B-25J Mitchell Specifications:
- Length: 52 ft. 11 in.
- Wingspan: 67 ft. 6 in.
- Height: 17 ft. 7 in.
- Wing Area: 610 sq. ft.
- Empty Weight: 21,120 lbs.
- Loaded Weight: 33,510 lbs.
- Crew: 6
- Power Plant: 2 × Wright R-2600 Cyclone radials, 1,850 hp
- Combat Radius: 1,350 miles
- Max Speed: 275 mph
- Ceiling: 25,000 ft.
- Guns: 12-18 × .50 in (12.7 mm) M2 Browning machine guns
- Bombs: 6,000 lbs. max. or 8 x 5" rockets & 3,000 lbs. bombs
B-25 Mitchell - Development:
In 1936, North American Aviation began work on its first twin-engine military design. Dubbed the NA-21 (later NA-39), this project ultimately evolved into the XB-21. In testing against the Douglas B-18 Bolo, the design performed well but a high price tag led the US Army Air Corps to pass on the aircraft. Utilizing the lessons learned from the project, North American moved forward with a new design for a medium bomber which was dubbed the NA-40. Among the improvements incorporated in the NA-40 was the use of two Wright R-2600 Cyclone engines.
Seeking to take advantage of Britain and France's need for a medium bomber during the early days of World War II, North American originally intended the NA-40 to be built for export. Both countries elected to move forward with a different aircraft and North American submitted an improved NA-40B design to the USAAC for evaluation as a medium bomber. A prototype of the aircraft first flew on August 19, 1940. As the USAAC had an immediate need for a medium bomber, the type was accepted without additional test versions being built.
B-25 Mitchell - Design & Production:
Designated B-25 Mitchell, the aircraft was named for Major General Billy Mitchell. Featuring a distinctive twin tail, early variants of the B-25 also incorporated a "greenhouse"-style nose which contained the bombardier's position. They also possessed a tail gunner position at the rear of the aircraft. This was eliminated in the B-25B while a manned dorsal turret was added along with a remotely operated ventral turret. Around 120 B-25Bs were built with some going to the Royal Air Force as the Mitchell Mk.I. Improvements continued and the first type to be mass-produced was the B-25C/D.
This variant increased the aircraft's nose armament and saw the addition of improved Wright Cyclone engines. Over 3,800 B-25C/Ds were produced and many saw service with other Allied nations. As the need for effective ground support/attack aircraft increased, the B-25 frequently saw field modifications to fulfill this role. Acting on this, North American devised the B-25G which increased the number of guns on the aircraft and included the mounting of a 75 mm cannon in a new solid nose section. These alterations were refined in the B-25H.
In addition to a lighter 75 mm cannon, the B-25H mounted four .50-cal. machine guns below the cockpit as well as four more in cheek blisters. The aircraft saw the return of the tail gunner position and the addition of two waist guns. Capable of carrying 3,000 lbs. of bombs, the B-25H also possessed hard points for eight rockets. The final variant of the aircraft, the B-25J, was a cross between the B-25C/D and the G/H. It saw the removal of the 75 mm gun and the return of the open nose, but the retention of the machine gun armament. Some were built with a solid nose and an increased armament of 18 machine guns.
B-25 Mitchell - Operational History:
The aircraft first came to prominence in April 1942 when Lieutenant Colonel James Doolittle used modified B-25Bs in his raid on Japan. Flying from the carrier USS Hornet on April 18, Doolittle's 16 B-25s struck targets in Tokyo, Yokohama, Kobe, Osaka, Nagoya, and Yokosuka before flying on to China. Deployed to most theaters of the war, the B-25 saw service in the Pacific, North Africa, China-India-Burma, Alaska, and the Mediterranean. Though effective as a level medium bomber, the B-25 proved particularly devastating in Southwest Pacific as a ground attack aircraft.
Modified B-25s routinely conducted skip bombing and strafing attacks against Japanese ships and ground positions. Serving with distinction, the B-25 played key roles in Allied victories such as the Battle of the Bismarck Sea. Employed throughout the war, the B-25 was largely retired from frontline service at its conclusion. Though known as a forgiving aircraft to fly, the type did cause some hearing loss problems among crews due to engine noise issues. In the years after the war, the B-25 was used by a number of foreign nations.