The Douglas C-133 Cargomaster was built in response to a U.S. Air Force requirement for a new strategic air transport. Unlike previous aircraft, the C-133 sported a long tubular fuselage, with high mounted wings, and clam shell rear doors which provided an unobstructed cargo bay. This allowed the aircraft to carry assembled ICBM missiles, and in the later part of its career, it was used to transport Minuteman missiles to and from their silos.