North American B-25 Mitchell

The North American B-25 Mitchell is a medium-bomber plane.

Characteristics
The Air Corps issued a specification for a medium bomber in March 1939 that was capable of carrying a payload of 2,400 lb (1,100 kg) over 1,200 mi (1,900 km) at 300 mph (480 km/h) North American Aviation used its NA-40B design to develop the NA-62, which competed for the medium bomber contract. No YB-25 was available for prototype service tests. In September 1939, the Air Corps ordered the NA-62 into production as the B-25, along with the other new Air Corps medium bomber, the Martin B-26 Marauder "off the drawing board".

Early into B-25 production, NAA incorporated a significant redesign to the wing dihedral. The first nine aircraft had a constant-dihedral, meaning the wing had a consistent, upward angle from the fuselage to the wingtip. This design caused stability problems. "Flattening" the outer wing panels by giving them a slight anhedral angle just outboard of the engine nacelles nullified the problem and gave the B-25 its gull wing configuration. Less noticeable changes during this period included an increase in the size of the tail fins and a decrease in their inward tilt at their tops.

NAA continued design and development in 1940 and 1941. Both the B-25A and B-25B series entered USAAF service. The B-25B was operational in 1942. Combat requirements led to further developments. Before the year was over, NAA was producing the B-25C and B-25D series at different plants. Also in 1942, the manufacturer began design work on the cannon-armed B-25G series. The NA-100 of 1943 and 1944 was an interim armament development at the Kansas City complex known as the B-25D2. Similar armament upgrades by U.S-based commercial modification centers involved about half of the B-25G series. Further development led to the B-25H, B-25J, and B-25J2. The gunship design concept dates to late 1942 and NAA sent a field technical representative to the SWPA. The factory-produced B-25G entered production during the NA-96 order followed by the redesigned B-25H gunship. The B-25J reverted to the bomber role, but it, too, could be outfitted as a strafer.

NAA manufactured the greatest number of aircraft in World War II, the first time a company had produced trainers, bombers, and fighters simultaneously (the AT-6/SNJ Texan/Harvard, B-25 Mitchell, and the P-51 Mustang). It produced B-25s at both its Inglewood main plant and an additional 6,608 aircraft at its Kansas City, Kansas, plant at Fairfax Airport.

Flight characteristics
The B-25 was a safe and forgiving aircraft to fly. With one engine out, 60° banking turns into the dead engine were possible, and control could be easily maintained down to 145 mph (230 km/h). The pilot had to remember to maintain engine-out directional control at low speeds after takeoff with rudder; if this maneuver were attempted with ailerons, the aircraft could snap out of control. The tricycle landing gear made for excellent visibility while taxiing. The only significant complaint about the B-25 was the extremely high noise level produced by its engines; as a result, many pilots eventually suffered from varying degrees of hearing loss.

The high noise level was due to design and space restrictions in the engine cowlings, which resulted in the exhaust "stacks" protruding directly from the cowling ring and partly covered by a small triangular fairing. This arrangement directed exhaust and noise directly at the pilot and crew compartments.

Durability
The Mitchell was an exceptionally sturdy aircraft that could withstand tremendous punishment. One B-25C of the 321st Bomb Group was nicknamed "Patches" because its crew chief painted all the aircraft's flak hole patches with the bright yellow zinc chromate primer. By the end of the war, this aircraft had completed over 300 missions, had been belly-landed six times, and had over 400 patched holes. The airframe of "Patches" was so distorted from battle damage that straight-and-level flight required 8° of left aileron trim and 6° of right rudder, causing the aircraft to "crab" sideways across the sky.

History
The bomber was only seen during last portion of the movie, where they were first seen being modified for the upcoming Doolittle Raid, then being tested with said modifications for use on aircraft-carriers, before eventually taking the mission for real. Capt. Rafe McCawley and Capt. Danny Walker each piloted one Mitchell, and like in real life, both crashed in a Japanese-controlled portion of China (though Danny somewhat crashed on purpose).

Trivia

 * Danny also strafed several Japanese soldiers in his Mitchell-bomber, partly to protect Rafe, but in truth, none of the raiders did something like this.