B-2 Spirit
From Wikipedia, the free encyclopedia
| B-2 Spirit | |
|---|---|
 A USAF B-2 Spirit in flight. |
|
| Type | Stealth bomber |
| National origin | United States |
| Manufacturer | Northrop Corporation Northrop Grumman |
| Maiden flight | 17 July 1989 |
| Introduction | April 1997 |
| Status | Active service: 20 aircraft |
| Primary user | United States Air Force |
| Number built | 21[1][2] |
| Unit cost | $737 million to $2.2 billion[3] |
The Northrop Grumman B-2 Spirit is a multi-role stealth heavy bomber, capable of deploying both conventional and nuclear weapons. It is operated exclusively by the United States Air Force. Its development was a milestone in the modernization program of the U.S. Department of Defense. The B-2's stealth technology is intended to aid the aircraft's penetration role in order to survive extremely dense anti-aircraft defenses otherwise considered impenetrable by combat aircraft.
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[edit] Development
The B-2 started life as a black project known as the High Altitude Penetrating Bomber (HAPB), then became the Advanced Technology Bomber (ATB), which became the B-2 Spirit. The bomber's design was changed in the mid-1980s when its 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 $1 billion to the program's cost.[4] An estimated US$23 billion was secretly spent for research and development on the B-2 in the 1980s.[citation needed] At the program's peak, 13000 people were employed at a dedicated plant in Pico Rivera, California for the plane's engineering and some manufacturing.[5]
The first B-2 was publicly displayed on 22 November 1988, when it was rolled out of its hangar at Air Force Plant 42, Palmdale, California, where it was built. Its first public flight was on 17 July 1989. The B-2 Combined Test Force, Air Force Flight Test Center, Edwards Air Force Base, California, is responsible for flight testing the engineering, manufacturing and development aircraft.
The original procurement of 132 aircraft was later reduced to 75 in the late 1980s. In his 1992 State of the Union Address, President George H.W. Bush announced total B-2 production would be limited to 20 aircraft, with a total inventory of 21 by upgrading the first test aircraft to B-2A Block 30 standard.[6] This reduction was largely a result of the disintegration of the Soviet Union, which effectively rendered void the Spirit's primary mission.
The cost of the B-2 program in 1994 dollars was reported at $737 million per plane; however, the total cost of the program with development, spares, and facilities averaged over $2.1 billion per plane as of 1997 according to the B-2 program office.[3]
In 1990, the Department of Defense accused Northrop of using faulty components in the flight control system. More recent issues with the jet have included cracks in the tail, and efforts to reduce the probability that the engines will suck birds into the jet intakes, damaging fan blades.[7]
Northrop made a proposal to the USAF in the late 1990s to build additional aircraft for approximately $550M each. This more accurately reflects the per aircraft cost if the full order had been manufactured. The high development costs included: another stealth prototype (now at the USAF museum), security costs which included inefficiencies of separating design teams, the development of a computer aided design system which requires no paper (it was the first aircraft so designed), a totally computerized manufacturing control system (the first of its kind), and a computerized maintenance system to help crew chiefs.[citation needed]
[edit] Design
As with the B-52 Stratofortress and 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. In addition, its low-observable, or "stealth," characteristics give it the ability to penetrate an enemy's most sophisticated defenses and attack its most heavily defended targets.
The blending of low-observable technologies with high aerodynamic efficiency and large payload gives the B-2 significant advantages over previous bombers. Its range is approximately 6,000 nautical miles (11,100 km) without refueling. Also, its low-observation ability provides the B-2 greater freedom of action at high altitudes, thus increasing its range and giving 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 "dumb" 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 bombs, or as many as 80 when carrying 500-lb bombs.
The B-2's stealth comes from a combination of reduced acoustic, infrared, visual and radar signatures, making it difficult for defenses to detect, track and engage. Many specific aspects of the low-observability process remain classified; however, the B-2 represents a further advancement of technology exploited for the F-117. Pyotr Ufimtsev, whose theoretical work made the F-117 and B-2 possible, was hired by Northrop at one time. Additionally, the B-2's composite materials, special coatings and flying wing design (which cuts down on the number of leading edges) contribute to its stealth abilities.[8] The B-2 uses radar absorbent material and coatings that require climate-controlled hangars for maintenance.[9] The engines are contained within the wing contour and just above the wing, helping scatter radar reflections and hide their exhaust.[10]
The B-2 has a crew of two; a pilot in the left seat and mission commander in the right.[11] The B-2 has a provision for a third crew member if required in the future.[12] For comparison, the B-1B has a crew of four and the B-52 has a crew of five.[11] B-2 crews have been used to pioneer sleep cycle research to improve crew performance on long flights. The B-2 is highly automated, and unlike single-seat fighters, one crew member can sleep, use a flush toilet or prepare a hot meal while the other monitors the aircraft.[13]
[edit] Operational history
The first operational aircraft, christened Spirit of Missouri, was delivered on December 17, 1993. The B-2 fleet is based at Whiteman Air Force Base in Missouri. Depot maintenance for the B-2 is accomplished by United States Air Force contractor support and managed at the Oklahoma City Air Logistics Center, Tinker Air Force Base, Oklahoma.[11] Originally designed to deliver nuclear weapons, modern usage has shifted towards a flexible role with conventional and nuclear capability.
The prime contractor, responsible for overall system design and integration, is Northrop Grumman Integrated Systems Sector. Boeing Integrated Defense Systems, Hughes Aircraft (now Raytheon), General Electric Aircraft Engines and Vought Aircraft Industries, are members of the aircraft contractor team. Another contractor, responsible for aircrew training devices (weapon system trainer and mission trainer) is Link Simulation & Training, a division of L-3 Communications formerly Hughes Training Inc. (HTI).[14] Link Division, formerly known as CAE - Link Flight Simulation Corp. Link Simulation & Training is responsible for developing and integrating all aircrew and maintenance training programs.
[edit] Combat
The B-2 has seen service in three separate campaigns. Its debut was during the Kosovo War in 1999. The B-2 first introduced the satellite guided JDAM in combat use. Since then, the aircraft has operated over Afghanistan in Operation Enduring Freedom and Iraq in Operation Iraqi Freedom. During the Iraq campaign, B-2s were temporarily operated from Diego Garcia. Later missions to Iraq launched from Whiteman Air Force Base in Missouri. This resulted in missions lasting over 30 hours and one mission of over 50 hours.
The Pentagon's Operational Test and Evaluation 2003 Annual Report noted that the B-2's serviceability for FY03 was still inadequate, mainly due to maintenance on the B-2's Low Observable materials. The evaluation also noted that the Defensive Avionics suite also had shortcomings with pop-up threats.[15] Despite these problems the B-2 reached full operational capability in December 2003.[11] The B-2 maintained high mission capable rates for Operation Iraqi Freedom, dropping 583 JDAMs during the campaign.[16]
[edit] Recent events
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. His trial was initially scheduled for 12 February 2008, but he received a continuance.[17][18] In 1984 a Northrop employee, Thomas Cavanagh, was arrested for trying to sell secrets apparently smuggled out of the Pico Rivera plant to the Soviet Union and was eventually sentenced to life in prison.[19]
The USAF has funded a project to upgrade the B-2s weapon control systems so new weapons can be used, including weapons intended to hit moving targets. [20]
[edit] Operators
- United States Air Force
- 509th Bomb Wing, Whiteman Air Force Base (Current, 19 aircraft)
- 13th Bomb Squadron
- 393d Bomb Squadron
- 394th Combat Training Squadron
- 412th Test Wing, Edwards Air Force Base (Current, one aircraft)
- 419th Flight Test Squadron, Edwards Air Force Base
- 53d Wing, Eglin Air Force Base (past)
- 72d Test and Evaluation Squadron, Whiteman Air Force Base
- 57th Wing, Nellis Air Force Base (past)
- 325th Weapons Squadron, Whiteman Air Force Base
- 715th Weapons Squadron (inactivated)
- 509th Bomb Wing, Whiteman Air Force Base (Current, 19 aircraft)
[edit] Incidents and accidents
On 23 February 2008, B-2 s/n 89-0127, named Spirit of Kansas, crashed onto the runway shortly after takeoff from Andersen Air Force Base in Guam.[21] The crash of the Spirit of Kansas, which had 5,100 flight hours, was the first ever for the B-2. Both pilots ejected before the crash and survived, but the aircraft was completely destroyed, at an estimated loss of US $1.4B.[22] No munitions were on board because it and three other B-2s were returning to Whiteman Air Force Base from a temporary deployment to Guam. [23] At Guam Naval Hospital, one pilot was evaluated and released, while the second remained hospitalized. A B-2 already in the air was called back to Andersen following the crash, where it and the other B-2s were grounded until an initial investigation into the crash was complete. Six B-52s of the 96th Bomb Squadron, 2d Bomb Wing at Barksdale Air Force Base, Louisiana were deployed to replace the B-2s.[24][25] Chief of Air Combat Command General John Corley stated that the B-2 "rotated early, rotated excessively, stalled, and then dragged the left wingtip". The pilots then ejected and the aircraft ran off the side of the runway and burned.[26]
The commander of the 509th Bomb Wing, Brig. Gen. Garrett Harencak, followed up on the incident by temporarily suspending flying operations for all 20 remaining B-2s to review procedures. Harencak termed the suspension a "safety pause" and stated that the B-2s would resume flying if called upon for immediate operations.[27] The B-2 returned to flight on 15 April 2008.[28]
The findings of the subsequent investigation stated that the B-2 crashed after water distorted preflight readings in three of the plane's 24 sensors, making the aircraft's control computer force the B-2 to pitch up on takeoff, causing the aircraft to stall and subsequently crash.[29] [30][31] The sensors in question measure numerous environmentals, such as air pressure, and help calculate everything from airspeed to altitude. Because of the bad data resulting from the distortions, the flight computers had inaccurate airspeed readings, and incorrectly indicated a downward angle for the aircraft, which contributed to an early rotation and an uncontrolled 30-degree pitch up, resulting in the stall.[32]
[edit] B-2 on display
Because of its cost, rarity, and combat value, no production B-2 has been placed on permanent display. However, B-2s have made periodic appearances on ground display at various air shows.
In 2004, one of test articles (s/n AT-1000) built without engines or instruments for static testing was placed on display at the National Museum of the United States Air Force near Dayton, Ohio.[33] The test article had been used for structural testing, and after passing all planned tests, pressure was applied until the right wing broke off at 161% of specification.[34] The Museum's restoration team spent over a year reassembling the fractured airframe.
From 1989 to 2004, the South Dakota Air and Space Museum located on the grounds of Ellsworth Air Force Base displayed the 10-ton (9.1 tonne) "Honda Stealth", a 60% scale mock-up of a stealth bomber, which had been built by North American Honda in 1988 for a national automobile campaign.[35] Although not an actual replica of a B-2, the mock-up was close enough to create a stir that Honda had cracked national security, as the B-2 project was still officially classified in 1988. Honda donated the model to the Museum in 1989, on the condition that the model be destroyed if it were ever replaced with a different aircraft. In 2005, when the museum received a B-1 Lancer for display (Ellsworth being a B-1 base), the Honda Stealth was cut up.[36][37]
[edit] Specifications (B-2A Block 30)
Data from Global Security[38]
General characteristics
- Crew: 2
- Length: 69 ft (21 m)
- Wingspan: 172 ft (52.4 m)
- Height: 17 ft (5.2 m)
- Wing area: 5,000 ft² (460 m²)
- Empty weight: 158,000 lb (71.7 t)
- Loaded weight: 336,500 lb (152.6 t)
- Max takeoff weight: 376,000 lb (171.0 t)
- Powerplant: 4× General Electric F118-GE-100 turbofans, 17,300 lbf (77 kN) each
Performance
- Maximum speed: 410 knots (760 km/h, 470 mph)
- Range: 5,600 nm (10,400 km, 6,400 mi)
- Service ceiling 50,000 ft (15,000 m)
- Wing loading: 67.3 lb/ft² (329 kg/m²)
- Thrust/weight: 0.205
Armament
- 2 internal bays for 50,000 lb (22,700 kg) of ordnance.[39]
Later avionics and equipment improvements allow B-2A to carry JSOW and GBU-28s as well. The Spirit is also designated as a delivery aircraft for the AGM-158 JASSM when the missile enters service.
[edit] List of B-2 bombers
| Air Vehicle No. | Block No.[40] | USAF s/n | Formal name | Status |
|---|---|---|---|---|
| AV-1 | Test | 82-1066 | Spirit of America | Active |
| AV-2 | Test | 82-1067 | Spirit of Arizona | Active |
| AV-3 | Test | 82-1068 | Spirit of New York | Active, Flight Test |
| AV-4 | Test | 82-1069 | Spirit of Indiana | Active |
| AV-5 | Test | 82-1070 | Spirit of Ohio | Active |
| AV-6 | Test | 82-1071 | Spirit of Mississippi | Active |
| AV-7 | 10 | 88-0328 | Spirit of Texas | Active |
| AV-8 | 10 | 88-0329 | Spirit of Missouri | Active |
| AV-9 | 10 | 88-0330 | Spirit of California | Active |
| AV-10 | 10 | 88-0331 | Spirit of South Carolina | Active |
| AV-11 | 10 | 88-0332 | Spirit of Washington | Active |
| AV-12 | 10 | 89-0127 | Spirit of Kansas | Crashed 23 February 2008[25] |
| AV-13 | 10 | 89-0128 | Spirit of Nebraska | Active |
| AV-14 | 10 | 89-0129 | Spirit of Georgia | Active |
| AV-15 | 10 | 90-0040 | Spirit of Alaska | Active |
| AV-16 | 10 | 90-0041 | Spirit of Hawaii | Active |
| AV-17 | 20 | 92-0700 | Spirit of Florida | Active |
| AV-18 | 20 | 93-1085 | Spirit of Oklahoma | Active |
| AV-19 | 20 | 93-1086 | Spirit of Kitty Hawk | Active |
| AV-20 | 30 | 93-1087 | Spirit of Pennsylvania | Active |
| AV-21 | 30 | 93-1088 | Spirit of Louisiana | Active |
| AV-22/AV-165 cancelled | ||||
- Source: FAS.org[41]
[edit] See also
Related development
Related lists
[edit] References
[edit] Notes
- ^ National Museum of the United States Air Force Northrop B-2A Spirit fact sheet
- ^ AIR FORCE Magazine: 2007 Almanac; Gallery of Weapons
- ^ a b United States General Accounting Office (GAO) B-2 Bomber: Cost and Operational Issues (Letter Report, 08/14/97, GAO/NSIAD-97-181).
- ^ Goodall, James C. "The Northrop B-2A Stealth Bomber", America's Stealth Fighters and Bombers, B-2, F-117, YF-22, and YF-23. MBI Publishing Company, 1992. ISBN 0-87938-609-6.
- ^ Pico Rivera
- ^ President George H. Bush's State of the Union Address, 28 January 1992.
- ^ "Moisture in sensors led to stealth bomber crash, Air Force report says", Kansas City Star, June 5, 2008
- ^ B-2, Encyclopedia.com
- ^ Fulghum, D.A. "Away Game". Aviation Week & Space Technology, 8 January 2007. "First F-22 large-scale, air combat exercise wins praise and triggers surprise" (online title).
- ^ B-2 page, Aerospaceweb.org.
- ^ a b c d B-2 USAF fact sheet
- ^ B-2 Spirit page, Northrop Grumman
- ^ Tirpak, John A. "With the First B-2 Squadron." Air Force Magazine: Journal of the Air Force Association, Vol. 79, No. 4., April 1996.
- ^ B-2 Aircrew Training System
- ^ Pop-up is an informative call of a contact that has suddenly appeared inside of meld/CCR/briefed range.
- ^ Air Force programs: B-2
- ^ FBI Honolulu Press Release
- ^ Gowadia case
- ^ No Headline - New York Times
- ^ Northrop Grumman Corporation: "Precision-Guided Weapons Could Allow Aircraft to Attack Multiple Moving Ground Targets in Adverse Weather From Stand-Off Ranges" Feb. 7, 2008
- ^ B-2 stealth bomber crashes on Guam, Yahoo! News, 23 February 2008.
- ^ Air Force: Moisture caused $1.4 billion bomber crash. CNN.com (June 6, 2008). Retrieved on 2008-06-07.
- ^ No munitions on board B-2 that crashed, Air Force Times, 23 February 2008.
- ^ Stealth bomber crashes on Guam
- ^ a b Lavitt, Michael O. "B-2 Crashes on Takeoff From Guam", Aviation Week, February 23, 2008.
- ^ "News Breaks." Aviation Week and Space Technology, 31 March 2008, pp. 18-19.
- ^ B-2 flights suspended following crash
- ^ Linch, Stephen. "B-2s return to flight after safety pause", USAF, 21 April 2008.
- ^ "Air Force: Sensor moisture caused 1st B-2 crash", MSNBC, June 5, 2008'
- ^ "Moisture confused sensors in B-2 crash", AirForceTimes, 6 June 2008.
- ^ http://blog.wired.com/defense/2008/06/video-stealth-b.html
- ^ "B2 Stealth Bomber Crashes"
- ^ The display airframe is marked to resemble B-2 82-1070, The Spirit of Ohio, and has the original Fire and Ice nose wheel door from the actual bomber.
- ^ National Museum of the USAF B-2 fact page
- ^ "Honda Stealth"
- ^ Museum slices stealth display
- ^ B-1 to go on display in museum
- ^ B-2 specifications, GlobalSecurity.com All 21 aircraft were upgraded to Block 30 standard.
- ^ Spick 2000, p. 340.
- ^ All 21 copies brought to Block 30 standard.
- ^ B-2 page on fas.org
[edit] Bibliography
- CNN - B-2 stealth bombers make combat debut - 24 March 1999
- Donald, David, ed. Black Jets: The Development and Operation of America's Most Secret Warplanes. Norwalk, Connecticut: AIRtime Publishing Inc., 2003. ISBN 1-880588-67-6.
- Richardson, Doug. Northrop B-2 Spirit (Classic Warplanes). New York: Smithmark Publishers Inc., 1991. ISBN 0-8317-1404-2.
- Spick, Mike. The Great Book of Modern Warplanes. St. Paul, Minnesota: MBI Publishing Company, 2000. ISBN 0-7603-0893-4.
- 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.
[edit] External links
- USAF Fact sheet on B-2 Spirit
- B-2 Spirit page on NorthropGrumman.com
- B-2 page on NASA Langley site
- B-2 Spirit page on GlobalSecurity.org
- B-2 Bomber page on Center for Defense Information web site
- B-2 Operational Test and Evaluation 2003 Annual Report
- B-2 Spirit Stealth bomber on airforce-technology.com
- B-2 Spirit (Stealth Bomber) page on Aircraft-Info.net
- B-2 Spirit Stealth Bomber gallery page on bugimus.com
- Stealth Bomber crash video on LiveLeak.com
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