Named after bomber pioneer Billy Mitchell, the North American B-25 Mitchell was one of the best medium bombers of the war, serving in all theaters the US was involved in although it will be best remembered for the Doolittle raid against Tokyo in April 1942 in which 16 B-25s flew from the deck of the USS Hornet to bomb the japanese capital. Designed by a team led by Lee Atwood and Ray Rice, it was slightly gull-winged, possessed good flight characteristics and was well-liked by those who flew it not least on account on its ruggedness and dependability; not surprisingly, it became the most widely produced twin-engined US bomber of the war. B-25s were employed early in the war in the South Pacific and North Africa and later over Europe alongside it's contemporary, the B-26, in the tactical bombing role and as such, many variants were developed throughout the conflict featuring various combinations of armaments which included a 75-mm gun in one particular gunship variant. Besides serving with the USAAF, they also flew with distinction with other Allied air forces including those of Australia, Brazil, China, France, Italy (Co-Belligerent), Mexico, the Netherlands, the UK, and the USSR.

The private-venture NA-40 prototype was first flown on 19 August 1940 and was followed by the production B-25A with self-sealing fuel tanks and increased armor protection. The Doolittle raiders flew modified B-25Bs, stripped of any unnecessary weight and guns although standard units actually had greater defensive armament than the preceeding version. Weight and fuel was increased in the B-25C/D (same aircraft built in different plants) while the B-24G featured a nose-mounted 75-mm field gun for use as a gunship in the Pacific, it would be the precursor to a concept which would reach its zenith in the Vietnam War. The B-24H upped the ante with the incredible number of 14 .50-in guns as well. The final and most-produced variant was the B-24J which returned to the standard bomber configuration although a number were also armed as gunships with up to 18 .50-in guns and a solid nose. Other roles included photo-reconnaissance (F-10) and US Navy patrol bombers (PBJ), the last Mitchell trainer was not retired from the USAF until 1959. RAF equivalents were the Mitchell Mk. I (B-25B), Mk. II (B-25C/D) and Mk. III (B-25J).