The Martin XB-33 Super Marauder was a proposed

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

American bomber aircraft. It was designed by the

Glenn L. Martin Company The Glenn L. Martin Company—also known as The Martin Company from 1957-1961—was an American aircraft and aerospace manufacturing company founded by aviation pioneer Glenn L. Martin, and operated between 1917-1961. The Martin Company produce ...

as the Martin Model 190 and was a high-altitude derivative of the company's

B-26 Marauder The Martin B-26 Marauder is an American twin-engined medium bomber that saw extensive service during World War II. The B-26 was built at two locations: Baltimore, Maryland, and Omaha, Nebraska, by the Glenn L. Martin Company. First used in ...

. Two different designs were developed, first as a twin-engined aircraft and then as a four-engined aircraft. The four-engined version was ordered by the

United States Army Air Forces The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...

, but the program was cancelled before any aircraft were built.

Design and development

XB-33

The first version of the B-33 design, the XB-33, was a twin-tailed medium bomber with two

Wright R-3350 The Wright R-3350 Duplex-Cyclone is an American twin-row, supercharged, air-cooled, radial aircraft engine with 18 cylinders displacing nearly . Power ranged from 2,200 to over 3,700 hp (1,640 to 2,760 kW), depending on the model. ...

engines and pressurised crew compartments; its design began in

1940 A calendar from 1940 according to the Gregorian calendar, factoring in the dates of Easter and related holidays, cannot be used again until the year 5280. Events Below, the events of World War II have the "WWII" prefix. January *January ...

. It would carry around 4,000 lb (1,814 kg) of bombs. Soon after design of the XB-33 began it became clear that a twin-engined aircraft would not achieve the performance requested by the army. The company moved on to developing a larger four-engined design, the XB-33A.

XB-33A

Following the abandonment of the original twin-engined design, the company continued to design a larger four-engined aircraft, and two prototypes were ordered by the USAAF as the XB-33A; its bombload was to have been 12,000 lb (5,443 kg), as much as that of the

B-24 Liberator The Consolidated B-24 Liberator is an American heavy bomber, designed by Consolidated Aircraft of San Diego, California. It was known within the company as the Model 32, and some initial production aircraft were laid down as export models d ...

, the heaviest US bomber flown in combat prior to the

B-29 The Boeing B-29 Superfortress is an American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the B-17 Fl ...

. The original XB-33 design was to have been powered by the R-3350, the redesigned XB-33A was to have used

Wright R-2600 The Wright R-2600 Cyclone 14 (also called Twin Cyclone) is an American radial engine developed by Curtiss-Wright and widely used in aircraft in the 1930s and 1940s. History In 1935, Curtiss-Wright began work on a more powerful version of their ...

engines. The main reason for this was the demand for R-3350s for the B-29, one of the most highly valued projects of the Army Air Forces. On January 17, 1942, the USAAF placed an order for 400 B-33As, to be built at the government-owned plant in

Omaha, Nebraska Omaha ( ) is the largest city in the U.S. state of Nebraska and the county seat of Douglas County, Nebraska, Douglas County. Omaha is in the Midwestern United States on the Missouri River, about north of the mouth of the Platte River. List of ...

, operated by Martin. On November 25, 1942, the project was cancelled to allow the Omaha plant to concentrate on manufacturing B-29s.

Variants

;XB-33 :Prototype medium bomber powered by two 1,800 hp (1,343 kW)

R-3350 The Wright R-3350 Duplex-Cyclone is an American twin-row, supercharged, air-cooled, radial aircraft engine with 18 cylinders displacing nearly . Power ranged from 2,200 to over 3,700 hp (1,640 to 2,760 kW), depending on the model. De ...

engines, two ordered and cancelled.Andrade 1979, p 51 ;XB-33A :Prototype medium bomber powered by four 1,800 hp (1,343 kW) R-2600-15 engines, two ordered and cancelled. ;B-33A Super Marauder :Production variant of XB-33A, 400 ordered and cancelled.

Specifications (B-33A, as designed)

References

Notes

Bibliography

Encyclopedia of American Aircraft
* {{USAF bomber aircraft 1940s United States bomber aircraft B-33 Super Marauder Four-engined piston aircraft