New York and headed to Mexico, but she changed her mind when she saw a sunset in Tucumcari and decided to make New Mexico her home. She settled in Santa Fe and attended an airplane mechanics course at what was then Boyd Airfield, today’s Santa Fe Regional Airport.

Dunne’s skills were in demand during World War II. After working at military bases in Tucson and San Diego, she had moved up in the airplane maintenance hierarchy and was working on B-24 bombers when she asked to be transferred to Kirtland in Albuquerque so she could return to New Mexico.

However, once there, early in 1944, a man began stalking her. A friend, William Krueger, who happened to be one of the two major builders in wartime Los Alamos, suggested Dunne apply for a job on “the Hill.” Because of her mechanical skills and small hands, she was immediately snapped up by explosives leader George Kistiakowsky.

According to Los Alamos historian Ellen McGehee, Dunne “worked on mock bomb assemblies, smaller-scale versions fired with ‘tuballoy’ (depleted uranium) used in place of the active material (such as plutonium or uranium). Although not their supervisor, Dunne worked in [an] X Division group (X-2) with a crew of SED [Special Engineer Detachment] tech sergeants that she considered to be ‘her boys.’ Frances and the rest of the crew handled all types of explosives and set off experimental shots at several outlying technical areas.”

In Their Day in the Sun: Women of the Manhattan Project, authors Ruth Howes and Caroline Herzenberg wrote that Dunne’s “work demanded considerable mechanical ability and cool nerves. Dunne was the only woman to work at the explosives sites: alpha, beta, and Two Mile Mesa. Her group consisted of herself and thirteen tech sergeants from the Special Engineer Detachment, whom she still calls ‘the boys.’”
In a 1991 interview with the Los Alamos Historical Society, Dunne remembered, “I called them my boys because they waited on me hand and foot.”

Dunne said her most memorable moment working on the Manhattan Project came during the winter of 1944. She went into Kistiakowsky’s office to quit, but he told her she couldn’t.

“What you’re doing is something that’s never been done before. We are making an atomic bomb,” he said.

He went on, saying, “When we drop that bomb, the war is over.”

With that news, Dunne returned to work immediately.

“As the time for the actual use of the bombs approached, a B-29 was flown to Kirtland to test loading procedures,” wrote Howes and Herzenberg in their book. “The only vehicle available to transport the mockup from Los Alamos to Albuquerque was a new C2 wrecker. To avoid attention, the truck made the trip over back roads at night. Dunne, who knew the roads, made the trip with the mockup.”

Dunne remembered that she was working out at Two Mile Mesa when she heard about the end of the war. She marked the occasion by setting off some explosives, which, incidentally, panicked the horses of a Boy Scout troop coming back from the mountains.

“It was really cold, and it was raining, but we banged them off just the same, in celebration,” she said. “We were extremely happy that we had ended the war.”

Some sources claim that Dunne worked for the FBI after World War II, but that has never been confirmed. She lived out her life in Santa Fe, becoming an avid fan of the Capital High School Jaguars sports teams. An article in the Santa Fe New Mexican noted that she had been a fashion model in New York before the war and a professional singer with Guy Lombardo’s band.

Frances Dunne passed away in Santa Fe in January 1993.

Anyone with any more information on Francis Dunne can contact Heather McClenahan at

In honor of Women’s History Month, the Los Alamos Historical Society is featuring women of the Manhattan Project in Los Alamos in its articles for March.