The AT-9 had a low-wing cantilever monoplane configuration, retractable landing gear and was powered by two Lycoming R-680-9 radial engines.

The design featured a small layout, grouping two Lycoming R-680-9 radial engines forward and using a retractable tailwheel landing gear to achieve the performance necessary to meet the requirements of an advanced trainer.

Named the "Fledgling" by Curtiss-Wright, it commonly became known as the "Jeep" in the United States Army Air Forces (USAAF).

[1] The AT-9 was purposely designed to be less stable and proved to be difficult to fly or land, which made it particularly suitable for teaching new pilots to cope with the demanding flight characteristics of a new generation of high-performance, multi-engined aircraft such as the Martin B-26 Marauder and Lockheed P-38 Lightning.

[1] Because of its difficult flying characteristics the AT-9 was not offered for sale to civilians after the war, although many non-flying examples were given to ground schools for training purposes.