B-2 Spirit
Encyclopedia
The Northrop Grumman B-2 Spirit (also known as the Stealth Bomber) is an American heavy bomber
with low observable stealth
technology designed to penetrate
dense anti-aircraft defenses
and deploy both conventional and nuclear weapon
s. The bomber has a crew of two and can drop up to eighty 500 lb (226.8 kg)-class JDAM
GPS-guided bombs, or sixteen 2400 lb (1,088.6 kg) B83 nuclear bomb
s. The B-2 is the only aircraft that can carry large air to surface standoff weapons in a stealth configuration.
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). Total procurement
costs averaged $929 million per aircraft, which includes spare parts, equipment, retrofitting, and software support. The total program cost, which includes development, engineering and testing, averaged $2.1 billion per aircraft in 1997.
Because of its considerable capital and operational 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 later 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 early 1990s, the Congress slashed initial plans to purchase 132 bombers to 21. In 2008 one bomber crashed just after takeoff and was destroyed as the crew ejected safely. A total of 20 B-2s remain in service with the United States Air Force
.
Though originally designed primarily as a nuclear bomber, the B-2 was first used in combat to drop conventional bomb
s on Serbia
during the Kosovo War
in 1999, and saw continued use during the wars in Iraq and Afghanistan. B-2s were also used during the 2011 Libyan uprising.
to replace the Boeing B-52 Stratofortress was underway, with nothing to show for it. First the B-70 and then the B-1A were canceled after only small numbers 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 missile
s (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.
However, technology continued to progress throughout. By the mid-1970s it was becoming clear that there was an entirely different way to avoid missiles and intercepts. Known today as "stealth
", the idea was to build an aircraft with an airframe that deflected or absorbed radar signals so that too little was reflected back to the radar unit. An aircraft that was stealthy enough would be able to fly wherever it pleased, and could be attacked only by weapons and systems that did not rely on radar. Although such possibilities exist, notably human observers, ranges were so short that most aircraft could fly right by the defence with impunity, especially at night.
In 1974 DARPA requested information from US aviation firms about the largest radar cross section
of an aircraft where it would remain effectively invisible to radars. Initially, Northrop
and McDonnell Douglas
were selected for further work. Lockheed had experience in this field due to their work on the Lockheed 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 finish in radar absorbing paint. A key improvement was the introduction of computer models that could be used to predict the reflections from flat surfaces and could be used to design a "faceted" aircraft. Work on the first such designs had started in 1975 with "the hopeless diamond", a model built at Lockheed to test the concepts. Improvements quickly followed that allowed designs with more traditional layouts and construction techniques.
These plans were well advanced by the summer of 1975, when DARPA started the Experimental Survivability Testbed (XST) project. Northrop and Lockheed won the first round of testing, and Lockheed was the sole winner of the second round in April 1976. This led to the Have Blue program.
equipment removed, the aircraft would be much simpler and less expensive.
Carter was aware of these developments during 1977, and it appears to have been one of the major reasons the B-1 was canceled. 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 complained that Carter was weak on defence, 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.
The Advanced Technology Bomber (ATB) began in 1979. Full development of the black project
followed. The black program was funded under the code name "Aurora". After the evaluations of the companies' proposals, the ATB competition was reduced to the Northrop
/Boeing
and Lockheed
/Rockwell
teams with each receiving a study contract for further work. Both teams used flying wing designs. Northrop had previous experience from the development of the YB-35
and YB-49
flying wing aircraft. The Northrop design was larger while the Lockheed design included a small tail.
The Northrop/Boeing team's ATB design was selected over the Lockheed/Rockwell design on 20 October 1981. 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. An estimated US$23 billion was secretly spent for research and development
on the B-2 by 1989.
The B-2 was first publicly displayed on 22 November 1988, at Air Force Plant 42
, Palmdale
, California, where it was assembled. This initial viewing was heavily guarded and guests were not allowed to see the rear of the B-2. However, Aviation Week
editors found that there was no ban on overflying the airfield apron/presentation area and, to the chagrin of the USAF, took pictures from above of the aircraft's then-secret planform
and suppressed engine exhausts. The B-2's first public flight was on 17 July 1989 from Palmdale. At the program's peak, approximately 13,000 people were employed at a dedicated plant in Pico Rivera, California
for the aircraft's engineering and portions of its manufacturing.
employee, Thomas Cavanaugh
, was arrested for attempting to sell classified information
to the Soviet Union
, which apparently was smuggled out of the Pico Rivera, California factory. Cavanaugh was eventually sentenced to life in prison and released on parole in 2001.
Noshir Gowadia
, a design engineer who worked on the B-2's propulsion system, was arrested in October 2005 for selling B-2 related classified information to foreign countries. 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. On 24 January 2011, Gowadia was sentenced to 32 years in prison.
had disintegrated, which effectively eliminated the Spirit's primary Cold War mission. Under budgetary pressures and congressional opposition, in his 1992 State of the Union Address
, President George H.W. Bush announced B-2 production would be limited to 20 aircraft. In 1996, however, the Clinton administration, though originally committed to ending production of the bombers at 20 aircraft, authorized the conversion of a 21st bomber, a prototype
test model, to Block 30 fully operational status at a cost of nearly $500 million.
In 1995, Northrop made a proposal to the USAF to build 20 additional aircraft with a flyaway cost
of $566 million each.
The program was the subject of public controversy for its costs to American taxpayers. In 1996, the General Accounting Office disclosed that the USAF's B-2 bombers "will be, by far, the most costly bombers to operate on a per aircraft basis", costing over three times as much as the B-1B (US$9.6 million annually) and over four times as much as the B-52H ($US6.8 million annually). In September 1997, each hour of B-2 flight necessitated 119 hours of maintenance in turn. Comparable maintenance needs for the B-52 and the B-1B are 53 and 60 hours respectively for each hour of flight. A key reason for this cost is the provision of air-conditioned hangars large enough for the bomber's 172 ft (52.4 m) wingspan, which are needed to maintain the aircraft's stealthy properties, especially its "low-observable" stealthy skins. Maintenance costs are about $3.4 million a month for each aircraft.
The total "military construction" cost related to the program was projected to be US$553.6 million in 1997 dollars. The cost to procure each B-2 was US$737 million in 1997 dollars, based only on a fleet cost of US$15.48 billion. The procurement cost per aircraft as detailed in General Accounting Office
(GAO) reports, which include spare parts and software support, was $929 million per aircraft in 1997 dollars.
The total program cost projected through 2004 was US$44.75 billion in 1997 dollars. This includes development, procurement, facilities, construction, and spare parts. The total program cost averaged US$2.13 billion per aircraft.
budget, while at the same time staving off a motion to kill the bomber. Opposition in committee and in Congress was mostly broad and bipartisan, with Congressmen Ron Dellums
(D-CA), John Kasich
(R-OH), and John G. Rowland
(R-CT) authorizing the motion to kill the bomber and others in the Senate such as Jim Exon (D-NE) and John McCain
(R-AZ) also opposing the project.
The growing cost of the B-2 program, and evidence of flaws in the aircraft's ability to elude detection by radar, were among factors that drove opposition. At the peak production period specified in 1989, the schedule called for spending US$7 billion to $8 billion per year in 1989 dollars, something Committee Chair Les Aspin
(D-WI) said "won't fly financially."
In 1990, the Department of Defense accused Northrop of using faulty components in the flight control system. Efforts have also been made to reduce the probability of bird ingestion, which could damage engine fan blades.
In time, a number of prominent members of Congress began to oppose the program's expansion, including former Democratic presidential nominee John Kerry
, who cast votes against the B-2 in 1989, 1991 and 1992 while a US Senator representing Massachusetts
. By 1992, Republican President George H.W. Bush called for the cancellation of the B-2 and promised to cut military spending by 30% in the wake of the collapse of the Soviet Union
.
In May 1995, on the basis of its 1995 Heavy Bomber Force Study, the DOD determined that additional B-2 procurements would exacerbate efforts to develop and implement long term recapitalization plans for the U.S. Air Force bomber force.
In October 1995, former Chief of Staff of the United States Air Force
, General Mike Ryan
, and Former Chairman of the Joint Chiefs of Staff, General John Shalikashvili, strongly recommended against Congressional action to fund the purchase of any additional B-2s, arguing that to do so would require unacceptable cuts in existing conventional and nuclear-capable aircraft to pay for the new bombers, and because the military had much higher priorities on which to spend its limited procurement dollars.
Some B-2 advocates argued that procuring twenty additional aircraft would save money because B-2s would be able to deeply penetrate anti-aircraft defenses and use low-cost, short-range attack weapons rather than expensive standoff weapons. However, in 1995, the Congressional Budget Office
(CBO), and its Director of National Security Analysis, found that additional B-2s would reduce the cost of weapons expended by the bomber force by less than US$2 billion in 1995 dollars during the first two weeks of a conflict, which is when the Air Force envisions bombers would make their greatest contribution. This is a small fraction of the US$26.8 billion (in 1995 dollars) life cycle cost that the CBO projected an additional 20 B-2s would cost.
In 1997, as Ranking Member
of the House Armed Services Committee and National Security Committee, Congressman Ron Dellums
(D-CA), a long-time opponent of the bomber, cited five independent studies and offered an amendment to that year's defense authorization bill to cap production of the bombers to the existing 21 aircraft. The amendment was narrowly defeated. Nonetheless, Congress did not approve funding for the purchase of any additional B-2 bombers.
has developed a new material to be used on the part of the wing trailing edge that is subject to engine exhaust to replace the current material that degrades. In 2008, the US Congress funded upgrades to the B-2's weapon control systems for hitting moving targets.
In July 2008, the B-2's computing architecture was redesigned with a new integrated processing unit (IPU) that communicates via a fiber optic network and a smaller, faster single-board processor that runs a new version of the operational flight program (OFP) software converted from JOVIAL
to C
by automated tools.
On 29 December 2008, Air Force officials awarded a production contract to Northrop Grumman to modernize the B-2 fleet's radars. The contract provides advanced radar components, with the aim of sustained operational viability of the B-2 fleet into the future. The contract has a target value of some US$468 million. The award follows successful flight testing with the upgraded equipment. A modification to the radar was needed since the US Department of Commerce
required the B-2 to use a different radar frequency. It was reported on 22 July 2009 that the B-2 had passed the second of the two USAF audit milestones associated with this upgraded AESA radar capability.
On 28 April 2009, an Air Force/contractor team verified that the 30000 lb (13,607.8 kg) Massive Ordnance Penetrator
(MOP) would fit in the B-2's bomb bay.
has posited when the B-2 is no longer able to penetrate enemy defenses, the Lockheed Martin F-35 Lightning II may take on its strike/interdiction role. The F-35 also carries the B61 nuclear bomb
as a tactical bomber and is not covered by strategic arms limitation treaties such as New START
.
The B-2's low-observable, or "stealth
", characteristics give it the ability to penetrate an enemy's most sophisticated anti-aircraft defenses to attack its most heavily defended targets. The bomber's stealth comes from a combination of reduced acoustic, infrared, visual and radar signatures, making it difficult for opposition defenses to detect, track and engage the aircraft. Many specific aspects of the low-observability process remain classified. The B-2's composite materials, special coatings and flying wing
design, which reduces the number of leading edges, contribute to its stealth characteristics. The Spirit has a radar signature of about 0.1 m2. Each B-2 requires a climate-controlled hangar large enough for its 172 feet (52.4 m) wingspan to protect the operational integrity of its sophisticated radar absorbent material and coatings. The engines are buried within the wing to conceal the engines' fans and hide their exhaust.
The blending of low-observable technologies with high aerodynamic efficiency and large payload gives the B-2 significant advantages over previous bombers. The U.S. Air Force reports its range as approximately 6000 nmi (6,904.7 mi; 11,112 km). Also, its low-observation ability provides the B-2 greater freedom of action at high altitudes, thus increasing its range and providing a better field of view for the aircraft's sensors. It combines GPS Aided Targeting System (GATS) with GPS
-aided bombs such as Joint Direct Attack Munition
(JDAM). This uses its passive electronically scanned array
APQ-181 radar
to correct GPS errors of targets and gain much better than laser-guided weapon accuracy when "unguided" gravity bombs are equipped with a GPS-aided "smart" guidance tail kit. It can bomb 16 targets in a single pass when equipped with 1,000 or 2,000-pound (450 kg or 900 kg) bombs, or as many as 80 when carrying 500 lb (226.8 kg) bombs.
The B-2 has a crew of two: a pilot in the left seat, and mission commander in the right. The B-2 has provisions for a third crew member if needed. For comparison, the B-1B has a crew of four and the B-52 has a crew of five. B-2 crews have been used to pioneer sleep cycle research to improve crew performance on long missions. The B-2 is highly automated, and, unlike two-seat fighters, one crew member can sleep, use a toilet or prepare a hot meal while the other monitors the aircraft.
As with the Boeing B-52 Stratofortress and Rockwell B-1 Lancer, the B-2 provides the versatility inherent in manned bombers. Like other bombers, its assigned targets can be canceled or changed while in flight, the particular weapon assigned to a target can be changed, and the timing of attack, or the route to the target can be changed while in flight.
The prime contractor, responsible for overall system design, integration and support, is Northrop Grumman
. Boeing
, Raytheon
(formerly Hughes Aircraft
), G.E. and Vought Aircraft Industries, are subcontractors.
The original B-2 design had tanks for a contrail
-inhibiting chemical, but this was replaced in the final design with a contrail sensor from Ophir that alerts the pilot when he should change altitude. Mission planning also considers altitudes where the probability of contrail formation is minimized.
, Missouri
, where the fleet is based, on 17 December 1993. The B-2 reached initial operational capability (IOC) on 1 January 1997. Depot maintenance for the B-2 is accomplished by U.S. Air Force contractor support and managed at Oklahoma City Air Logistics Center
at Tinker Air Force Base
. Originally designed to deliver nuclear weapons, modern usage has shifted towards a flexible role with conventional and nuclear capability.
The B-2 has seen service in four campaigns. Its combat debut was during the Kosovo War
in 1999. It was responsible for destroying 33% of selected Serbian bombing targets
in the first eight weeks of U.S. involvement in the War. During this war, B-2s flew non-stop to Kosovo from their home base in Missouri and back. The B-2 was the first aircraft to deploy GPS satellite guided JDAM "smart bombs"
in combat use in Kosovo.
The B-2 has been used to drop bombs on Afghanistan
in support of the Operation Enduring Freedom
. With the support of aerial refueling, the B-2 flew one of its longest missions to date from Whiteman Air Force Base, Missouri to Afghanistan and back.
The B-2's combat use preceded a U.S. Air Force declaration of "full operational capability" in December 2003. The Pentagon's Operational Test and Evaluation 2003 Annual Report noted that the B-2's serviceability for Fiscal Year 2003 was still inadequate, mainly due to the maintainability of the B-2's low observable coatings. The evaluation also noted that the Defensive Avionics suite also had shortcomings with "pop-up threats".
During the Iraq War (Operation Iraqi Freedom), B-2s operated from Diego Garcia
and an undisclosed "forward operating location". Other sortie
s in Iraq have launched from Whiteman AFB. This resulted in missions lasting over 30 hours and one mission of over 50 hours. "Forward operating locations" have been previously designated as Andersen Air Force Base
in Guam
and RAF Fairford
in the UK, where new climate controlled hangars have been constructed. B-2s have conducted 27 sorties from Whiteman AFB and 22 sorties from a forward operating location, releasing more than 1.5 million pounds of munitions, including 583 JDAM "smart bombs" in 2003.
All B-2s, nuclear-capable B-52s, and nuclear intercontinental ballistic missiles have shifted to the nuclear-focused Air Force Global Strike Command set up in September 2009.
In March 2011, B-2s were the first US aircraft into action in Operation Odyssey Dawn
, the UN mandated enforcement of the Libyan no-fly zone. Three B-2s dropped 40 bombs on a Libyan airfield in support of the UN no-fly zone.
B-2s are operated exclusively by the United States Air Force
active units.
in Guam
. B-2 89-0127 had been operated by the 393rd Bomb Squadron, 509th Bomb Wing
, Whiteman Air Force Base
, Missouri
, and had logged 5,176 flight hours. It was the first crash of a B-2. The two person crew ejected safely from the aircraft and survived the crash. The aircraft was completely destroyed, a hull loss
valued at US$1.4 billion. After the accident, the Air Force took the B-2 fleet off operational status until clearing the fleet for flight status 53 days later on 15 April 2008. The cause of the crash was later determined to be moisture in the aircraft's Port Transducer Units during air data calibration, which distorted the information being sent to the bomber's air data system. As a result, the flight control computers calculated an inaccurate airspeed, and a negative angle of attack, causing the aircraft to pitch upward 30 degrees during takeoff.
Because of its high cost, strategic bombing
role, and the still-classified aspects of its low observable coatings, no production B-2 has been placed on permanent display. However, B-2s have made periodic appearances on ground display at various air show
s.
Later avionics and equipment improvements allow B-2A to carry JSOW, GBU-28
, and GBU-57A/Bs as well. The Spirit is also designated as a delivery aircraft for the AGM-158 JASSM
when the missile enters service.
Sources: FAS.org, B-2 Spirit (Pace)
Heavy bomber
A heavy bomber is a bomber aircraft of the largest size and load carrying capacity, and usually the longest range.In New START, the term "heavy bomber" is used for two types of bombers:*one with a range greater than 8,000 kilometers...
with low observable stealth
Stealth aircraft
Stealth aircraft are aircraft that use stealth technology to avoid detection by employing a combination of features to interfere with radar as well as reduce visibility in the infrared, visual, audio, and radio frequency spectrum. Development of stealth technology likely began in Germany during...
technology designed to penetrate
Penetration (warfare)
Penetration is a term in warfare referring to the breaching of, and moving past, a defensive military line. The term is associated with both ground and aerial combat.-Ground combat:...
dense anti-aircraft defenses
Anti-aircraft warfare
NATO defines air defence as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be to protect naval, ground and air forces...
and deploy both conventional and nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
s. The bomber has a crew of two and can drop up to eighty 500 lb (226.8 kg)-class JDAM
Joint Direct Attack Munition
The Joint Direct Attack Munition is a guidance kit that converts unguided bombs, or "dumb bombs" into all-weather "smart" munitions. JDAM-equipped bombs are guided by an integrated inertial guidance system coupled to a Global Positioning System receiver, giving them a published range of up to...
GPS-guided bombs, or sixteen 2400 lb (1,088.6 kg) B83 nuclear bomb
B83 nuclear bomb
The B83 nuclear weapon is a variable yield gravity bomb developed by the United States in the late 1970s, entering service in 1983. With a maximum yield of 1.2 megatons, it is currently the most powerful atomic weapon in the US arsenal...
s. The B-2 is the only aircraft that can carry large air to surface standoff weapons in a stealth configuration.
Development originally started under the "Advanced Technology Bomber" (ATB) project during the Carter administration
Presidency of Jimmy Carter
Jimmy Carter served as the thirty-ninth President of the United States from 1977 to 1981. His administration sought to make the government "competent and compassionate" but, in the midst of an economic crisis produced by rising energy prices and stagflation, met with difficulty in achieving its...
, and its performance was one of the reasons for his cancellation of the B-1 Lancer
B-1 Lancer
The Rockwell B-1 LancerThe name "Lancer" is only applied to the B-1B version, after the program was revived. is a four-engine variable-sweep wing strategic bomber used by the United States Air Force...
. 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
Northrop Grumman
Northrop Grumman Corporation is an American global aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. The company was the fourth-largest defense contractor in the world as of 2010, and the largest builder of naval vessels. Northrop Grumman employs over...
with assistance from Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
, the cost of each aircraft averaged US$737 million (in 1997 dollars). Total procurement
Procurement
Procurement is the acquisition of goods or services. It is favourable that the goods/services are appropriate and that they are procured at the best possible cost to meet the needs of the purchaser in terms of quality and quantity, time, and location...
costs averaged $929 million per aircraft, which includes spare parts, equipment, retrofitting, and software support. The total program cost, which includes development, engineering and testing, averaged $2.1 billion per aircraft in 1997.
Because of its considerable capital and operational costs, the project
Megaproject
A megaproject is an extremely large-scale investment project. Megaprojects are typically defined as costing more than US$1 billion and attracting a lot of public attention because of substantial impacts on communities, environment, and budgets. Megaprojects can also be defined as "initiatives that...
was controversial in the U.S. Congress
United States Congress
The United States Congress is the bicameral legislature of the federal government of the United States, consisting of the Senate and the House of Representatives. The Congress meets in the United States Capitol in Washington, D.C....
and among the Joint Chiefs of Staff
Joint Chiefs of Staff
The Joint Chiefs of Staff is a body of senior uniformed leaders in the United States Department of Defense who advise the Secretary of Defense, the Homeland Security Council, the National Security Council and the President on military matters...
. The winding-down of the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
in the later 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 early 1990s, the Congress slashed initial plans to purchase 132 bombers to 21. In 2008 one bomber crashed just after takeoff and was destroyed as the crew ejected safely. A total of 20 B-2s remain in service with the United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
.
Though originally designed primarily as a nuclear bomber, the B-2 was first used in combat to drop conventional bomb
Bomb
A bomb is any of a range of explosive weapons that only rely on the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy...
s on Serbia
Serbia
Serbia , officially the Republic of Serbia , is a landlocked country located at the crossroads of Central and Southeast Europe, covering the southern part of the Carpathian basin and the central part of the Balkans...
during the Kosovo War
Kosovo War
The term Kosovo War or Kosovo conflict was two sequential, and at times parallel, armed conflicts in Kosovo province, then part of FR Yugoslav Republic of Serbia; from early 1998 to 1999, there was an armed conflict initiated by the ethnic Albanian "Kosovo Liberation Army" , who sought independence...
in 1999, and saw continued use during the wars in Iraq and Afghanistan. B-2s were also used during the 2011 Libyan uprising.
Origins
In the mid-1970s the search for a new US strategic bomberStrategic bomber
A strategic bomber is a heavy bomber aircraft designed to drop large amounts of ordnance onto a distant target for the purposes of debilitating an enemy's capacity to wage war. Unlike tactical bombers, which are used in the battle zone to attack troops and military equipment, strategic bombers are...
to replace the Boeing B-52 Stratofortress was underway, with nothing to show for it. First the B-70 and then the B-1A were canceled after only small numbers were built. The B-70 was intended to fly above and beyond defensive interceptor aircraft
Interceptor aircraft
An interceptor aircraft is a type of fighter aircraft designed specifically to prevent missions of enemy aircraft, particularly bombers and reconnaissance aircraft. Interceptors generally rely on high speed and powerful armament in order to complete their mission as quickly as possible and set up...
, only to find these same attributes made it especially vulnerable to surface-to-air missile
Surface-to-air missile
A surface-to-air missile or ground-to-air missile is a missile designed to be launched from the ground to destroy aircraft or other missiles...
s (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
Look-down/shoot-down
Look-down/shoot-down is a capability a radar system is said to possess if it is able to detect, track and put a weapon onto an air target moving below the horizon as seen by the radar...
capabilities that could attack them from above.
However, technology continued to progress throughout. By the mid-1970s it was becoming clear that there was an entirely different way to avoid missiles and intercepts. Known today as "stealth
Stealth aircraft
Stealth aircraft are aircraft that use stealth technology to avoid detection by employing a combination of features to interfere with radar as well as reduce visibility in the infrared, visual, audio, and radio frequency spectrum. Development of stealth technology likely began in Germany during...
", the idea was to build an aircraft with an airframe that deflected or absorbed radar signals so that too little was reflected back to the radar unit. An aircraft that was stealthy enough would be able to fly wherever it pleased, and could be attacked only by weapons and systems that did not rely on radar. Although such possibilities exist, notably human observers, ranges were so short that most aircraft could fly right by the defence with impunity, especially at night.
In 1974 DARPA requested information from US aviation firms about the largest radar cross section
Radar cross section
Radar cross section is a measure of how detectable an object is with a radar. A larger RCS indicates that an object is more easily detected.An object reflects a limited amount of radar energy...
of an aircraft where it would remain effectively invisible to radars. Initially, Northrop
Northrop
Northrop Corporation was a major United States aircraft manufacturer which merged with Grumman in 1994 to form Northrop Grumman.Northrop may also refer to:-Places:In the United States:* Northrop, Minnesota, a town...
and McDonnell Douglas
McDonnell Douglas
McDonnell Douglas was a major American aerospace manufacturer and defense contractor, producing a number of famous commercial and military aircraft. It formed from a merger of McDonnell Aircraft and Douglas Aircraft in 1967. McDonnell Douglas was based at Lambert-St. Louis International Airport...
were selected for further work. Lockheed had experience in this field due to their work on the Lockheed 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 finish in radar absorbing paint. A key improvement was the introduction of computer models that could be used to predict the reflections from flat surfaces and could be used to design a "faceted" aircraft. Work on the first such designs had started in 1975 with "the hopeless diamond", a model built at Lockheed to test the concepts. Improvements quickly followed that allowed designs with more traditional layouts and construction techniques.
These plans were well advanced by the summer of 1975, when DARPA started the Experimental Survivability Testbed (XST) project. Northrop and Lockheed won the first round of testing, and Lockheed was the sole winner of the second round in April 1976. This led to the Have Blue program.
ATB program
By 1976 these programs had advanced to the point where the concept of a long-range strategic stealth bomber appeared to be a safe bet. Whereas the B-1 relied on flying around known defense sites and could only change its mission within a limited selection of pre-selected routes, a stealth bomber would be able to overfly the Soviet Union with impunity, allowing it to loiter and hunt for targets instead of simply running in and out as fast as possible. In a nuclear exchange, this would allow it to wait out the initial attacks and find targets that escaped destruction, eliminating the "overkill" that was built into existing war planning. Better yet, as the need for high speed was reduced or eliminated, and all of the extremely expensive electronic warfareElectronic warfare
Electronic warfare refers to any action involving the use of the electromagnetic spectrum or directed energy to control the spectrum, attack an enemy, or impede enemy assaults via the spectrum. The purpose of electronic warfare is to deny the opponent the advantage of, and ensure friendly...
equipment removed, the aircraft would be much simpler and less expensive.
Carter was aware of these developments during 1977, and it appears to have been one of the major reasons the B-1 was canceled. 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
Ronald Reagan
Ronald Wilson Reagan was the 40th President of the United States , the 33rd Governor of California and, prior to that, a radio, film and television actor....
repeatedly complained that Carter was weak on defence, 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
United States Department of Defense
The United States Department of Defense is the U.S...
(DoD) was working to develop stealth aircraft, including a bomber.
The Advanced Technology Bomber (ATB) began in 1979. Full development of the black project
Black project
In the United States and United Kingdom, a black project is in the vernacular a classified military/defense project, unacknowledged publicly by the government, military personnel, and defense contractors. Examples of U.S...
followed. The black program was funded under the code name "Aurora". After the evaluations of the companies' proposals, the ATB competition was reduced to the Northrop
Northrop Corporation
Northrop Corporation was a leading United States aircraft manufacturer from its formation in 1939 until its merger with Grumman to form Northrop Grumman in 1994. The company is known for its development of the flying wing design, although only a few of these have entered service.-History:Jack...
/Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
and Lockheed
Lockheed Corporation
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...
/Rockwell
Rockwell International
Rockwell International was a major American manufacturing conglomerate in the latter half of the 20th century, involved in aircraft, the space industry, both defense-oriented and commercial electronics, automotive and truck components, printing presses, valves and meters, and industrial automation....
teams with each receiving a study contract for further work. Both teams used flying wing designs. Northrop had previous experience from the development of the YB-35
Northrop YB-35
The Northrop XB-35 and YB-35 were experimental heavy bomber aircraft developed for the United States Army Air Forces during and shortly after World War II by the Northrop Corporation. It used the radical and potentially very efficient flying wing design, in which the tail section and fuselage are...
and YB-49
Northrop YB-49
The Northrop YB-49 was a prototype jet-powered heavy bomber aircraft developed by Northrop shortly after World War II. Intended for service with the U.S. Air Force, the YB-49 featured a flying wing design...
flying wing aircraft. The Northrop design was larger while the Lockheed design included a small tail.
The Northrop/Boeing team's ATB design was selected over the Lockheed/Rockwell design on 20 October 1981. 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. An estimated US$23 billion was secretly spent for research and development
Research and development
The phrase research and development , according to the Organization for Economic Co-operation and Development, refers to "creative work undertaken on a systematic basis in order to increase the stock of knowledge, including knowledge of man, culture and society, and the use of this stock of...
on the B-2 by 1989.
The B-2 was first publicly displayed on 22 November 1988, at Air Force Plant 42
Plant 42
Air Force Plant 42 is a federally owned military aerospace facility under the control of the Air Force Material Command in Palmdale, California...
, Palmdale
Palmdale, California
Palmdale is a city located in the center of northern Los Angeles County, California, United States.Palmdale was the first community within the Antelope Valley to incorporate as a city on August 24, 1962; 47 years later, voters approved creating a charter city in November, 2009. Palmdale is...
, California, where it was assembled. This initial viewing was heavily guarded and guests were not allowed to see the rear of the B-2. However, Aviation Week
Aviation Week & Space Technology
Aviation Week & Space Technology, often abbreviated Aviation Week or AW&ST, is a weekly magazine owned and published by McGraw-Hill...
editors found that there was no ban on overflying the airfield apron/presentation area and, to the chagrin of the USAF, took pictures from above of the aircraft's then-secret planform
Planform
In aviation, a planform is the shape and layout of a fixed-wing aircraft's fuselage and wing. Of all the myriad planforms used, they can typically be grouped into those used for low-speed flight, found on general aviation aircraft, and those used for high-speed flight, found on many military...
and suppressed engine exhausts. The B-2's first public flight was on 17 July 1989 from Palmdale. At the program's peak, approximately 13,000 people were employed at a dedicated plant in Pico Rivera, California
Pico Rivera, California
Pico Rivera is a city located in southeastern Los Angeles County, California, United States. The city is situated approximately 11 miles southeast of downtown Los Angeles, on the eastern edge of the Los Angeles basin, and on the southern edge of the area known as the San Gabriel Valley...
for the aircraft's engineering and portions of its manufacturing.
Espionage
In 1984, a NorthropNorthrop Corporation
Northrop Corporation was a leading United States aircraft manufacturer from its formation in 1939 until its merger with Grumman to form Northrop Grumman in 1994. The company is known for its development of the flying wing design, although only a few of these have entered service.-History:Jack...
employee, Thomas Cavanaugh
Thomas Patrick Cavanaugh
Thomas Patrick Cavanaugh is an aerospace engineer who was sentenced in 1985 after being convicted of trying to sell stealth bomber secrets to the Soviet Union....
, was arrested for attempting to sell classified information
Classified information
Classified information is sensitive information to which access is restricted by law or regulation to particular groups of persons. A formal security clearance is required to handle classified documents or access classified data. The clearance process requires a satisfactory background investigation...
to the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
, which apparently was smuggled out of the Pico Rivera, California factory. Cavanaugh was eventually sentenced to life in prison and released on parole in 2001.
Noshir Gowadia
Noshir Gowadia
Noshir Sheriarji Gowadia, born in Bombay, India in 1944 is an Indian American design engineer of Parsi descent. One of the creators of the B-2 Spirit stealth bomber during a career at Northrop, he was arrested in 2005 on espionage-related federal charges...
, a design engineer who worked on the B-2's propulsion system, was arrested in October 2005 for selling B-2 related classified information to foreign countries. On 9 August 2010, Gowadia was convicted in the United States District Court
United States district court
The United States district courts are the general trial courts of the United States federal court system. Both civil and criminal cases are filed in the district court, which is a court of law, equity, and admiralty. There is a United States bankruptcy court associated with each United States...
for the District of Hawaii on 14 of 17 charges against him. On 24 January 2011, Gowadia was sentenced to 32 years in prison.
Program costs and procurement
A procurement of 132 aircraft was planned in the mid-1980s, but was later reduced to 75. By the early 1990s, the Soviet UnionSoviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
had disintegrated, which effectively eliminated the Spirit's primary Cold War mission. Under budgetary pressures and congressional opposition, in his 1992 State of the Union Address
State of the Union Address
The State of the Union is an annual address presented by the President of the United States to the United States Congress. The address not only reports on the condition of the nation but also allows the president to outline his legislative agenda and his national priorities.The practice arises...
, President George H.W. Bush announced B-2 production would be limited to 20 aircraft. In 1996, however, the Clinton administration, though originally committed to ending production of the bombers at 20 aircraft, authorized the conversion of a 21st bomber, a prototype
Prototype
A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
test model, to Block 30 fully operational status at a cost of nearly $500 million.
In 1995, Northrop made a proposal to the USAF to build 20 additional aircraft with a flyaway cost
Flyaway cost
Flyaway cost is one measure of the cost of an aircraft. It values the aircraft at its marginal cost, including only the cost of production and production tools immediately accruing to the building of a single unit...
of $566 million each.
The program was the subject of public controversy for its costs to American taxpayers. In 1996, the General Accounting Office disclosed that the USAF's B-2 bombers "will be, by far, the most costly bombers to operate on a per aircraft basis", costing over three times as much as the B-1B (US$9.6 million annually) and over four times as much as the B-52H ($US6.8 million annually). In September 1997, each hour of B-2 flight necessitated 119 hours of maintenance in turn. Comparable maintenance needs for the B-52 and the B-1B are 53 and 60 hours respectively for each hour of flight. A key reason for this cost is the provision of air-conditioned hangars large enough for the bomber's 172 ft (52.4 m) wingspan, which are needed to maintain the aircraft's stealthy properties, especially its "low-observable" stealthy skins. Maintenance costs are about $3.4 million a month for each aircraft.
Government Accountability Office
The Government Accountability Office is the audit, evaluation, and investigative arm of the United States Congress. It is located in the legislative branch of the United States government.-History:...
(GAO) reports, which include spare parts and software support, was $929 million per aircraft in 1997 dollars.
The total program cost projected through 2004 was US$44.75 billion in 1997 dollars. This includes development, procurement, facilities, construction, and spare parts. The total program cost averaged US$2.13 billion per aircraft.
Opposition
In its consideration of the fiscal year 1990 defense budget, the House Armed Services Committee trimmed $800 million from the B-2 research and developmentResearch and development
The phrase research and development , according to the Organization for Economic Co-operation and Development, refers to "creative work undertaken on a systematic basis in order to increase the stock of knowledge, including knowledge of man, culture and society, and the use of this stock of...
budget, while at the same time staving off a motion to kill the bomber. Opposition in committee and in Congress was mostly broad and bipartisan, with Congressmen Ron Dellums
Ron Dellums
Ronald Vernie "Ron" Dellums served as Oakland's forty-fifth mayor. From 1971 to 1998, he was elected to thirteen terms as a Member of the U.S...
(D-CA), John Kasich
John Kasich
John Richard Kasich is the 69th and current Governor of Ohio. A member of the Republican Party, he previously served as a member of the United States House of Representatives, representing from 1983 to 2001...
(R-OH), and John G. Rowland
John G. Rowland
John Grosvenor Rowland was the 86th Governor of Connecticut from 1995 to 2004; he is a member of the Republican Party. He is married to Patty Rowland, his second wife, and the couple have five children between them...
(R-CT) authorizing the motion to kill the bomber and others in the Senate such as Jim Exon (D-NE) and John McCain
John McCain
John Sidney McCain III is the senior United States Senator from Arizona. He was the Republican nominee for president in the 2008 United States election....
(R-AZ) also opposing the project.
The growing cost of the B-2 program, and evidence of flaws in the aircraft's ability to elude detection by radar, were among factors that drove opposition. At the peak production period specified in 1989, the schedule called for spending US$7 billion to $8 billion per year in 1989 dollars, something Committee Chair Les Aspin
Les Aspin
Leslie "Les" Aspin, Jr. was a United States Representative from 1971 to 1993, and the United States Secretary of Defense under President Bill Clinton from January 21, 1993 to February 3, 1994.-Early life:...
(D-WI) said "won't fly financially."
In 1990, the Department of Defense accused Northrop of using faulty components in the flight control system. Efforts have also been made to reduce the probability of bird ingestion, which could damage engine fan blades.
In time, a number of prominent members of Congress began to oppose the program's expansion, including former Democratic presidential nominee John Kerry
John Kerry
John Forbes Kerry is the senior United States Senator from Massachusetts, the 10th most senior U.S. Senator and chairman of the Senate Foreign Relations Committee. He was the presidential nominee of the Democratic Party in the 2004 presidential election, but lost to former President George W...
, who cast votes against the B-2 in 1989, 1991 and 1992 while a US Senator representing Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
. By 1992, Republican President George H.W. Bush called for the cancellation of the B-2 and promised to cut military spending by 30% in the wake of the collapse of the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
.
In May 1995, on the basis of its 1995 Heavy Bomber Force Study, the DOD determined that additional B-2 procurements would exacerbate efforts to develop and implement long term recapitalization plans for the U.S. Air Force bomber force.
In October 1995, former Chief of Staff of the United States Air Force
Chief of Staff of the United States Air Force
The Chief of Staff of the Air Force is a statutory office held by a four-star general in the United States Air Force, and is the most senior uniformed officer assigned to serve in the Department of the Air Force, and as such is the principal military advisor and a deputy to the Secretary of the...
, General Mike Ryan
Michael E. Ryan
Michael E. Ryan is a retired United States Air Force general and was the 16th Chief of Staff of the United States Air Force. He served as the senior uniformed Air Force officer responsible for the organization, training and equipage of 700,000 active-duty, Guard, Reserve and civilian forces...
, and Former Chairman of the Joint Chiefs of Staff, General John Shalikashvili, strongly recommended against Congressional action to fund the purchase of any additional B-2s, arguing that to do so would require unacceptable cuts in existing conventional and nuclear-capable aircraft to pay for the new bombers, and because the military had much higher priorities on which to spend its limited procurement dollars.
Some B-2 advocates argued that procuring twenty additional aircraft would save money because B-2s would be able to deeply penetrate anti-aircraft defenses and use low-cost, short-range attack weapons rather than expensive standoff weapons. However, in 1995, the Congressional Budget Office
Congressional Budget Office
The Congressional Budget Office is a federal agency within the legislative branch of the United States government that provides economic data to Congress....
(CBO), and its Director of National Security Analysis, found that additional B-2s would reduce the cost of weapons expended by the bomber force by less than US$2 billion in 1995 dollars during the first two weeks of a conflict, which is when the Air Force envisions bombers would make their greatest contribution. This is a small fraction of the US$26.8 billion (in 1995 dollars) life cycle cost that the CBO projected an additional 20 B-2s would cost.
In 1997, as Ranking Member
Ranking member
In United States politics, a ranking member is the second-most senior member of a congressional or state legislative committee from the majority party. Another usage refers to the most senior member of a congressional or state legislative committee from the minority party. This second usage, often...
of the House Armed Services Committee and National Security Committee, Congressman Ron Dellums
Ron Dellums
Ronald Vernie "Ron" Dellums served as Oakland's forty-fifth mayor. From 1971 to 1998, he was elected to thirteen terms as a Member of the U.S...
(D-CA), a long-time opponent of the bomber, cited five independent studies and offered an amendment to that year's defense authorization bill to cap production of the bombers to the existing 21 aircraft. The amendment was narrowly defeated. Nonetheless, Congress did not approve funding for the purchase of any additional B-2 bombers.
Upgrades
A number of upgrade packages were applied to the B-2 during the 21st century. In 2004, Northrop Grumman tested a new alternate high-frequency material (AHFM) for use as a RAM coating for the B-2. The Air Force Research LaboratoryAir Force Research Laboratory
The Air Force Research Laboratory is a scientific research organization operated by the United States Air Force Materiel Command dedicated to leading the discovery, development, and integration of affordable aerospace warfighting technologies; planning and executing the Air Force science and...
has developed a new material to be used on the part of the wing trailing edge that is subject to engine exhaust to replace the current material that degrades. In 2008, the US Congress funded upgrades to the B-2's weapon control systems for hitting moving targets.
In July 2008, the B-2's computing architecture was redesigned with a new integrated processing unit (IPU) that communicates via a fiber optic network and a smaller, faster single-board processor that runs a new version of the operational flight program (OFP) software converted from JOVIAL
JOVIAL
JOVIAL is a high-order computer programming language similar to ALGOL, but specialized for the development of embedded systems .JOVIAL is an acronym for "Jules Own Version of the International...
to C
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
by automated tools.
On 29 December 2008, Air Force officials awarded a production contract to Northrop Grumman to modernize the B-2 fleet's radars. The contract provides advanced radar components, with the aim of sustained operational viability of the B-2 fleet into the future. The contract has a target value of some US$468 million. The award follows successful flight testing with the upgraded equipment. A modification to the radar was needed since the US Department of Commerce
United States Department of Commerce
The United States Department of Commerce is the Cabinet department of the United States government concerned with promoting economic growth. It was originally created as the United States Department of Commerce and Labor on February 14, 1903...
required the B-2 to use a different radar frequency. It was reported on 22 July 2009 that the B-2 had passed the second of the two USAF audit milestones associated with this upgraded AESA radar capability.
On 28 April 2009, an Air Force/contractor team verified that the 30000 lb (13,607.8 kg) Massive Ordnance Penetrator
Massive Ordnance Penetrator
The Massive Ordnance Penetrator GBU-57A/B is a project by the U.S. Air Force to develop a massive, precision-guided, "bunker buster" bomb...
(MOP) would fit in the B-2's bomb bay.
Future developments
The Pentagon is currently (as of 2011) evaluating a radically different unmanned stealth bomber, characterized as a "mini-B2", to come into operational service by 2020. During a transition period, US political expert Rebecca GrantRebecca Grant (political expert)
Rebecca L. Grant is the Director of the General Billy Mitchell Institute for Airpower Studies at the Air Force Association and a contributing editor for their Air Force Magazine.She is also a senior fellow at the Lexington Institute. She earned her Ph.D...
has posited when the B-2 is no longer able to penetrate enemy defenses, the Lockheed Martin F-35 Lightning II may take on its strike/interdiction role. The F-35 also carries the B61 nuclear bomb
B61 nuclear bomb
The B61 nuclear bomb is the primary thermonuclear weapon in the U.S. Enduring Stockpile following the end of the Cold War. It is an intermediate yield strategic and tactical nuclear weapon featuring a two-stage radiation implosion design....
as a tactical bomber and is not covered by strategic arms limitation treaties such as New START
New START
New START is a nuclear arms reduction treaty between the United States of America and the Russian Federation with the formal name of Measures for the Further Reduction and Limitation of Strategic Offensive Arms...
.
Design
Stealth aircraft
Stealth aircraft are aircraft that use stealth technology to avoid detection by employing a combination of features to interfere with radar as well as reduce visibility in the infrared, visual, audio, and radio frequency spectrum. Development of stealth technology likely began in Germany during...
", characteristics give it the ability to penetrate an enemy's most sophisticated anti-aircraft defenses to attack its most heavily defended targets. The bomber's stealth comes from a combination of reduced acoustic, infrared, visual and radar signatures, making it difficult for opposition defenses to detect, track and engage the aircraft. Many specific aspects of the low-observability process remain classified. The B-2's composite materials, special coatings and flying wing
Flying wing
A flying wing is a tailless fixed-wing aircraft which has no definite fuselage, with most of the crew, payload and equipment being housed inside the main wing structure....
design, which reduces the number of leading edges, contribute to its stealth characteristics. The Spirit has a radar signature of about 0.1 m2. Each B-2 requires a climate-controlled hangar large enough for its 172 feet (52.4 m) wingspan to protect the operational integrity of its sophisticated radar absorbent material and coatings. The engines are buried within the wing to conceal the engines' fans and hide their exhaust.
The blending of low-observable technologies with high aerodynamic efficiency and large payload gives the B-2 significant advantages over previous bombers. The U.S. Air Force reports its range as approximately 6000 nmi (6,904.7 mi; 11,112 km). Also, its low-observation ability provides the B-2 greater freedom of action at high altitudes, thus increasing its range and providing a better field of view for the aircraft's sensors. It combines GPS Aided Targeting System (GATS) with GPS
Global Positioning System
The Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...
-aided bombs such as Joint Direct Attack Munition
Joint Direct Attack Munition
The Joint Direct Attack Munition is a guidance kit that converts unguided bombs, or "dumb bombs" into all-weather "smart" munitions. JDAM-equipped bombs are guided by an integrated inertial guidance system coupled to a Global Positioning System receiver, giving them a published range of up to...
(JDAM). This uses its passive electronically scanned array
Passive electronically scanned array
A passive electronically scanned array , contrary to its active counterpart AESA, is a phased array which has a central radiofrequency source , sending energy into phase shift modules, which then send energy into the various emitting elements in the front of the antenna...
APQ-181 radar
APQ-181 radar
The AN/APQ-181 is an all-weather, low probability of intercept radar system designed by Hughes Aircraft for the U.S. Air Force B-2A Spirit bomber aircraft. The system was developed in the mid-1980s and entered service in 1993. The APQ-181 provides a number of precision targeting modes, and also...
to correct GPS errors of targets and gain much better than laser-guided weapon accuracy when "unguided" gravity bombs are equipped with a GPS-aided "smart" guidance tail kit. It can bomb 16 targets in a single pass when equipped with 1,000 or 2,000-pound (450 kg or 900 kg) bombs, or as many as 80 when carrying 500 lb (226.8 kg) bombs.
The B-2 has a crew of two: a pilot in the left seat, and mission commander in the right. The B-2 has provisions for a third crew member if needed. For comparison, the B-1B has a crew of four and the B-52 has a crew of five. B-2 crews have been used to pioneer sleep cycle research to improve crew performance on long missions. The B-2 is highly automated, and, unlike two-seat fighters, one crew member can sleep, use a toilet or prepare a hot meal while the other monitors the aircraft.
As with the Boeing B-52 Stratofortress and Rockwell B-1 Lancer, the B-2 provides the versatility inherent in manned bombers. Like other bombers, its assigned targets can be canceled or changed while in flight, the particular weapon assigned to a target can be changed, and the timing of attack, or the route to the target can be changed while in flight.
Northrop Grumman
Northrop Grumman Corporation is an American global aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. The company was the fourth-largest defense contractor in the world as of 2010, and the largest builder of naval vessels. Northrop Grumman employs over...
. Boeing
Boeing Integrated Defense Systems
Boeing Defense, Space & Security formerly known as Boeing Integrated Defense Systems is a unit of The Boeing Company responsible for defense and aerospace products and services. Boeing Integrated Defense Systems was formed in 2002 by combining the former "Military Aircraft and Missile Systems"...
, Raytheon
Raytheon
Raytheon Company is a major American defense contractor and industrial corporation with core manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007...
(formerly Hughes Aircraft
Hughes Aircraft
Hughes Aircraft Company was a major American aerospace and defense contractor founded in 1932 by Howard Hughes in Culver City, California as a division of Hughes Tool Company...
), G.E. and Vought Aircraft Industries, are subcontractors.
The original B-2 design had tanks for a contrail
Contrail
Contrails or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines...
-inhibiting chemical, but this was replaced in the final design with a contrail sensor from Ophir that alerts the pilot when he should change altitude. Mission planning also considers altitudes where the probability of contrail formation is minimized.
Operational history
The first operational aircraft, christened Spirit of Missouri, was delivered to Whiteman Air Force BaseWhiteman Air Force Base
Whiteman Air Force Base is a United States Air Force base located approximately south of Knob Noster, Missouri; east-southeast of Kansas City, Missouri....
, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
, where the fleet is based, on 17 December 1993. The B-2 reached initial operational capability (IOC) on 1 January 1997. Depot maintenance for the B-2 is accomplished by U.S. Air Force contractor support and managed at Oklahoma City Air Logistics Center
Oklahoma City Air Logistics Center
The Oklahoma City Air Logistics Center performs sustainment and depot maintenance on a number of US Air Force weapon systems. Specifically it supports B-1 Lancer, B-2 Spirit, B-52 Stratofortress, KC-135 Stratotanker, and E-3 Sentry systems. Additionally, the center is responsible for aircraft...
at Tinker Air Force Base
Tinker Air Force Base
Tinker Air Force Base is a major U.S. Air Force base, with tenant U.S. Navy and other Department of Defense missions, located in the southeast Oklahoma City, Oklahoma area, directly south of the suburb of Midwest City, Oklahoma.-Overview:...
. Originally designed to deliver nuclear weapons, modern usage has shifted towards a flexible role with conventional and nuclear capability.
Into combat
Kosovo War
The term Kosovo War or Kosovo conflict was two sequential, and at times parallel, armed conflicts in Kosovo province, then part of FR Yugoslav Republic of Serbia; from early 1998 to 1999, there was an armed conflict initiated by the ethnic Albanian "Kosovo Liberation Army" , who sought independence...
in 1999. It was responsible for destroying 33% of selected Serbian bombing targets
Bullseye (target)
The bullseye, or bull's-eye, is the centre of a target , and by extension the name given to any shot that hits the bullseye...
in the first eight weeks of U.S. involvement in the War. During this war, B-2s flew non-stop to Kosovo from their home base in Missouri and back. The B-2 was the first aircraft to deploy GPS satellite guided JDAM "smart bombs"
Joint Direct Attack Munition
The Joint Direct Attack Munition is a guidance kit that converts unguided bombs, or "dumb bombs" into all-weather "smart" munitions. JDAM-equipped bombs are guided by an integrated inertial guidance system coupled to a Global Positioning System receiver, giving them a published range of up to...
in combat use in Kosovo.
The B-2 has been used to drop bombs on Afghanistan
Afghanistan
Afghanistan , officially the Islamic Republic of Afghanistan, is a landlocked country located in the centre of Asia, forming South Asia, Central Asia and the Middle East. With a population of about 29 million, it has an area of , making it the 42nd most populous and 41st largest nation in the world...
in support of the Operation Enduring Freedom
War in Afghanistan (2001–present)
The War in Afghanistan began on October 7, 2001, as the armed forces of the United States of America, the United Kingdom, Australia, and the Afghan United Front launched Operation Enduring Freedom...
. With the support of aerial refueling, the B-2 flew one of its longest missions to date from Whiteman Air Force Base, Missouri to Afghanistan and back.
The B-2's combat use preceded a U.S. Air Force declaration of "full operational capability" in December 2003. The Pentagon's Operational Test and Evaluation 2003 Annual Report noted that the B-2's serviceability for Fiscal Year 2003 was still inadequate, mainly due to the maintainability of the B-2's low observable coatings. The evaluation also noted that the Defensive Avionics suite also had shortcomings with "pop-up threats".
During the Iraq War (Operation Iraqi Freedom), B-2s operated from Diego Garcia
Diego Garcia
Diego Garcia is a tropical, footprint-shaped coral atoll located south of the equator in the central Indian Ocean at 7 degrees, 26 minutes south latitude. It is part of the British Indian Ocean Territory [BIOT] and is positioned at 72°23' east longitude....
and an undisclosed "forward operating location". Other sortie
Sortie
Sortie is a term for deployment or dispatch of one military unit, be it an aircraft, ship, or troops from a strongpoint. The sortie, whether by one or more aircraft or vessels, usually has a specific mission....
s in Iraq have launched from Whiteman AFB. This resulted in missions lasting over 30 hours and one mission of over 50 hours. "Forward operating locations" have been previously designated as Andersen Air Force Base
Andersen Air Force Base
Andersen Air Force Base is a United States Air Force base located approximately northeast of Yigo in the United States territory of Guam....
in Guam
Guam
Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United...
and RAF Fairford
RAF Fairford
RAF Fairford is a Royal Air Force station in Gloucestershire, England. It is a standby airfield, not in everyday use. Its most prominent use in recent years has been as an airfield for United States Air Force B-52s during the 2003 Iraq War, Operation Allied Force in 1999, and the first Gulf War in...
in the UK, where new climate controlled hangars have been constructed. B-2s have conducted 27 sorties from Whiteman AFB and 22 sorties from a forward operating location, releasing more than 1.5 million pounds of munitions, including 583 JDAM "smart bombs" in 2003.
All B-2s, nuclear-capable B-52s, and nuclear intercontinental ballistic missiles have shifted to the nuclear-focused Air Force Global Strike Command set up in September 2009.
In March 2011, B-2s were the first US aircraft into action in Operation Odyssey Dawn
Operation Odyssey Dawn
Operation Odyssey Dawn was the U.S. code name for the US part of the international military operation in Libya to enforce United Nations Security Council Resolution 1973. during the initial period of 19–31 March 2011, which continued afterwards under NATO command as Operation Unified Protector...
, the UN mandated enforcement of the Libyan no-fly zone. Three B-2s dropped 40 bombs on a Libyan airfield in support of the UN no-fly zone.
Operators
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
active units.
- United States Air ForceUnited States Air ForceThe United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
- 509th Bomb Wing509th Bomb WingThe 509th Bomb Wing is a United States Air Force unit assigned to the Air Force Global Strike Command, Eighth Air Force. It is stationed at Whiteman Air Force Base, Missouri....
, Whiteman Air Force BaseWhiteman Air Force BaseWhiteman Air Force Base is a United States Air Force base located approximately south of Knob Noster, Missouri; east-southeast of Kansas City, Missouri....
(currently has 19 B-2s)- 13th Bomb Squadron13th Bomb SquadronThe 13th Bomb Squadron is an active United States Air Force organization assigned to the 509th Operations Group, stationed at Whiteman Air Force Base, Missouri...
- 393d Bomb Squadron393d Bomb SquadronThe 393d Bomb Squadron is part of the 509th Bomb Wing at Whiteman Air Force Base, Missouri.-History:Activated as a B-29 Superfortress squadron in early 1944; trained under Second Air Force. Training delayed as engineering flaws being worked out of the B-29...
- 394th Combat Training Squadron394th Combat Training SquadronThe 394th Combat Training Squadron is a United States Air Force unit, assigned to the 509th Operations Group. It is stationed at Whiteman AFB, Missouri. The mission of the squadron is to train B-2 Spirit Aircrews.-History:...
- 13th Bomb Squadron
- 131st Bomb Wing131st Bomb WingThe United States Air Force's 131st Bomb Wing is a B-2 unit of the Missouri Air National Guard. It is located at Whiteman AFB, in association with the 509th Bomb Wing of the active duty United States Air Force, and a small Guard base located at Lambert-St. Louis International Airport...
, Whiteman Air Force BaseWhiteman Air Force BaseWhiteman Air Force Base is a United States Air Force base located approximately south of Knob Noster, Missouri; east-southeast of Kansas City, Missouri....
(Missouri Air National Guard)- 110th Bomb Squadron110th Fighter SquadronThe 110th Bomb Squadron flies the B-2 Spirit. It is a unit of the Missouri Air National Guard. Its parent organization is the 131st Bomb Wing.-Major Command:*Air National Guard/Air Force Global Strike Command...
- 110th Bomb Squadron
- 412th Test Wing412th Test WingThe 412th Test Wing is a wing of the United States Air Force, assigned to the Air Force Flight Test Center at Edwards Air Force Base, California.-Overview:...
, Edwards Air Force BaseEdwards Air Force BaseEdwards Air Force Base is a United States Air Force base located on the border of Kern County, Los Angeles County, and San Bernardino County, California, in the Antelope Valley. It is southwest of the central business district of North Edwards, California and due east of Rosamond.It is named in...
(currently has one B-2)- 419th Flight Test Squadron419th Flight Test SquadronThe 419th Flight Test Squadron is part of the 412th Test Wing and is based at Edwards Air Force Base, California. It performs flight testing on B-1 Lancer, B-52 Stratofortress, F-15 Eagle, F-16 Fighting Falcon, and EA-6B Prowler aircraft as well as Advanced Cruise Missiles.-History:Established as...
- 419th Flight Test Squadron
- 53d Wing53d WingThe 53d Wing is a wing of the United States Air Force based out of Eglin Air Force Base, Florida.-Mission:The 53d Wing serves as the focal point for the Combat Air Forces in electronic warfare, armament and avionics, chemical defense, reconnaissance, and aircrew training devices...
, Eglin Air Force BaseEglin Air Force BaseEglin Air Force Base is a United States Air Force base located approximately 3 miles southwest of Valparaiso, Florida in Okaloosa County....
(former)- 72d Test and Evaluation Squadron72d Test and Evaluation SquadronThe 72d Test and Evaluation Squadron is part of the 53d Wing at Eglin Air Force Base, Florida. The squadron is geographically separated but operated from Whiteman Air Force Base, Missouri...
, Whiteman Air Force BaseWhiteman Air Force BaseWhiteman Air Force Base is a United States Air Force base located approximately south of Knob Noster, Missouri; east-southeast of Kansas City, Missouri....
- 72d Test and Evaluation Squadron
- 57th Wing57th WingThe 57th Wing is an operational unit of the United States Air Force Warfare Center, stationed at Nellis Air Force Base, Nevada.The 57 WG's mission is to provide well trained and well equipped combat forces ready to deploy into a combat arena to conduct integrated combat operations.-Mission:The 57...
, Nellis Air Force BaseNellis Air Force BaseNellis Air Force Base is a United States Air Force Base, located approximately northeast of Las Vegas, Nevada. It is under the jurisdiction of Air Combat Command .-Overview:...
(former)- 325th Weapons Squadron325th Weapons SquadronThe 325th Weapons Squadron is a United States Air Force unit assigned to the USAF Weapons School, stationed at Whiteman Air Force Base, Missouri.The 325th WPS is a Geographically Separated Unit of the 57th Wing, assigned to Nellis AFB, Nevada...
, Whiteman Air Force BaseWhiteman Air Force BaseWhiteman Air Force Base is a United States Air Force base located approximately south of Knob Noster, Missouri; east-southeast of Kansas City, Missouri.... - 715th Weapons Squadron715th Weapons SquadronThe 715th Weapons Squadron is an inactive United States Air Force unit. It was last assigned to the USAF Weapons School at Whiteman Air Force Base, Missouri...
(inactivated)
- 325th Weapons Squadron
- 509th Bomb Wing
Accident
On 23 February 2008, the B-2 Spirit of Kansas, 89-0127 crashed on the runway shortly after takeoff from Andersen Air Force BaseAndersen Air Force Base
Andersen Air Force Base is a United States Air Force base located approximately northeast of Yigo in the United States territory of Guam....
in Guam
Guam
Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United...
. B-2 89-0127 had been operated by the 393rd Bomb Squadron, 509th Bomb Wing
509th Bomb Wing
The 509th Bomb Wing is a United States Air Force unit assigned to the Air Force Global Strike Command, Eighth Air Force. It is stationed at Whiteman Air Force Base, Missouri....
, Whiteman Air Force Base
Whiteman Air Force Base
Whiteman Air Force Base is a United States Air Force base located approximately south of Knob Noster, Missouri; east-southeast of Kansas City, Missouri....
, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
, and had logged 5,176 flight hours. It was the first crash of a B-2. The two person crew ejected safely from the aircraft and survived the crash. The aircraft was completely destroyed, a hull loss
Aviation accidents and incidents
An aviation accident is defined in the Convention on International Civil Aviation Annex 13 as an occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight and all such persons have disembarked, in which a...
valued at US$1.4 billion. After the accident, the Air Force took the B-2 fleet off operational status until clearing the fleet for flight status 53 days later on 15 April 2008. The cause of the crash was later determined to be moisture in the aircraft's Port Transducer Units during air data calibration, which distorted the information being sent to the bomber's air data system. As a result, the flight control computers calculated an inaccurate airspeed, and a negative angle of attack, causing the aircraft to pitch upward 30 degrees during takeoff.
Aircraft on display
Strategic bombing
Strategic bombing is a military strategy used in a total war with the goal of defeating an enemy nation-state by destroying its economic ability and public will to wage war rather than destroying its land or naval forces...
role, and the still-classified aspects of its low observable coatings, no production B-2 has been placed on permanent display. However, B-2s have made periodic appearances on ground display at various air show
Air show
An air show is an event at which aviators display their flying skills and the capabilities of their aircraft to spectators in aerobatics. Air shows without aerobatic displays, having only aircraft displayed parked on the ground, are called "static air shows"....
s.
- B-2 test article (s/n AT-1000), the second of two built without engines or instruments for static testing, was placed on display in 2004 at the National Museum of the United States Air ForceNational Museum of the United States Air ForceThe National Museum of the United States Air Force is the official museum of the United States Air Force located at Wright-Patterson Air Force Base northeast of Dayton, Ohio. The NMUSAF is the world's largest and oldest military aviation museum with more than 360 aircraft and missiles on display...
near DaytonDayton, OhioDayton is the 6th largest city in the U.S. state of Ohio and the county seat of Montgomery County, the fifth most populous county in the state. The population was 141,527 at the 2010 census. The Dayton Metropolitan Statistical Area had a population of 841,502 in the 2010 census...
, Ohio. The test article passed all structural testing requirements before the airframe failed. The Museum's restoration team spent over a year reassembling the fractured airframe. The display airframe is marked to resemble The Spirit of Ohio (S/N 82-1070), the B-2 used to test the design's ability to withstand extreme heat and cold. The exhibit features the actual Spirit of Ohio nose wheel door, with its distinctive Fire and Ice artwork, which was painted and signed by the technicians who performed the temperature testing. The restored test aircraft is on display in the museum's "Cold War Gallery".
- From 1989 to 2004, the South Dakota Air and Space MuseumSouth Dakota Air and Space MuseumThe South Dakota Air and Space Museum, part of the museum system of the National Museum of the US Air Force, is located in Box Elder, South Dakota, just outside the main gate of Ellsworth AFB. The South Dakota Air and Space Museum serves to educate and entertain the public...
located on the grounds of Ellsworth Air Force BaseEllsworth Air Force BaseEllsworth Air Force Base is a United States Air Force base located approximately northeast of Rapid City, South Dakota just north of Box Elder, South Dakota....
displayed the 10-short-ton (9-metric-ton) "Honda- Stealth", a 60% scale mock-up of a stealthy bomber which had been built by North American HondaHondais a Japanese public multinational corporation primarily known as a manufacturer of automobiles and motorcycles.Honda has been the world's largest motorcycle manufacturer since 1959, as well as the world's largest manufacturer of internal combustion engines measured by volume, producing more than...
in 1988 for an advertising campaignAdvertising campaignAn advertising campaign is a series of advertisement messages that share a single idea and theme which make up an integrated marketing communication...
. Although not an actual replica of a B-2, the mock-up was close enough to the B-2's design to arouse suspicion that Honda had intercepted classified, top secretTop SecretTop Secret generally refers to the highest acknowledged level of classified information.Top Secret may also refer to:- Film and television :* Top Secret , a British comedy directed by Mario Zampi...
information, as the B-2 project was still officially classified in 1988. Honda donated the model to the museum in 1989, on condition that the model be destroyed if it was ever replaced with a different example. In 2005, when the museum received a B-1 Lancer for display (Ellsworth being a B-1 base), the museum destroyed the mock-up.
Specifications (B-2A Block 30)
Later avionics and equipment improvements allow B-2A to carry JSOW, GBU-28
GBU-28
The Guided Bomb Unit 28 is a 5,000 pound laser-guided "bunker busting" bomb nicknamed "Deep Throat" produced originally by the Watervliet Arsenal, Watervliet, New York. It was designed, manufactured, and deployed in less than three weeks due to an urgent need during Operation Desert Storm to...
, and GBU-57A/Bs as well. The Spirit is also designated as a delivery aircraft for the AGM-158 JASSM
AGM-158 JASSM
The AGM-158 JASSM is a low observable standoff cruise missile developed in the United States. It is a large, semi-stealthy long-range weapon of the class. The missile's development began in 1995, but a number of problems during testing delayed its introduction into service until 2009...
when the missile enters service.
Individual aircraft
| Air Vehicle No. | Block No. | USAF s/n | Formal name | Status |
|---|---|---|---|---|
| AV-1 | Test/30 | 82-1066 | Spirit of America | 14 July 2000 – Active |
| AV-2 | Test/30 | 82-1067 | Spirit of Arizona | 4 December 1997 – Active |
| AV-3 | Test/30 | 82-1068 | Spirit of New York | 10 October 1997 – Active, Flight Test |
| AV-4 | Test/30 | 82-1069 | Spirit of Indiana | 22 May 1999 – Active |
| AV-5 | Test/20 | 82-1070 | Spirit of Ohio | 18 July 1997 – Active |
| AV-6 | Test/30 | 82-1071 | Spirit of Mississippi | 23 May 1997 – Active |
| AV-7 | 10 | 88-0328 | Spirit of Texas | 21 August 1994 – Active |
| AV-8 | 10 | 88-0329 | Spirit of Missouri | 31 March 1994 – Active |
| AV-9 | 10 | 88-0330 | Spirit of California | 17 August 1994 – Active |
| AV-10 | 10 | 88-0331 | Spirit of South Carolina | 30 December 1994 – Active |
| AV-11 | 10 | 88-0332 | Spirit of Washington | 29 October 1994 – Active |
| AV-12 | 10 | 89-0127 | Spirit of Kansas | 17 February 1995 – 23 February 2008, Crashed |
| AV-13 | 10 | 89-0128 | Spirit of Nebraska | 28 June 1995 – Active |
| AV-14 | 10 | 89-0129 | Spirit of Georgia | 14 November 1995 – Active |
| AV-15 | 10 | 90-0040 | Spirit of Alaska | 24 January 1996 – Active |
| AV-16 | 10 | 90-0041 | Spirit of Hawaii | 10 January 1996 – Active |
| AV-17 | 20 | 92-0700 | Spirit of Florida | 3 July 1996 – Active |
| AV-18 | 20 | 93-1085 | Spirit of Oklahoma | 15 May 1996 – Active |
| AV-19 | 20 | 93-1086 | Spirit of Kitty Hawk | 30 August 1996 – Active |
| AV-20 | 30 | 93-1087 | Spirit of Pennsylvania | 5 August 1997 – Active |
| AV-21 | 30 | 93-1088 | Spirit of Louisiana | 10 November 1997 – Active |
| AV-22 through AV-165 | Canceled | |||
Sources: FAS.org, B-2 Spirit (Pace)
See also
Further reading
- Richardson, Doug. Northrop B-2 Spirit (Classic Warplanes). New York: Smithmark Publishers Inc., 1991. ISBN 0-8317-1404-2.
- Sweetman, BillBill SweetmanBill Sweetman is a former editor for Jane's and currently an editor for Aviation Week group. He is a writer of more than 50 books on military aircraft. He lives in Oakdale, Minnesota. He is noted for his dogged pursuit of the Aurora project...
. Inside the Stealth Bomber. St. Paul, Minnesota: MBI Publishing, 1999. ISBN 0-7603-0627-3. - Winchester, Jim, ed. "Northrop B-2 Spirit". Modern Military Aircraft (Aviation Factfile). Rochester, Kent, UK: Grange Books plc, 2004. ISBN 1-84013-640-5.
- The World's Great Stealth and Reconnaissance Aircraft. New York: Smithmark, 1991. ISBN 0-8317-9558-1.
External links
- B-2 Spirit fact sheet and gallery on U.S. Air Force site
- B-2 Spirit page on Northrop Grumman site
- B-2 page on NASA Langley site
- B-2 Spirit page at GlobalSecurity.org
- B-2 Bomber page on Center for Defense Information site
- B-2 Spirit Stealth bomber on airforce-technology.com
- B-2 Spirit (Stealth Bomber) page on aircraft-info.net
- B-2 Stealth Bomber article on How It Works Daily