In March 1944 the Advanced Twin Engine School was re-designated as the 402d Army Air Force Base Unit. In March 1945, the unit was re-designated as the 249th Army Air Forces Base Unit (Army Air Forces Pilot School, Specialized Four Engine) and jurisdiction was transferred to Second Air Force in June. The mission of La Junta AAF then became the training of replacement heavy bomber pilots in AT-17 Flying Fortress trainers for eventual assignment to B-17 Flying Fortress bombers.
