The AT-9 twin-engine trainer was difficult to fly and to land. It has been suggested this was entirely intentional, but the aircraft was underpowered and always close to stalling, and was phased out in 1944. It was used mainly to train P-38 pilots. 42-57038 was written off at Yuma Auxiliary Army Airfield No 2 on 25 August 1943. AT-9s were based at Yuma too but the A code points at Douglas Army Air Field, also in Arizona. Photo from: National Archives at College Park, Maryland

The AT-9 advanced trainer was used to bridge the gap between single-engine trainers and twin-engine combat aircraft. The AT-9 was not easy to fly or land, making it particularly suitable for teaching new pilots to cope with the demanding flight characteristics of a new generation of high-performance, multi-engine aircraft such as the B-26 and P-38. This AT-9 at the National Museum of the USAF is one of only two examples that survive today.

Twin-engine advanced trainer.