Martin B-57 Canberra

The Martin B-57 Canberra is an American-built, twin jet engine tactical bomber and reconnaissance aircraft that entered service with the United States Air Force (USAF) in 1953. The B-57 was a license-built version of the British English Electric Canberra; the Glenn L. Martin Company later modified the design to produce several different variants.

The Canberra was the first U.S. jet bomber to drop bombs during combat. Its retirement in 1983 ended the era of the tactical bomber that had its beginning with the British World War I De Havilland DH-4 bomber. The three remaining flightworthy WB-57Fs are technically assigned to the NASA Johnson Space Center, next to Ellington Field in Houston, as high-altitude scientific research aircraft, but are also used for testing and communications in the U.S. and Afghanistan.

Development

At the outbreak of the Korean War in 1950, the USAF found itself in dire need of an all-weather interdiction aircraft. The piston-engined Douglas A-26 Invaders were limited to fair weather operations and were in short supply. On 16 September 1950, the USAF issued a request for a jet-powered bomber with a top speed of 630 mph (1,020 km/h), ceiling of 40,000 feet (12,190 m), and range of 1,150 miles (1,850 km). Full all-weather capability and secondary reconnaissance role had to be included in the design. To expedite the process, only projects based on existing aircraft were considered. The contenders included the Martin XB-51, and the North American B-45 Tornado and AJ Savage.

Canberra

Canberra (/ˈkænbrə/ or /ˈkænbərə/) is the capital city of Australia. With a population of 381,488, it is Australia's largest inland city and the eighth-largest city overall. The city is located at the northern end of the Australian Capital Territory (ACT), 280 km (170 mi) south-west of Sydney, and 660 km (410 mi) north-east of Melbourne. A resident of Canberra is known as a "Canberran".

The site of Canberra was selected for the location of the nation's capital in 1908 as a compromise between rivals Sydney and Melbourne, Australia's two largest cities. It is unusual among Australian cities, being an entirely planned city outside of any state, similar to Washington, D.C. in the United States or Brasília in Brazil. Following an international contest for the city's design, a blueprint by the Chicago architects Walter Burley Griffin and Marion Mahony Griffin was selected and construction commenced in 1913. The Griffins' plan featured geometric motifs such as circles, hexagons and triangles, and was centred on axes aligned with significant topographical landmarks in the Australian Capital Territory.

Canberra (disambiguation)

Canberra is the capital city of Australia. It may also refer to:

Places

Maritime

Aviation

List of craters on Mars: A-G

This is a list of craters on Mars. There are hundreds of thousands of impact craters on Mars, but only some of them have names. This list here only contains named Martian craters starting with the letter A – G (see also lists for H – N and O – Z).

Large Martian craters (greater than 60 km in diameter) are named after famous scientists and science fiction authors; smaller ones (less than 60 km in diameter) get their names from towns on Earth. Craters cannot be named for living people, and small crater names are not intended to be commemorative - that is, a small crater isn't actually named after a specific town on Earth, but rather its name comes at random from a pool of terrestrial place names, with some exceptions made for craters near landing sites. Latitude and longitude are given as planetographic coordinates with west longitude.

A

B

C

D

E

F

G

See also

References

External links

B57

B57 or B-57 may be: