Fairchild PT23 Cornell. This plane used the PT19 airframe but with a radial engine fitted. The Fairchild PT-23 was used by the United States Army Air Corps as a primary trainer during World War II. The Air Corps pilots were trained in three stages: Primary, Basic and Advanced, before they were sent to operational units to fly the combat aircraft. The pilots began their training in the simple primary aircraft such as the PT-23.