The B-2 might look futuristic, but the basic design isn't new at all, the same manufacturer Northrop did two very similar designs just after world war two, the propeller driven B-35 and the jet driven B-49.
Northrop B-35
The B-35 was America's first attempt at an all-wing heavy bomber. In the darkest days of World War II, when it
appeared that Nazi Germany might well conquer Great Britain and the Soviet Union, the Army Air Forces saw the
need for a large bomber with intercontinental range. Such a plane, based in the United States, must be able to cross
the Atlantic and hit Germany with a large bomb load. The XB-35 was required to carry a 10,000-pound bomb load
a distance of 10,000 miles. Four Pratt & Whitney R-4360 engines mounted internally, close to the leading edge.
Each engine drove a pair of counter-rotating four-bladed propellers by means of a long extension shaft and a complex
gearbox. The XB-35's first flight, on June 25, 1946, was a success. But that was about the only trouble-free flight the
bomber was ever to have. Numerous equipment failures had already delayed the plane's development by more than a year.
Only three B-35s were completed. The remainder of the initial test models were converted to jet power.
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Northrop B-49
With the wing development program falling farther behind schedule daily, the AAF entered into negotiations with Northrop during the summer of 1944 about the possibility of replacing the troublesome R-4360 engines with (General Electric designed) Chevrolet built TG-180-A7 jet engines and designated YB-49. The final YB-49 configuration was powered by eight Allison J-35-A-15 engines developing 3,750 pounds of static thrust.
Still without a production contract, Northrop explored the possibility of producing a B-49 derived photo-reconnaissance aircraft designated YRB-49. To make room for photographic equipment, extra fuel and flash bombs, the six engined aircraft carried two jet engines in pods outboard of the main landing gear under the wings.
Slower, shorter ranged than its progenitor, and not wanted by the USAF signaled the end of flying wing bombers in the U.S. until the advent of the Northrop B-2 bomber. No examples of the XB-35/YB-49 family exist today. The last YRB-49 was scrapped by December 1953.
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Northrop B-2
The first B-2 was publicly displayed on 22 November 1988, when it was rolled out of its hangar at Air Force Plant 42, Palmdale, California, where it was built. Its first public flight was on 17 July 1989. The B-2 Combined Test Force, Air Force Flight Test Center, Edwards Air Force Base, California, is responsible for flight testing the engineering, manufacturing and development aircraft.
The original procurement of 132 aircraft was later reduced to 75 in the late 1980s. In his 1992 State of the Union Address, President George H.W. Bush announced total B-2 production would be limited to 20 aircraft, with a total inventory of 21 by upgrading the first test aircraft to B-2A Block 30 standard. This reduction was largely a result of the disintegration of the Soviet Union, which effectively rendered void the Spirit's primary mission.
The cost of the B-2 program in 1994 dollars was reported at $737 million per plane; however, the total cost of the program with development, spares, and facilities averaged over $2.1 billion per plane as of 1997 according to the B-2 program office
The first operational aircraft, christened Spirit of Missouri, was delivered on December 17, 1993
Related Links:
http://www.airbornegrafix.com/HistoricAircraft/FlyingWings/XB35.htm
http://www.richard-seaman.com/Aircraft/AirShows/Edwards2005/B2/index.html
http://en.wikipedia.org/wiki/B-2_Spirit
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