BT Series
; BT-9 :Basic Trainer with 400hp Wright R-975-7 Whirlwind and new canopy. Dangerous stall resulted in a variety of unsuccessful fixes. 42 built. ;BT-9A :Armed BT-9 with one cowl gun and one rear flexible gun, and modified canopy. 40 built. ;BT-9B :Minor changes from BT-9, unarmed. 117 built. 1 modified as sole BT-9D which was modified as a prototype for BT-14 with new outer wing panels and other alterations. ;BT-9C :Wright R-975-7, similar to the BT-9A with minor changes. 66 built ;BT-9D :One prototype only, Intermediate step in development of the BT-14. ;Y1BT-10 :600hp Pratt & Whitney R-1340-41. First aircraft of batch of BT-9C completed as Y1BT-10. ;BT-10 :Production version of Y1BT-10 - cancelled ;BT-14 :lengthened all metal fuselage and new canopy, Pratt & Whitney R-985-25, 251 built. ;BT-14A :27 BT-14s were re-engined with 400 hp (298 kW) Pratt & Whitney R-985-11.BC Series
;North American BC-1 :Basic Combat trainer version initial production version with 600hp R-1340-47 engine, Early examples had round rudder, later examples had square bottom rudder. 177 built ;BC-1A :New longer