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Sunday, November 23, 2014

Northrop B2 Spirit

Here are some images of Testors 1/72 scale B2 Spirit stealth bomber.

From Wikipedia"

The Northrop (later Northrop Grumman) B-2 Spirit, also known as the Stealth Bomber, is an American strategic bomber, featuring low observable stealth technology designed for penetrating dense anti-aircraft defenses; it is able to deploy both conventional and nuclear weapons. The bomber has a crew of two and can drop up to eighty 500 lb (230 kg)-class JDAM GPS-guided bombs, or sixteen 2,400 lb (1,100 kg) B83 nuclear bombs. 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 his reasons for the cancellation of the supersonic Rockwell 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, 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 including development, engineering and testing, averaged $2.1 billion per aircraft in 1997.
Because of its considerable capital and operating costs, the project was controversial in the U.S. Congress and among the Joint Chiefs of Staff. The winding-down of the Cold War in the latter portion of the 1980s dramatically reduced the need for the aircraft, which was designed with the intention of penetrating Soviet airspace and attacking high-value targets. During the late 1980s and 1990s, Congress slashed plans to purchase 132 bombers to 21. In 2008, a B-2 was destroyed in a crash shortly after takeoff, though the crew ejected safely. A total of 20 B-2s remain in service with the United States Air Force, who plan to operate the B-2 until 2058.
The B-2 is capable of all-altitude attack missions up to 50,000 feet (15,000 m), with a range of more than 6,000 nautical miles (11,000 km) on internal fuel and over 10,000 nautical miles (19,000 km) with one midair refueling. Though originally designed primarily as a nuclear bomber, it was first used in combat dropping conventional ordnance in the Kosovo War in 1999 and saw further service in Iraq and Afghanistan.

In the mid-1970s, the search for a new U.S. strategic bomber aircraft to replace the Boeing B-52 Stratofortress was underway, to no avail. First the B-70 and then the B-1A were canceled after only prototypes of each aircraft were built. The B-70 was intended to fly above and beyond defensive interceptor aircraft, only to find these same attributes made it especially vulnerable to surface-to-air missiles (SAMs). The B-1 attempted to avoid SAMs by flying close to the ground to use terrain to mask its radar signature, only to face a new generation of interceptors with look-down/shoot-down capabilities that could attack them from above.
By the mid-1970s, it was becoming clear that there was a different way to avoid missiles and intercepts; known today as "stealth"; the concept was to build an aircraft with an airframe that deflected or absorbed radar signals so that little was reflected back to the radar unit. An aircraft having stealth characteristics would be able to fly nearly undetected and could be attacked only by weapons and systems not relying on radar. Although such possibilities existed, such as human observation, their relatively short detection range allowed most aircraft to fly undetected by defenses, especially at night.
In 1974, DARPA requested information from U.S. aviation firms about the largest radar cross-section of an aircraft that would remain effectively invisible to radars. Initially, Northrop and McDonnell Douglas were selected for further development. Lockheed had experience in this field due to developing the Lockheed A-12 and SR-71, which included a number of stealthy features, notably its canted vertical stabilizers, the use of composite materials in key locations, and the overall surface finish in radar-absorbing paint. A key improvement was the introduction of computer models used to predict the radar reflections from flat surfaces where collected data drove the design of a "faceted" aircraft. Development of the first such designs started in 1975 with "the hopeless diamond", a model Lockheed built to test the concept.
Plans were well advanced by the summer of 1975, when DARPA started the Experimental Survivability Testbed (XST) project. Northrop and Lockheed were awarded contracts in the first round of testing. Lockheed received the sole award for the second test round in April 1976 leading to the Have Blue program.

By 1976, these programs progressed to where a long-range strategic stealth bomber appeared viable. President Carter was aware of these developments during 1977, and it appears to have been one of the major reasons the B-1 was canceled. Further studies were ordered in early 1978, by which point the Have Blue platform had flown and proven the concepts. During the 1980 presidential election in 1979, Ronald Reagan repeatedly stated that Carter was weak on defense, and used the B-1 as a prime example. In return, on 22 August 1980, the Carter administration publicly disclosed that the United States Department of Defense (DoD) was working to develop stealth aircraft, including a bomber.
Front view of tailless aircraft parked in front of building. On the building face is a blue and red rectangular flag. In the foreground is a star shape on the ground
The B-2's first public display in 1988
The Advanced Technology Bomber (ATB) began in 1979. Full development of the black project followed, and was funded under the code name "Aurora". After the evaluations of the companies' proposals, the ATB competition was narrowed 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 prior experience developing the YB-35 and YB-49 flying wing aircraft. The Northrop design was larger while the Lockheed design included a small tail. In 1979, designer Hal Markarian produced a sketch of the aircraft, that bore considerable similarities to the final design. The Air Force originally planned to procure 165 of the ATB bomber.
The Northrop 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. MIT engineers and scientists helped assess the mission effectiveness of the aircraft under a five-year classified contract during the 1980s.

Both during development and in service, there has been considerable importance placed to the security of the B-2 and its technologies. Staff working on the B-2 in most, if not all, capacities have to achieve a level of special-access clearance, and undergo extensive background checks carried out by a special branch of the Air Force.
For the manufacturing, a former Ford automobile assembly plant in Pico Rivera, California, was acquired and heavily rebuilt; the plant's employees were sworn to complete secrecy regarding their work. To avoid the possibility of suspicion, components were typically purchased through front companies, military officials would visit out of uniform, and staff members were routinely subjected to polygraph examinations. The secrecy extended so far that access to nearly all information on the program by both Government Accountability Office (GAO) and virtually all members of Congress itself was severely limited until mid-1980s. Northrop (now Northrop Grumman) was the B-2's prime contractor; major subcontractors included Boeing, Hughes Aircraft (now Raytheon), GE, and Vought Aircraft.
In 1984, a Northrop employee, Thomas Cavanaugh was arrested for attempting to sell classified information to the Soviet Union; the information was taken from Northrop's Pico Rivera, California factory. Cavanaugh was eventually sentenced to life in prison and released on parole in 2001.
The B-2 was first publicly displayed on 22 November 1988 at Air Force Plant 42, Palmdale, California, where it was assembled. This viewing was heavily restricted, and guests were not allowed to see the rear of the B-2. However, Aviation Week editors found that there were no airspace restrictions above the presentation area and took photographs of the aircraft's then-secret planform and suppressed engine exhausts from the air, to the USAF's disappointment. The B-2's (s/n 82-1066 / AV-1) first public flight was on 17 July 1989 from Palmdale to Edwards AFB.
In October 2005, Noshir Gowadia, a design engineer who worked on the B-2's propulsion system, was arrested for selling B-2 related classified information to foreign countries. 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.

A procurement of 132 aircraft was planned in the mid-1980s, but was later reduced to 75. By the early 1990s, the Soviet Union dissolved, effectively eliminating 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 cost to American taxpayers. In 1996, the General Accounting Office (GAO) 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 (US$6.8 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, particularly 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 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. The B-2 may cost up to $135,000 per flight hour to operate in 2010, which is about twice that of the B-52 and B-1.

In its consideration of the fiscal year 1990 defense budget, the House Armed Services Committee trimmed $800 million from the B-2 research and development budget, while at the same time staving off a motion to end the project. 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 end the project, others in the Senate, such as Jim Exon (D-NE) and John McCain (R-AZ), also opposing the project.
The escalating 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 to continue the program. 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; the threat posed by bird ingestion potentially damaging engine fan blades also required redesigning.
In time, a number of prominent members of Congress began to oppose the program's expansion, including later Democratic presidential nominee John Kerry, who cast votes against the B-2 in 1989, 1991 and 1992 while a U.S. 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 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, and that the military had greater priorities in spending a limited budget.
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 expended munitions by less than US$2 billion in 1995 dollars during the first two weeks of a conflict, in which the Air Force predicted bombers would make their greatest contribution; 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.

A number of upgrade packages have been applied to the B-2. In July 2008, the B-2's onboard computing architecture was extensively redesigned; it now incorporates a new integrated processing unit (IPU) that communicates with systems throughout the aircraft via a newly installed fibre optic network; a new version of the operational flight program software was also developed, with legacy code converted from the JOVIAL programming language used beforehand to standard C. Updates were also made to the weapon control systems to enable strikes upon non-static targets, such as moving ground vehicles.
On 29 December 2008, Air Force officials awarded a US$468 million contract to Northrop Grumman to modernize the B-2 fleet's radars. Changing the radar's frequency was required as the U.S. Department of Commerce has sold that radio spectrum to another operator. In July 2009, it was reported that the B-2 had successfully passed a major USAF audit. In 2010, it was made public that the Air Force Research Laboratory had developed a new material to be used on the part of the wing trailing edge subject to engine exhaust, replacing existing material that quickly degraded.
In 2013 the USAF contracted for the Defensive Management System Modernization program to replace the antenna system and other electronics to increase the B-2's frequency awareness.
In July 2010, political analyst Rebecca Grant speculated that when the B-2 becomes unable to reliably penetrate enemy defenses, the Lockheed Martin F-35 Lightning II may take on its strike/interdiction mission, carrying B61 nuclear bombs as a tactical bomber. However, in March 2012, the Pentagon announced that a $2 billion, 10-year-long modernization of the B-2 fleet was to begin. The main area of improvement would be replacement of outdated avionics and equipment.
It was reported in 2011 that the Pentagon was evaluating an unmanned stealth bomber, characterized as a "mini-B-2", as a potential replacement in the near future. In 2012, Air Force Chief of Staff General Norton Schwartz stated the B-2's 1980s-era stealth would make it less survivable in future contested airspaces, so the USAF is to proceed with the Next-Generation Bomber despite overall budget cuts. The Next-Generation Bomber was estimated, in 2012, to have a projected overall cost of $55 billion.
The Common Very Low Frequency Receiver upgrade will allow the B-2s to use the same Very low frequency transmissions as the SSBNs so as to continue in the nuclear mission until the Mobile User Objective System is fielded.
In 2014 the USAF outlined a series of upgrades including nuclear warfighting, a new integrated processing unit, the ability to carry cruise missiles, and threat warning improvements.

The first operational aircraft, christened Spirit of Missouri, was delivered to Whiteman Air Force Base, 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's combat debut was in 1999, during the Kosovo War. 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 use of JDAMs and precision-guided munitions effectively replaced the controversial tactic of carpet-bombing, which had been harshly criticised due to it causing indiscriminate civilian casualties in prior conflicts, such as the 1991 Gulf War. On 7 May 1999, a B-2 dropped five JDAMs on a target building that was actually the Chinese Embassy, killing several staff.
The B-2 saw service in Afghanistan, striking ground targets in support of Operation Enduring Freedom. With aerial refueling support, the B-2 flew one of its longest missions to date from Whiteman Air Force Base, Missouri to Afghanistan and back. B-2s would be stationed in the Middle East as a part of a US military buildup in the region from 2003.
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 sorties in Iraq have launched from Whiteman AFB. As of September 2013 the longest combat mission has been 44.3 hours. "Forward operating locations" have been previously designated as Andersen Air Force Base in Guam and RAF Fairford in the United Kingdom, 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 1,500,000 pounds (680,000 kg) of munitions, including 583 JDAM "smart bombs" in 2003.
In response to organizational issues and high-profile mistakes made within the Air Force, all of the B-2s, along with the nuclear-capable B-52s and the Air Force's intercontinental ballistic missiles (ICBMs), were transferred to the newly formed Air Force Global Strike Command on 1 February 2010.
In March 2011, B-2s were the first U.S. 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. The B-2s flew directly from the U.S. mainland across the Atlantic Ocean to Libya; a B-2 was refueled by allied tanker aircraft four times during each round trip mission.
In August 2011, The New Yorker reported that prior to the May 2011 U.S. special forces raid into Abbottabad, Pakistan that resulted in the death of Osama bin Laden, U.S. officials had considered an airstrike by one or more B-2s as an alternative; an airstrike was rejected because of damage to civilian buildings in the area from using a bunker busting bomb. There were also concerns an airstrike would make it difficult to positively identify Bin Laden's remains and so concluding he was in fact dead would be difficult.
On 28 March 2013, two B-2s flew a round trip of 13,000 miles (20,800 km) from Whiteman Air Force base in Missouri to South Korea, dropping dummy ordnance on the Jik Do target range. The mission, part of the annual South Korean–United States military exercises, was the first time that B-2s overflew the Korean peninsula. Tensions between North and South Korea were high during and after the exercise, North Korea protested against the participation of the B-2s and made threats of retaliatory nuclear strikes against South Korea and the United States.



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