10/31/2011. Ordered on February 21, 1939, the NA-57 was an improved version of the basic NA-16 trainer series and similar to the USAAC NA-23
BT-9B. It had a fixed tail wheel landing gear and was powered by a 400 hp Wright R-975 Whirlwind radial engine. The French AF bought 200 aircraft (c/n 57-1253 to 57-1452), these were operated in the Et2 (Entrainement biplace, two-seat trainer) category, while the French Navy obtained thirty aircraft (c/n 57-1518 to 57-1547), which were operated in the P2 (Perfectionement biplace, advanced two-seat) category.