In June, 1941 the United States Army Air Forces (USAAF) was created. Less than six months later the Japanese attacked Pearl Harbour, and the USAAF was immediately ordered to ramp up its number of pilots, not by hundreds, not by thousands, but by tens of thousands.
This presented a major challenge. It wasn’t about getting enough potential pilots in the door, there were plenty of volunteers. It was actually about finding the volunteers with the right skills and temperament to survive training and eventually become pilots.