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"Stealth Bomber" redirects here. For stealth aircraft in general, see Stealth aircraft.
| B-2 Spirit | |
|---|---|
 |
|
| A U.S. Air Force B-2 Spirit over the Pacific Ocean in May 2006. | |
| Role | Strategic stealth bomber |
| National origin | United States |
| Manufacturer | Northrop Corporation Northrop Grumman |
| First flight | 17 July 1989 |
| Introduction | April 1997 |
| Status | In service |
| Primary user | United States Air Force |
| Produced | 1988-2000 |
| Number built | 21[1][2] |
| Program cost | US$44.75 billion (through 2004)[3] |
| Unit cost | $737 million (1997 approx. flyaway cost)[3] |
Development originally started under the "Advanced Technology Bomber" (ATB) project during the Carter administration, and its performance was one of the reasons for his cancellation of the B-1 Lancer. ATB continued during the Reagan administration, but worries about delays in its introduction led to the reinstatement of the B-1 program as well. Program costs rose throughout development. Designed and manufactured by Northrop Grumman with assistance from Boeing, the cost of each aircraft averaged US$737 million (in 1997 dollars).[3] Total procurement costs averaged $929 million per aircraft, which includes spare parts, equipment, retrofitting, and software support.[3] The total program cost including development, engineering and testing, averaged $2.1 billion per aircraft in 1997.[3]
Because of its considerable capital and operating costs, the project was controversial in the U.S. Congress and among the Joint Chiefs of Staff. The winding-down of the Cold War in the latter portion of the 1980s dramatically reduced the need for the aircraft, which was designed with the intention of penetrating Soviet airspace and attacking high-value targets. During the late 1980s and 1990s, Congress slashed plans to purchase 132 bombers to 21. In 2008, a B-2 was destroyed in a crash shortly after takeoff, and the crew ejected safely.[4] A total of 20 B-2s remain in service with the United States Air Force.
The B-2 is capable of all-altitude attack missions up to 50,000 ft, with a range of more than 6,000 nautical miles unrefuelled and over 10,000 nautical miles with one refueling. Though originally designed primarily as a nuclear bomber, it was first used in combat to drop conventional bombs on Serbia during the Kosovo War in 1999, and saw continued use during the wars in Iraq and Afghanistan.[5]
Contents
Development
Origins
In the mid-1970s, the search for a new U.S. strategic bomber to replace the Boeing B-52 Stratofortress was underway, to no avail. First the B-70 and then the B-1A were canceled after only a few of each aircraft were built. The B-70 was intended to fly above and beyond defensive interceptor aircraft, only to find these same attributes made it especially vulnerable to surface-to-air missiles (SAMs). The B-1 attempted to avoid SAMs by flying close to the ground to use terrain to mask its radar signature, only to face a new generation of interceptors with look-down/shoot-down capabilities that could attack them from above.[6]By the mid-1970s, it was becoming clear that there was a different way to avoid missiles and intercepts; known today as "stealth"; the concept was to build an aircraft with an airframe that deflected or absorbed radar signals so that little was reflected back to the radar unit. An aircraft having stealth characteristics would be able to fly nearly undetected and could be attacked only by weapons and systems not relying on radar. Although such possibilities existed, such as human observation, their relatively short detection range allowed most aircraft to fly undetected by defenses, especially at night.[7]
In 1974, DARPA requested information from U.S. aviation firms about the largest radar cross-section of an aircraft that would remain effectively invisible to radars.[8] Initially, Northrop and McDonnell Douglas were selected for further development. Lockheed had experience in this field due to developing the Lockheed A-12 and SR-71, which included a number of stealthy features, notably its canted vertical stabilizers, the use of composite materials in key locations, and the overall surface finish in radar-absorbing paint. A key improvement was the introduction of computer models used to predict the radar reflections from flat surfaces where collected data drove the design of a "faceted" aircraft. Development of the first such designs started in 1975 with "the hopeless diamond", a model Lockheed built to test the concept.[9]
Plans were well advanced by the summer of 1975, when DARPA started the Experimental Survivability Testbed (XST) project. Northrop and Lockheed were awarded contracts in the first round of testing. Lockheed received the sole award for the second test round in April 1976 leading to the Have Blue program.[10]
ATB program
By 1976, these programs progressed to where a long-range strategic stealth bomber appeared viable. President Carter was aware of these developments during 1977, and it appears to have been one of the major reasons the B-1 was canceled.[11] Further studies were ordered in early 1978, by which point the Have Blue platform had flown and proven the concepts. During the 1980 presidential election in 1979, Ronald Reagan repeatedly stated that Carter was weak on defense, and used the B-1 as a prime example. In return, on 22 August 1980, the Carter administration publicly disclosed that the United States Department of Defense (DoD) was working to develop stealth aircraft, including a bomber.[12]
The Northrop/Boeing team's ATB design was selected over the Lockheed/Rockwell design on 20 October 1981.[13][17] The Northrop design received the designation B-2 and the name "Spirit". The bomber's design was changed in the mid-1980s when the mission profile was changed from high-altitude to low-altitude, terrain-following. The redesign delayed the B-2's first flight by two years and added about US$1 billion to the program's cost.[12] An estimated US$23 billion was secretly spent for research and development on the B-2 by 1989.[18] MIT scientists helped assess the mission effectiveness of the aircraft under a five-year classified contract during the 1980s.[19]
Secrecy and espionage
For the manufacturing, a former Ford automobile assembly plant in Pico Rivera, California was acquired and heavily rebuilt; the plant's employees were sworn to complete secrecy regarding their work. To avoid the possibility of suspicion, components were typically purchased through front companies, military officials would visit out of uniform, and staff members were routinely subjected to polygraph examinations. The secrecy extended so far that access to nearly all information on the program by both Government Accountability Office (GAO) and virtually all members of Congress itself was severely limited until mid-1980s.[21]
In 1984, a Northrop employee, Thomas Cavanaugh was arrested for attempting to sell classified information to the Soviet Union; the information was taken from Northrop's Pico Rivera, California factory.[22] Cavanaugh was eventually sentenced to life in prison and released on parole in 2001.
The B-2 was first publicly displayed on 22 November 1988 at Air Force Plant 42, Palmdale, California, where it was assembled. This viewing was heavily restricted, and guests were not allowed to see the rear of the B-2. However, Aviation Week editors found that there were no airspace restrictions above the presentation area and took photographs of the aircraft's then-secret planform and suppressed engine exhausts from the air, to the USAF's disappointment. The B-2's first public flight was on 17 July 1989 from Palmdale.[23]
In October 2005, Noshir Gowadia, a design engineer who worked on the B-2's propulsion system, was arrested for selling B-2 related classified information to foreign countries.[24] On 9 August 2010, Gowadia was convicted in the United States District Court for the District of Hawaii on 14 of 17 charges against him.[25] On 24 January 2011, Gowadia was sentenced to 32 years in prison.[26]
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