The SN-J and T-6: “Texan” (U.S. Army Air Corps), SN-J (U.S. Navy) and “Harvard” & “Yale” (British Commonwealth). Also known as “Pilot Maker” and “Old Growler” and “Window Breaker” and “J-Bird” (U.S. Navy SNJ). The Texan was designed initially by North American as an advanced trainer for U.S. Army Air Corps and U.S. Navy pilots, and was taken up by the British Royal Air Force and Royal Canadian Air Force pilots. In all during its long career, it was flown by as many as 59 militaries worldwide and employed in many ways. It was fitted with a Pratt & Whitney R-1340 Wasp engine (the ungeared engine causes the propeller tips to spin at near speed-of-sound causing a mini-sonic boom or “sonic snap”). For gunnery practice (or use in combat by some militaries) it could be armed with up to four .30 cal. machine guns: one atop the cowl firing through the propeller arc, one in each wing, and one on a flexible rear-facing mount). While designed as a trainer, versions of the aircraft were flown by a number of militaries in combat roles and armed with machine guns, bombs and rockets. The U.S. Army Air Corps flew ten that were armed as A-27 attack trainers originally built for shipment to Thailand. It has a hand-operated auxiliary starter and a foot step for the ground crew on the port side of the cowling. There are plexiglass windows atop each wing above the landing gear for the red-marked mechanical landing gear indicators for the pilot. The G version was fitted with a steerable tailwheel.