originally the air national guard was designed as a combat reserve force. after world war ii, its flying units consisted of 72 fighter and 12 light bomber squadrons equipped with obsolescent world war ii propeller-driven aircraft while the active duty air force transitioned to jet fighters. although it had no airlift or tanker units, the air national guard's flying units were equipped with a small number of liaison, trainer, and transport planes, and the air national guard actively sought out new missions and aircraft.