SNJ Texan / USNNorth American SNJ Texan. This airplane was almost certainly the most extensively used trainer of all time, with more than 17,000 airplanes built by North American. One of the earlier numbers of the great North American T 6 trainer family was the AT 6A, used by the United States Army Air Corps as a gunnery trainer from 1941 onwards. The SNJ was the US Navy designation for their aircraft. The SNJ 5 used one 550 hp Pratt &, Whitney R 1340 AN 1 radial