They were replaced by the Cessna twin engine trainers, however the AT-17 was seen as "too easy to fly" and were replaced by the more demanding .By January 1943, almost 200 AT-9s were at the airfield.The RP-322 training version of the P-38 began to arrive also in early 1944, and by May, the flying school was involved in four courses of instruction.By far, the largest course was a single-engine advanced course where cadets received instruction on the .By late 1944, there was an ample supply of twin-engine pilots in training and by late 1944, the single-engine T-6 training was discontinued.Williams then began to offer four-engine training with bombers in December.
The B-17 pilot training ended in April 1945, graduating 608 officers for the Flying Fortress program.
Another course was given to experienced pilots who were transitioning to twin-engine aircraft, also in the RP-322.
Later, a night fighter training program was established for pilots on the RP-322 for later transition to the at , California.
As a flying school, numerous runways and auxiliary airfields were constructed.
The main airfield consisted of three concrete 6000' runways aligned NE/SW, ENE/WSW and NE/SW.