National Museum of Nuclear Science & History
Frei worked for Stone and Webster Engineering Corporation.
George W. Marquardt served as a captain in the 393rd Bombardment Squadron. Although he was regularly assigned to the Up An’ Atom, he flew in the mission to bomb Hiroshima as the aircraft commander of the Necessary Evil.
Andrew Walker was a member of the Special Engineer Detatchment (SED) at Los Alamos during the Manhattan Project.
