https://en.wikipedia.org/wiki/North_American_B-25_Mitchell
The North American B-25 Mitchell is an American twin-engine, medium bomber
manufactured by North American Aviation (NAA).
The design was named in honor of Major General William "Billy" Mitchell, a
pioneer of U.S. military aviation. Used by many Allied air forces, the B-25
served in every theater of World War II and after the war ended many remained in
service, operating across four decades. Produced in numerous variants, nearly
10,000 Mitchells rolled from NAA factories.[1] These included a few limited
models, such as the United States Marine Corps' PBJ-1 patrol bomber and the
United States Army Air Forces' F-10 reconnaissance aircraft and AT-24 trainers.
The Air Corps issued a circular (Number 38-385) in March 1938 describing the
with a range of 1,200 mi (1,900 km) at more than 200 mph (320 km/h).[2] Those
performance specifications led NAA[3] to submit their NA-40 design. The NA-40
had benefited from the North American XB-21 (NA-39) of 1936, which was the
company's partly successful design for an earlier medium bomber that had been
initially accepted and ordered, but then cancelled. However, the company's
experience from the XB-21 contributed to the design and development of the
NA-40. The single NA-40 built flew first at the end of January 1939. It went
through several modifications to correct problems. These improvements included
fitting 1,600 hp (1,193 kW) Wright R-2600 "Twin Cyclone" radial engines, in
March 1939, which solved the lack of power.
In March 1939, North American delivered the substantially redesigned and
improved NA-40 (as NA-40B) to the United States Army Air Corps for
evaluation.[2] It was in competition with other manufacturers' designs (Douglas
7B, Stearman X-100, and the Martin Model 167F)[4] but failed to win orders. The
aircraft was originally intended to be an attack bomber for export to the United
Kingdom and France, both of which had a pressing requirement for such aircraft
in the early stages of World War II. However, the French had already opted for a
revised Douglas 7B (as the DB-7). Unfortunately, the NA-40B was destroyed in a
crash on 11 April 1939 while undergoing testing. Although the crash was not
considered due to a fault with the aircraft design, the Army ordered the DB-7 as
the A-20.
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)[7] NAA used the NA-40B design to develop the NA-62, which
competed for the medium bomber contract. There was no YB-25 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".
Role
Medium bomber
National origin
United States
Manufacturer
North American Aviation
First flight
19 August 1940
Introduction
1941
Retired
1979 (Indonesia)
Primary users
United States Army Air Forces
Royal Air Force
Soviet Air Force
United States Marine Corps
Number built
9,816[1][a]
Developed from
North American XB-21
Developed into
North American XB-28 Dragon
Asia-Pacific
The majority of B-25s in American service were used in the war against Japan in
Asia and the Pacific. The Mitchell fought from the Northern Pacific to the South
Pacific and the Far East. These areas included the campaigns in the Aleutian
Islands, Papua New Guinea, the Solomon Islands, New Britain, China, Burma and
the island hopping campaign in the Central Pacific. The aircraft's potential as
a ground-attack aircraft emerged during the Pacific war. The jungle environment
reduced the usefulness of medium-level bombing, and made low-level attack the
best tactic. Using similar mast height level tactics and skip bombing, the B-25
proved itself to be a capable anti-shipping weapon and sank many enemy sea
vessels of various types. An ever-increasing number of forward firing guns made
the B-25 a formidable strafing aircraft for island warfare. The strafer versions
were the B-25C1/D1, the B-25J1 and with the NAA strafer nose, the J2 sub-series.
In Burma, the B-25 was often used to attack Japanese communication links,
especially bridges in central Burma. It also helped supply the besieged troops
at Imphal in 1944. The China Air Task Force, the Chinese American Composite
Wing, the First Air Commando Group, the 341st Bomb Group, and eventually, the
relocated 12th Bomb Group, all operated the B-25 in the China Burma India
Theater (CBI). Many of these missions involved battle field isolation,
interdiction and close air support.
USAAF
The B-25B first gained fame as the bomber used in the 18 April 1942 Doolittle
Raid, in which 16 B-25Bs led by Lieutenant Colonel Jimmy Doolittle 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 to be inviolable by enemy forces. Although the
amount of actual damage done was relatively minor, it forced the Japanese to
divert troops for home defense for the remainder of the war.
The raiders took off from the carrier USS Hornet and successfully bombed Tokyo
and four other Japanese cities without loss. Fifteen of the bombers subsequently
crash-landed en route to recovery fields in eastern China. These losses were the
result of the task force being spotted by a Japanese vessel, 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 B-25 bomber landed intact, in Siberia 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.
Flight characteristics
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 was 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
rudder, causing the aircraft to "crab" sideways across the sky.
Empire State Building crash
https://en.wikipedia.org/wiki/B-25_Empire_State_Building_crash
At 9:40 on Saturday, 28 July 1945, a USAAF B-25D crashed in thick fog into the
north side of the Empire State Building between the 79th and 80th floors.
aircraft, including the pilot, Colonel William F. Smith.[47] Betty Lou Oliver,
an elevator attendant, survived the impact and the subsequent fall of the
elevator cage 75 stories to the basement.[48]
French general Philippe Leclerc was aboard his North American B-25 Mitchell,
1947, killing everyone on board.
Specifications (B-25H)
General characteristics
Crew: 5 (one pilot, navigator/bombardier, turret gunner/engineer, radio
operator/waist gunner, tail gunner)
Length: 52 ft 11 in (16.13 m)
Wingspan: 67 ft 7 in (20.60 m)
Height: 16 ft 4 in (4.98 m)
Empty weight: 19,480 lb (8,855 kg)
Max. takeoff weight: 35,000 lb (15,910 kg)
engine, 1,700 hp (1,267 kW) each
Performance
Maximum speed: 272 mph (237 kn, 438 km/h) at 13,000 ft (3,960 m)
Cruise speed: 230 mph (200 knots, 370 km/h)
Range: 1,350 mi (1,174 nmi, 2,174 km)
Service ceiling: 24,200 ft (7,378 m)
Armament
Hardpoints: 2,000 lb (900 kg) ventral shackles to hold one external Mark 13
torpedo[46]
Rockets: racks for eight 5 in (127 mm) high velocity aircraft rockets (HVAR)
Bombs: 3,000 lb (1,360 kg) bombs
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