During the Second World War, Castle Air Force Base was known as Merced Army Air Field. Thousands of Aviation Cadets took their basic flight training there in BT-13s. They were as common a sight over the San Joaquin Valley as B-52s and KC-135s were in the 70's and 80's. Several other air fields in the valley also were used for primary and basic training.
The Valiant was also known as the "Vultee Vibrator", for the shaking the canopy did when the aircraft was diving or spinning. The aircraft on display at Castle Air Museum is painted in the colors of aircraft assigned to Merced Army Air Field in 1942.