Introduction
The B-25 twin engined bomber was built by North American Aviation in Los Angeles. The name “B-25 Mitchell” was in honor of Major General Billy Mitchell, a pioneer in military aviation.
There were 9,816 B-25s produced by NAA in various configurations. They saw action in every theater of World War II by several Allied Air Forces.
The B-25 was a safe and forgiving aircraft. With one engine feathered, banking turns even up to 60 degrees toward the “dead” engine was easily maintained.
The tricycle made for excellent visibility while taxiing. The only complaint was the excessive noise from the engine. This was of course, in the days before pilot hearing protection.
Design and Development
In March of 1938, the United States Army Air Force put out a bid for a medium bomber capable of carrying 1,200 pounds and able to fly 1,200 statue miles (mi) with a speed of 200 miles per hour (mph).
NAA had in 1936, designed the XB-21 which the Army Air Force had ordered and then cancelled.
NAA XB-21
However this experience led to a better design using 1,600 horse power (hp) Wright 2600 Twin Cyclone radial engines. The major design changes were tricycle landing gear, and twin rudders. The newer design was named NA-40.
NAA XB-40
A year later, the United States Army Air Force started evaluating the contestants. North American entered the XB-40 in competition against the Douglas 7B, Stearman X-100 and Martin Model 167F.
NAA lost out to the Douglas 7B. The main reason Douglas Aircraft was triumphant, the USAAC was looking for an “attack” bomber and the XB-40 was not designed for that purpose.
However the USAAC in the same year of 1939, put out a new bid for a true medium twin bomber bomber. The Specs were twice the payload (2,400 pounds),range of 1,200 mi and a speed of 300 mph.
The NAA NA-40 again lost out to Douglas Aircraft’s A-20. Once more the design experience help NAA advance their design to the NA-62. Further design work on the wing dihedral. (meaning the wing from wing root to the wing tip sloped upwards).
However this caused stability problems. NAA engineers corrected this situation by giving outer panels a slight counter twist outboard of the engine nacelles thus giving the B-25 a gull wing configuration.
Other less noticeable changes was the increase of the size of the tail fins and decrease of their slope.
NAA continued design improvements staring in 1940 through 1944 with models B-25A thru B-25J2. Later in 1952 the TB-25L was built for USAF reciprocal engines pilot training.
North American B-25
Operational History
Asia-Pacific Theater
The most famous incident involving the B-25 was Jimmy Doolittle’s led raid on Tokyo. This occurred on 18 April 1942.
The uniqueness of this raid was that the B-25 did not take off from a land base, say one in China, but was launched for the aircraft carrier USS Hornet.
Sixteen B-25 Mitchells left the USS Hornet on a one-way bombing run over Tokyo. Fifteen of the sixteen B-25s crash landed short of their recovery field in China. The single B-25 that did land , landed in USSR and was interned.
The reason for all the losses was, the Hornet was spotted by the a Japanese fishing boat about 170 mi short of the launch point. So fuel starvation and bad weather were the main causes as the B-25s had to launch earlier then was planned.
However 69 out of the 80 crew members survived the raid and made it back to friendly lines. Although very minor damaged was done on the Tokyo raid, the psychological effect on both sides was the major effect of this raid.
The Japanese, who felt totally secure because of their leaders boasting, now felt violable as military forces had to be redirected from various campaigns to guard against any future intrusions by the Americans.
On the American side this was a great victory, the first since the Pearl Harbor attack four months earlier.
The B-25 was used primarily in the Asia-Pacific theater as a ground attack aircraft. The jungle environment negated the use as medium bomber.
Instead the aircraft was an excellent forward attack aircraft with ever increasing number machine guns in the nose through the years of the war.
The B-25 also was very adapt at “skip bombing” on the ocean and sank many Japanese ships. Besides the strafing and skip bombing, it could haul supplies for besieged troops in the Burma-China theater in 1940’s.
As the war progressed, previously Japanese occupied islands were taken and the B-25 operated against targets in Indochina, Formosa and Kyushu.
Led by Lieutenant General George Kenney, the Far East Air force devastated Japanese targets in the Southwest Pacific Theater from 1944-1945, pushing the Japanese back to their homeland island.
The shortest raid that B-25s were on was when the United States had captured Saipan and performed raids against the Japanese on Guam and Tinian.
Since the United States was “island hopping”, that is, by passing less important Japanese held islands, B-25s used these enemy held islands for bombing practice.
Middle East, Italy and Europe
The first B-25s arrived in Egypt in October 1942. They took up operations against Axis airfields, motorized columns and ground support in the Second Battle of El Alamein.
As the campaign advanced in North Africa which the B-25 was part of. They also played a large role in knocking out roads and rail links in Italy, Austria and the Balkans.
Also B-25s conducted “sea sweeps” from the Gulf of Messina to the Aegean Sea.
Europe
Although USAAC B-25s were confined to the Middle East and Mediterranean, the RAF received 900 B-25s to replace Douglas Bostons, Lockheed Venturas, and Vickers Wellington bombers. The Mitchells were used on targets throughout Europe, especially after “D-Day”.
B-25 Mitchell Operators of the Past
Australia – Bolivia – Brazil – Canada – Republic of China – People’s Republic of China – Chile – Colombia – Cuba – Dominican Republic – France – Indonesia – Mexico – Netherlands – Peru – Poland – Spain – Soviet Union – United Kingdom -United States – Uruguay – Venezuela.
Check with your local air museum in your area to visit this fine venerable Warrior.
Tech Specs for the B-25 Mitchell
Wing Span: 67 ft 7 in
Length: 52 ft 11 in
Height: 16 ft 4 in
Weight: 35,000 lbs (MTOW)
Max Speed: 272 mph; Cruise: 230
Ceiling: 24,200 ft
Range: 1,350 sm
Engine: 2/Wright R-2600-92 Twin Cyclone 14 cylinder air-cooled radial engines
Crew: 6
THANKS, FOR READING! I HOPE THIS WAS INFORMATIVE!
