North American B-25 Mitchell

A total of 6,608 B-25s were built at North American's [Vous devez être inscrit et connecté pour voir ce lien] plant in [Vous devez être inscrit et connecté pour voir ce lien].

A descendant of the B-25 was the [Vous devez être inscrit et connecté pour voir ce lien], meant to be a high-altitude version of the B-25.

Despite this premise, the actual aircraft bore little resemblance to the Mitchell.

It had much more in common with the [Vous devez être inscrit et connecté pour voir ce lien].

Operational history


The B-25 first gained fame as the bomber used in the 18 April 1942 [Vous devez être inscrit et connecté pour voir ce lien], in which sixteen B-25Bs led by the
legendary [Vous devez être inscrit et connecté pour voir ce lien], attacked mainland Japan four months after the bombing of Pearl Harbor.

The mission gave a much-needed lift in spirits to the Americans, and alarmed the Japanese who had believed their
home islands were inviolable by enemy troops.

While the amount of actual damage done was relatively minor, it forced the Japanese to divert troops for the home
defense for the remainder of the war.

The raiders took off from the carrier [Vous devez être inscrit et connecté pour voir ce lien] and successfully bombed Tokyo and four other Japanese cities without loss.

However, 15 subsequently crash-landed en route to recovery fields in Eastern China.

These losses were the result of the task force being spotted by Japanese fishing vessels forcing the bombers to take off 170 mi (270 km) early, fuel exhaustion, stormy nighttime conditions with zero visibility, and lack of electronic homing aids at the recovery bases.

Only one landed intact; it came down in the [Vous devez être inscrit et connecté pour voir ce lien], where its five-man crew was interned and the aircraft confiscated.

Of the 80 aircrew, 69 survived their historic mission and eventually made it back to American lines.

Following a number of additional modifications, including the addition of [Vous devez être inscrit et connecté pour voir ce lien] windows for the navigator and radio operator, heavier nose armament, and [Vous devez être inscrit et connecté pour voir ce lien] and anti-icing equipment, the B-25C was released to the Army.

This was the second mass-produced version of the Mitchell, the first being the lightly-armed B-25B used by the Doolittle Raiders.

The B-25C and B-25D differed only in location of manufacture: -Cs at [Vous devez être inscrit et connecté pour voir ce lien], -Ds at [Vous devez être inscrit et connecté pour voir ce lien].

A total of 3,915 B-25Cs and -Ds were built by North American during World War II.

Although the B-25 was originally designed to bomb from medium altitudes in level flight, it was used frequently in the [Vous devez être inscrit et connecté pour voir ce lien] (SWPA) on treetop-level [Vous devez être inscrit et connecté pour voir ce lien] and parafrag (parachute-retarded fragmentation bombs) missions against Japanese airfields in [Vous devez être inscrit et connecté pour voir ce lien] and the [Vous devez être inscrit et connecté pour voir ce lien].

These heavily-armed Mitchells, field-modified at [Vous devez être inscrit et connecté pour voir ce lien], by [Vous devez être inscrit et connecté pour voir ce lien] and North American tech rep Dan Fox, were also used on strafing and skip-bombing missions against Japanese shipping trying to re-supply their land-based armies.

Under the leadership of [Vous devez être inscrit et connecté pour voir ce lien], B-25s of the [Vous devez être inscrit et connecté pour voir ce lien] and [Vous devez être inscrit et connecté pour voir ce lien] devastated Japanese targets in the SWPA from 1942 to 1945, and played a significant role in pushing the Japanese back to their home islands.

B-25s were also used with devastating effect in the [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien] and [Vous devez être inscrit et connecté pour voir ce lien] (CBI) theaters.

Because of the urgent need for hard-hitting strafer aircraft, a version dubbed the B-25G was developed, in which the standard-length transparent nose and the bombardier were replaced by a shorter solid nose containing two fixed .50 in
(12.7 mm) [Vous devez être inscrit et connecté pour voir ce lien] and a 75 mm (2.95 in) M4 cannon, one of the largest weapons fitted to an aircraft, similar to the experimental British [Vous devez être inscrit et connecté pour voir ce lien], and German [Vous devez être inscrit et connecté pour voir ce lien] heavy cannon carrying aircraft.

The cannon was manually loaded and serviced by the navigator, who was able to perform these operations without leaving his crew station just behind the pilot.

This was possible due to the shorter nose of the G-model and the length of the M4, which allowed the breech to extend into the navigator's compartment.

The B-25G's successor, the B-25H, had even more firepower. The M4 gun was replaced by the lighter [Vous devez être inscrit et connecté pour voir ce lien], designed specifically for the aircraft.

The 75 mm (2.95 in) gun fired at a muzzle velocity of 2,362 [Vous devez être inscrit et connecté pour voir ce lien] (about 720 [Vous devez être inscrit et connecté pour voir ce lien]).

Due to its low rate of fire (approximately four rounds could be fired in a single [Vous devez être inscrit et connecté pour voir ce lien] run) and relative ineffectiveness against ground targets, as well as substantial recoil, the 75 mm (2.95 in) gun was sometimes removed from both G and H models and replaced with two additional .50 in (12.7 mm) machine guns as a field modification.

The -H also mounted four fixed forward-firing .50 (12.7 mm) machine guns in the nose, four more fixed ones in
forward-firing cheek blisters, two more in the top turret, one each in a pair of new waist positions, and a final pair in a new tail gunner's position.

Company promotional material bragged the B-25H could "bring to bear 10 machine guns coming and four going, in addition to the 75 mm cannon, a brace of eight [Vous devez être inscrit et connecté pour voir ce lien] and 3,000 lb (1,360 kg) of bombs."

The B-25H also featured a redesigned cockpit area, with the top turret moved forward to the navigator's compartment (thus requiring the addition of the waist and tail gun positions),
and a heavily modified cockpit designed to be operated by a single pilot, the co-pilot's station and controls deleted, and the seat cut down and used by the navigator/cannoneer, the radio operator being moved to the aft compartment, operating the waist guns.

A total of 1,400 B-25Gs and B-25Hs were built.

The final version of the Mitchell, the B-25J, looked much like the earlier B, C and D, having reverted to the longer nose.

The less-than-successful 75 mm (2.95 in) cannon was deleted on the J model. Instead, 800 of this version were built with a solid nose containing eight .50 (12.7 mm) machine guns, while other J-models featured the earlier "greenhouse" style nose containing the bombardier's position.

Regardless of the nose style used, all J-models also included two .50 in (12.7 mm) guns in a "fuselage package" located directly under the pilot's station, and two more such guns in an identical package just under the co-pilot's compartment.

The solid-nose B-25J variant carried an impressive total of 18 .50 in (12.7 mm) guns:

eight in the nose, four in under-cockpit packages, two in an upper turret,
two in the waist,
and a pair in the tail.

No other bomber of World War II carried as many guns.

However, the first 555 B-25Js (the B-25J-1-NC production block) were delivered without the fuselage package guns, because it was discovered muzzle blast from these guns was causing severe stress in the [Vous devez être inscrit et connecté pour voir ce lien];
this was cured with heavier fuselage skin patches, while later production runs returned these guns, they were often removed as a field modification for the same reason.

In all, 4,318 B-25Js were built.

The B-25 was a safe and forgiving aircraft to fly. With an engine out, 60° banking turns into the dead engine were possible, and control could be easily maintained down to 145 [Vous devez être inscrit et connecté pour voir ce lien] (230 [Vous devez être inscrit et connecté pour voir ce lien]).

However, the pilot had to remember to maintain engine-out directional control at low speeds after take off with rudder - if this was attempted with ailerons, the aircraft would 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 various degrees of [Vous devez être inscrit et connecté pour voir ce lien].

The Mitchell was also an amazingly sturdy aircraft and could withstand tremendous punishment.

One well-known B-25C of the [Vous devez être inscrit et connecté pour voir ce lien] was nicknamed "Patches" because its crew chief painted all the aircraft's[Vous devez être inscrit et connecté pour voir ce lien] hole patches with high-visibility [Vous devez être inscrit et connecté pour voir ce lien] paint.

By the end of the war, this aircraft had completed over 300 missions, was belly-landed six times and sported over 400 patched holes.

The airframe was so bent, straight-and-level flight required 8° of left [Vous devez être inscrit et connecté pour voir ce lien] trim and 6° of right rudder, causing the aircraft to "crab" sideways across the sky.

An interesting characteristic of the B-25 was its ability to extend range by using one-quarter wing flap settings.

Since the aircraft normally cruised in a slightly nose-high attitude, about 40 gal (150 l) of fuel was below the fuel pickup point and thus unavailable for use.

The flaps-down setting gave the aircraft a more level flight attitude, which resulted in this fuel becoming available, thus slightly extending the aircraft's range.