Martin XB-48

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B-48

Type	Bomber
Manufacturer	Glenn L. Martin Company
Maiden flight	1947-06-22
Status	Cancelled in 1948
Number built	2
Unit cost	US$11.5 million for the program^[1]

The Martin XB-48 was a medium jet bomber developed in the mid-1940s which never saw production or active duty. Only two prototypes were built.

In 1944 the U.S. War Department was aware of aviation advances in Germany and issued a requirement for a range of designs for medium bombers weighing from 80,000 to more than 200,000 pounds. Other designs resulting from this competition, sometimes named the class of '45, included the North American XB-45 and the Convair XB-46. Production orders finally went to the B-45 Tornado and even this airplane only served for a couple of years before again being replaced by the much more modern B-47 Stratojet.

In retrospect, the class of '45 were transitional aircraft combining the power of turbojets with the aeronautical knowledge of world War II. The XB-48 was no exception, as its round fuselage and unswept wings show a distinct patronage from the earlier Martin B-26 medium bomber. Still, where the B-26 had enough thrust with two massive 18-cylinder radial engines, the XB-48 needed no less than 6 of the new jet engines. Although the pictures make it look like the aircraft has three engine gondolas under each wing, the jet engines were actually clustered in two flat three-engined gondolas with an intricate system of air canals between the engines providing cooling. At the time of the XB-48's design, jet propulsion was clearly still in is infancy.

[edit] Specifications (B-26G)

Data from 世界の駄作機 2^[2]

General characteristics

Crew: 3
Length: 26.1m ()
Wingspan: 33.0m ()
Height: ()
Empty weight: 26,578 kg ()
Loaded weight: 46,539 kg ()
Powerplant: 6× Allison J35 turbojets, 1,700 kg () each

Performance

Maximum speed: 830 km
Combat radius: 1,280 km ()

Armament

Guns: 2 × .50 (12.7 mm) M7 machine guns in tail turret
Bombs: 1 × 20,000 lb (9,980 kg) or 36 × 250 lb (113 kg)

[edit] References

^ Knaack, MS (1988). Post-World War II bombers, 1945-1973. Office of Air Force History. ISBN 0-16-002260-6.
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