F-35 Lightning II


The Lockheed Martin F-35 Lightning II is a fifth-generation, single-seat, single-engine, stealth-capable military strike fighter, a multirole aircraft that can perform close air support, tactical bombing, and air defense missions. The F-35 has three different models; one is the conventional takeoff and landing variant, the second is short takeoff and vertical-landing variant, and the third is a carrier-based variant.

The F-35 is descended from the X-35, the product of the Joint Strike Fighter (JSF) program. Its development is being principally funded by the United States, with the United Kingdom, and other partner governments providing additional funding. It is being designed and built by an aerospace industry team led by Lockheed Martin with Northrop Grumman and BAE Systems as major partners. Demonstrator aircraft flew in 2000, with the first flight on 15 December 2006.

Development
JSF Program history

Main article: Joint Strike Fighter Program
Requirement
The JSF program was designed to replace the U.S. military's F-16, A-10, F/A-18 and AV-8B tactical fighter aircraft. To keep development, production, and operating costs down, a common design was planned in three variants that share 80% of their parts:
F-35A, conventional takeoff and landing (CTOL) variant.
F-35B, short-takeoff and vertical-landing (STOVL) variant.
F-35C, carrier-based CATOBAR (CV) variant.
The F-35 is intended to be the world's premier strike aircraft through 2040, with close- and long-range air-to-air capability second only to that of the F-22 Raptor. The F-35 is required to be four times more effective than existing fighters in air-to-air combat, eight times more effective in air-to-ground battle combat, and three times more effective in reconnaissance and suppression of air defenses — all while having better range and require less logistics support.
With takeoff weights up to 60,000 lb (27,000 kg), the F-35 is considerably heavier than the lightweight fighters it replaces. In empty and maximum gross weights, it more closely resembles the single-seat, single-engine F-105 Thunderchief which was the largest single-engine fighter of the Vietnam era.

Origins and selection
The Joint Strike Fighter evolved out of several requirements for a common fighter to replace existing types. The actual JSF development contract was signed on 16 November 1996.
The contract for System Development and Demonstration (SDD) was awarded on 26 October 2001 to Lockheed Martin, whose X-35 beat the Boeing X-32. According to Department of Defense officials and British Minister of Defence Procurement Lord Bach, the X-35 consistently outperformed the X-32, although both met or exceeded requirements. The designation of the fighter as "F-35" came as a surprise to Lockheed, which had been referring to the aircraft in-house by the designation "F-24".

Design phase
The F-35 was in danger of missing performance requirements in 2004 because it weighed too much — reportedly, by 2,200 pounds (1,000 kg) or 8 percent. In response, Lockheed Martin added engine thrust and shed more than a ton by thinning the aircraft's skin; shrinking the weapons bay and vertical tails; rerouting some thrust from the roll-post outlets to the main nozzle; and redesigning the wing-mate joint, portions of the electrical system, and the portion of the aircraft immediately behind the cockpit.

On 7 July 2006, the U.S. Air Force officially announced the name of the F-35: Lightning II, in honor of Lockheed's World War II-era twin-prop P-38 Lightning and the Cold War-era jet, the English Electric Lightning. English Electric Company's aircraft division was incorporated into BAC, a predecessor of F-35 partner BAE Systems. Other names previously listed as contenders were Kestrel, Phoenix, Piasa, Black Mamba and Spitfire II. Lightning II was also an early company name for the aircraft that became the F-22 Raptor.

On 6 April 2009 US Secretary of Defense Robert Gates announced that the US would buy a total of 2,443 JSFs.

On 21 April 2009 media reports, citing Pentagon sources, said that during 2007 and 2008, computer spies managed to copy and siphon off several terabytes of data related to F-35's design and the electronics systems, potentially enabling the development of defense systems against the aircraft. However, Lockheed Martin has rejected suggestions that the project has been compromised, saying that it "does not believe any classified information had been stolen".

Design
The F-35 appears to be a smaller, slightly more conventional, one-engine sibling of the sleeker, twin-engine F-22 Raptor, and indeed drew elements from it. The exhaust duct design was inspired by the General Dynamics Model 200, a 1972 VTOL aircraft designed for the Sea Control Ship. Lockheed teamed with the Yakovlev Design Bureau, developer of the Yakovlev Yak-141 "Freestyle", in the 1990s. Stealth technology makes the aircraft difficult to detect as it approaches short-range tracking radar.

Some improvements over current-generation fighter aircraft are:
Durable, low-maintenance stealth technology;
Integrated avionics and sensor fusion that combine information from off- and onboard sensors to increase the pilot's situational awareness and improve identification and weapon delivery, and to relay information quickly to other command and control (C2) nodes;
High speed data networking including IEEE 1394b and Fibre Channel.

Cockpit
The F-35 features a full-panel-width "panoramic cockpit display (PCD)", with dimensions of 20 by 8 inches (50 by 20 centimeters). A cockpit speech-recognition system (Direct Voice Input) is planned to improve the pilot's ability to operate the aircraft over the current-generation. The F-35 will be the first U.S. operational fixed-wing aircraft to use this system, although similar systems have been used in AV-8B and trialled in previous U.S. jets, particularly the F-16 VISTA. In development the system has been integrated by Adacel Systems Inc with the speech recognition module supplied by SRI International.

A helmet mounted display system (HMDS) will be fitted to all models of the F-35. While some fourth-generation fighters (such as the Swedish JAS 39 Gripen) have offered HMDS along with a head up display (HUD), this will be the first time in several decades that a front-line tactical jet fighter has been designed to not carry a HUD.

The pilot flies the aircraft by means of a right-hand side-stick and left-hand throttle.
The Martin-Baker US16E ejection seat is used in all F-35 variants. The US16E seat design balances major performance requirements, including safe terrain clearance limits, pilot load limits, and pilot size. It uses a twin-catapult system that is housed in side-rails.

Sensors
The main sensor on board the F-35 is its AN/APG-81 AESA-radar, designed by Northrop Grumman Electronic Systems. It is augmented by the Electro-Optical Targeting System (EOTS) mounted under the nose of the aircraft, designed by Lockheed Martin. Six additional passive infrared sensors are distributed over the aircraft as part of Northrop Grumman's AN/ASQ-37 distributed aperture system (DAS), which acts as a missile warning system, reports missile launch locations, detects and tracks approaching aircraft spherically around the F-35, and replaces traditional night vision goggles for night operations and navigation. All DAS functions are performed simultaneously, in every direction, at all times. The F-35's Electronic Warfare systems are designed by BAE and include Northrop Grumman components. The communications, navigation and identification (CNI) suite is designed by Northrop Grumman.

Engines
Two different jet engines are being developed for the F-35; the Pratt & Whitney F135 and the General Electric/Rolls-Royce F136. The STOVL versions of both powerplants use the Rolls-Royce LiftSystem, patented by Lockheed Martin and built by Rolls-Royce. This system is more like the Russian Yak-141 and German VJ 101D/E than the preceding generation of STOVL designs, such as the Harrier Jump Jet.

The LiftSystem is composed of a lift fan, driveshaft, clutch, 2 roll posts and a "3 Bearing Swivel Module" (3BSM). The 3BSM is a thrust vectoring nozzle which allows the main engine exhaust to be deflected downward at the tail of the aircraft. The lift fan near the front of the aircraft provides a counter-balancing thrust. Somewhat like a vertically mounted turboprop within the forward fuselage, the lift fan is powered by the engine's low-pressure (LP) turbine via a driveshaft and gearbox. Roll control during slow flight is achieved by diverting pressurized air from the LP turbine through wing mounted thrust nozzles called Roll Posts.

The F-35B lift fan achieves the same 'flow multiplier' effect as the Harrier's huge, but supersonically impractical, main fan. Like lift engines, this added machinery is just deadweight during horizontal flight but provides a net increase in payload capacity during vertical flight. The cool exhaust of the fan also reduces the amount of hot, high-velocity air that is projected downward during vertical takeoff (which can damage runways and aircraft carrier decks). Though complicated and potentially risky, the lift system has been made to work to the satisfaction of DOD officials.

Armament
The F-35 includes a GAU-22/A four-barrel 25 mm cannon. The cannon will be mounted internally with 180 rounds in the F-35A and fitted as an external pod with 220 rounds in the F-35B and F-35C.

Internally (current planned weapons for integration), up to two air-to-air missiles and two air-to-ground weapons (up to two 2,000 lb bombs in A and C models; two 1,000 lb bombs in the B model) in the bomb bays. These could be AIM-120 AMRAAM, AIM-132 ASRAAM, the Joint Direct Attack Munition (JDAM) — up to 2,000 lb (910 kg), the Joint Standoff Weapon (JSOW), Small Diameter Bombs (SDB) — a maximum of four in each bay, the Brimstone anti-armor missiles, and Cluster Munitions (WCMD). The MBDA Meteor air-to-air missile is currently being adapted to fit internally in the missile spots and may be integrated into the F-35. The UK had originally planned to put up to four AIM-132 ASRAAM internally but this has been changed to carry 2 internal and 2 external ASRAAMs. It has also been stated by a Lockheed executive that the internal bay will eventually be modified to accept up to 6 AMRAAMs.

At the expense of being more detectable by radar, many more missiles, bombs and fuel tanks can be attached on four wing pylons and two wingtip positions. The two wingtip pylons can only carry AIM-9X Sidewinders, while the AIM-120 AMRAAM, Storm Shadow, Joint Air to Surface Stand-off Missile (JASSM) cruise missiles and 480 gallon fuel tanks can be carried in addition to the stores already integrated. An air-to-air load of eight AIM-120s and two AIM-9s is conceivable using internal and external weapons stations, as well as a configuration of six two thousand pound bombs, two AIM-120s and two AIM-9s. With its payload capability, the F-35 can carry more air to air and air to ground weapons than legacy fighters it is to replace as well as the F-22 Raptor.

Concerns over performance
Concerns about the F-35's performance have resulted partially from reports of RAND simulations where numerous Russian Sukhoi fighters defeat a handful of F-35s. As a result of these issues the Australian defence minister, Joel Fitzgibbon, requested a formal briefing from the Department of Defence (Australia) on the computer simulation. This briefing stated that the reports of the simulation were inaccurate, and that it did not compare the F-35's performance against that of other aircraft.

The criticism of the F-35 has been dismissed by the Pentagon and manufacturer. The USAF has conducted an analysis of the F-35's air-to-air performance against all 4th generation fighter aircraft currently available, and has found the F-35 to be at least four times more effective. Maj Gen Charles R. Davis, USAF, the F-35 program executive officer, has stated that the "F-35 enjoys a significant Combat Loss Exchange Ratio advantage over the current and future air-to-air threats, to include Sukhois". The Russian, Indian, Chinese, and other air forces operate Sukhoi Su-27/30 fighters.

Manufacturing responsibilities
Lockheed Martin Aeronautics is the prime contractor and performs aircraft final assembly, overall system integration, mission system, and provides forward fuselage, wings and flight controls system. Northrop Grumman provides Active Electronically Scanned Array (AESA) radar, center fuselage, weapons bay, and arrestor gear. BAE Systems provides aft fuselage and empennages, horizontal and vertical tails, crew life support and escape systems, Electronic warfare systems, fuel system, and Flight Control Software (FCS1). Alenia will perform final assembly for Italy and, according to an Alenia executive, assembly of all European aircraft with the exception of Turkey and the UK's.

Operational history
Testing
On 19 February 2006, the first F-35A (designated AA-1) was rolled out in Fort Worth, Texas. The aircraft underwent extensive ground testing at Naval Air Station Fort Worth Joint Reserve Base, adjacent to Lockheed Martin's Fort Worth manufacturing facility, in fall 2006. On 15 September 2006 the first engine run of the F135 afterburning turbofan was conducted in an airframe, with the tests completed on 18 September after a static run with full afterburner. The engine runs were the first time that the F-35 was completely functional on its own power systems. On 15 December 2006, the F-35A completed its maiden flight.

On 3 May 2007, an electrical problem consisting of electrical arcing inside a hydraulic control box forced the aircraft to make an emergency landing. It was grounded until 7 December, when test pilot Jon Beesley flew a 55-minute test flight.

A unique feature of the test program is the use of the so-called Lockheed CATBird avionic testbed, a highly modified Boeing 737-330, inside of which are racks holding all of F-35's avionics, as well as a complete F-35 cockpit.

On 31 January 2008 at Fort Worth, Texas, Lt Col James "Flipper" Kromberg of the U.S. Air Force became the first military service pilot to evaluate the F-35, taking the aircraft through a series of maneuvers on its 26th flight.

On 12 March 2008, the first F-35A (designated AA-1) began aerial refueling testing on its 34th test flight. Another milestone was reached on 13 November 2008, when the AA-1 flew supersonic for the first time. A speed of Mach 1.05 was reached at 30,000 feet (9,144 meters), including four transitions through the sound barrier, and a total of eight minutes in supersonic flight.

On 11 June 2008, after extensive ground testing, the first F-35B (designated BF-1) made its maiden flight at Fort Worth. The flight, which featured a conventional takeoff, was piloted by BAE Systems' test pilot Graham Tomlinson. The BF-1 is the second of 19 System Development and Demonstration (SDD) F-35s, and the first to use new weight-optimized design features that will apply to all future F-35s.

On 19 December 2008, Lockheed Martin rolled out the first weight-optimized F-35A (designated AF-1). It is the first F-35 to be produced at a full-rate production speed — the assembly line moves at 50 inches (127 centimeters) per hour — and is structurally identical to final production F-35As that will be delivered starting in 2010.

As of 5 January 2009, six F-35s are complete, including AF-1 and AG-1, and 17 are in production. "Thirteen of the 17 in production are pre-production test aircraft, and all of those will be finished in 2009," said John R. Kent, acting manager of F-35 Lightning II Communications at Lockheed Martin Aeronautics Company. "The other four are the first production-model planes, and the first of those will be delivered in 2010 to the U.S. Air Force, and will go to Eglin."

Environmental concerns
In late 2008 the Air Force revealed that the F-35 would be about twice as loud at takeoff as the F-15 Eagle and up to four times as loud upon landing. As a result, residents near Davis-Monthan Air Force Base, Arizona and Eglin Air Force Base, Florida, possible homes of the jet, have requested that the Air Force conduct environmental impact studies concerning the F-35's noise levels. The city of Valparaiso, Florida, adjacent to Eglin AFB threatened in February 2009 to sue the Air Force over the impending arrival of the F-35s.

International participation
While the United States is the primary customer and financial backer, the United Kingdom, Italy, the Netherlands, Canada, Turkey, Australia, Norway and Denmark have agreed to contribute US$4.375 billion toward the development costs of the program. Total development costs are estimated at more than US$40 billion (underwritten largely by the United States), while the purchase of an estimated 2,400 planes is expected to cost an additional US$200 billion. The nine major partner nations plan to acquire over 3,100 F-35s through 2035, making the F-35 one of the most numerous jet fighters.

There are three levels of international participation. The levels generally reflect the financial stake in the program, the amount of technology transfer and subcontracts open for bid by national companies, and the order in which countries can obtain production aircraft. The United Kingdom is the sole "Level 1" partner, contributing US$2.5 billion, about 10% of the development costs under the 1995 Memorandum of Understanding that brought the UK into the project. Level 2 partners are Italy, which is contributing US$1 billion; and the Netherlands, US$800 million. Level 3 partners are Canada, US$475 million; Turkey, US$195 million; Australia, US$144 million; Norway, US$122 million and Denmark, US$110 million. Israel and Singapore have joined as Security Cooperative Participants (SCP).

Some of the partner countries have wavered in their public commitment to the JSF program, hinting or warning that unless they receive more subcontracts or technology transfer, they will forsake JSF for the Eurofighter Typhoon, Saab JAS 39 Gripen, Dassault Rafale or simply upgrade their existing aircraft. Norway has several times threatened to put their support on hold unless substantial guarantees for an increased industrial share is provided. Despite this Norway has signed all the Memoranda of Understanding, including the latest one detailing the future production phase of the JSF program. They have, however, indicated that they will increase and strengthen their cooperation with both competitors of the JSF, the Typhoon and the Gripen.

United Kingdom
Main article: Joint Combat Aircraft
The United Kingdom planned to acquire 138 F-35Bs as of December 2006 for the Royal Air Force and the Royal Navy.
The UK became increasingly frustrated by a lack of U.S. commitment to grant access to the technology that would allow the UK to maintain and upgrade its F-35s without US involvement. This is understood to relate mainly to the software for the aircraft. For five years, British officials sought an ITAR waiver to secure greater technology transfer. This request, which had the blessing of the Bush administration, was repeatedly blocked by U.S. Representative Henry Hyde, who said that the UK needed to tighten its laws protecting against the unauthorized transfer of the most advanced U.S. technology to third parties.

On 27 May 2006, President George W. Bush and Prime Minister Tony Blair announced that "Both governments agree that the UK will have the ability to successfully operate, upgrade, employ, and maintain the Joint Strike Fighter such that the UK retains operational sovereignty over the aircraft." On 12 December 2006, Lord Drayson signed an agreement which met the UK's demands for further participation, i.e., access to software source code and operational sovereignty. The agreement allows "an unbroken British chain of command" for operation of the aircraft. Drayson said Britain would "not be required to have a US citizen in our own operational chain of command". Drayson also said, however, that Britain is still considering an unspecified "Plan B" alternative to buying the Joint Strike Fighter.

On 25 July 2007, the Ministry of Defence confirmed that they have placed orders for the two new aircraft carriers of the Queen Elizabeth class that will allow the purchase of the F-35B variant. On 2 May 2008, however, the Washington Post reported that an Inspector General's report chided the U.S. Department of Defense's Defense Security Service for failing to ensure that BAE Systems was exercising appropriate controls over access to sensitive technologies, while both BAE and Lockheed Martin denied that any technology had been compromised.

On 18 March 2009, Defence Secretary John Hutton announced the MoD had agreed to purchase three test F-35s.

Italy
As of October 2008, Italy planned to acquire 131 of the planes: 109 F-35As and 22 F-35Bs. On 7 October 2008, Italy announced it will not participate in initial F-35 testing and evaluation, and will not purchase test aircraft. The Navy plans to use the F-35Bs on their new Cavour STOVL Carrier.

Netherlands
The Netherlands has plans to acquire 85 F-35As for the Royal Netherlands Air Force. The aircraft will replace an aging fleet of Lockheed Martin F-16AM. The Dutch government expects the costs to be €5.5 billion for the initial purchase and €9.1 billion for 30 years of service. On 19 November 2007, in the Dutch Parliament, the Secretary of Defence was questioned about the JSF delay, technical problems and rising costs. However, on 29 February 2008, the executive council of the Dutch government decided to go ahead with the purchase of two test aircraft and a MOU was signed. On 7 September 2008 Dutch television show "Reporter" reports that counter orders are lagging behind compared to promises and that an active lobby by the Royal Netherlands Air Force has manipulated the Dutch government into participating in the project.

Canada
Canada has been involved in the Joint Strike Fighter Program from its beginning, investing US$10 million to be an "informed partner" during the evaluation process. Once Lockheed Martin was selected as the primary contractor for the JSF program, Canada elected to become a level 3 participant along with Norway, Denmark, Turkey, and Australia on the JSF project. An additional US$100 million from the Canadian Department of National Defence (DND) over 10 years and an another $50 million dollars from Industry Canada was dedicated in 2002 making them an early participant of the JSF program.

Canada's rationale for joining the JSF project was not due to an urgent need to replace Canada's fleet of CF-18 Hornets; instead it was driven primarily by economics. Through Canadian government investment in the JSF project, Canadian companies were allowed to compete for contracts within the JSF project, as there were fears that being shut out from industrial participation in such a large program would severely damage the Canadian aviation industry. Joining furthered Canadian access to information regarding the F-35 as a possible contender when it eventually plans to replace the CF-18 Hornet fleet. Improved interoperability with major allies, allowed the DND to gain insight on leading edge practices in composites, manufacturing and logistics, and the ability to recoup some investment if the government did decide to purchase the F-35.

As a result of the Canadian government investment in the JSF project, 144 contracts were awarded to Canadian companies, universities, and government facilities. Financially the contracts value US$490 million for the period 2002 to 2012, with an expected value of US$1.1 billion from current contracts in the period between 2013 and 2023, and a total potential estimated value of Canadian JSF involvement from US$4.8 billion to US$6.8 billion.

Turkey
On 12 July 2002, Turkey became the seventh international partner in the JSF Project, joining the United Kingdom, Italy, the Netherlands, Canada, Denmark and Norway. On 25 January 2007, Turkey signed a memorandum of understanding (MoU) for involvement in F-35 production. The Turkish Air Force is planning to initially order 116 F-35A "CTOL/Air Force versions" at a reported cost of $11 billion. It is reported that the aircraft will be produced under license in Turkey by the Turkish Aerospace Industries (TAI).

A Letter of Intent (LOI) was signed between TAI and Northrop Grumman ISS (NGISS) International on 6 February 2007. With the LOI, TAI becomes the second source for the F-35 Lightning II center fuselage during the JSF Signing. The number of center fuselages to be produced by Turkish Aerospace Industries will be determined depending on the number of F-35s Turkey will procure and the number of F-35s to be produced worldwide. The LOI represents a potential value in excess of $3 billion. Northrop Grumman currently produces all F-35 center fuselages at its F-35 assembly facility in Palmdale, California.

TAI of Turkey is one of the two international suppliers to Northrop Grumman (the other being Denmark). On 10 December 2007, the Turkish Aerospace Industries, Inc. (TAI) was authorized by the Northrop Grumman to commence fabricating subassemblies for the first two F-35 production aircraft. The subassemblies – composite components and aircraft access doors – will be used in the F-35 center fuselage, a major section of the aircraft being produced by Northrop Grumman, a principal member of the Lockheed Martin-led F-35 global industry team.

It is also anticipated that TAI after 2013 will also produce 100% of the F-35 under license from Lockheed Martin Corporation, as was also the case with the F-16 Fighting Falcon program Peace Onyx I and II. Turkey also intends to incorporate in the future several Turkish designed and manufactured electronic systems into the F-35 platform.

Australia
Australia is participating in the F-35's development, but has not yet placed an order for the aircraft. It is expected that some 75 to 100 F-35As will be ordered to replace the Royal Australian Air Force's (RAAF's) F/A-18 Hornet aircraft.

The Australian Government announced that it would buy into the F-35's development on 22 June 2002. This decision ended the competition to replace Australia's F/A-18 and F-111 aircraft before it formally began, with other aircraft manufacturers being advised that it would not be worth submitting proposals. The Government argued that joining the F-35 program at an early stage would allow Australia to influence the F-35's development, provide the Government with information on the aircraft's suitability, and generate savings of over $600 million if an order for F-35s is eventually placed. Australia formally signed up to the F-35 Systems Development and Demonstration phase as a Level 3 participant on 30 October 2002.

In November 2006, satisfied with the F-35's progress to date, the Government gave 'first pass' initial approval to the project under which F-35s will be acquired, with a decision on whether to order the aircraft being scheduled for late 2008. Following this initial approval, on 13 December 2006 Australia signed the JSF Production, Sustainment and Follow-on Development Memorandum of Understanding which commits Australia to the next phase of the F-35's development. In October 2006, the deputy chief of the Air Force, Air Vice Marshal John Blackburn, publicly stated that the RAAF had considered suitable aircraft which could be acquired if the F-35 was delayed, but that such aircraft were not believed to be necessary on the basis of the F-35 program's progress at the time.

Concerns over the F-35s delivery schedule developed in Australia during 2007. In February the Minister for Defence announced that a risk mitigation strategy which involved obtaining F/A-18F Hornets was being developed to prevent a gap in the RAAF's air combat capability if the F-35 program was delayed. This strategy was adopted, and an order for 24 F/A-18Fs was announced on 6 March 2007. These aircraft are scheduled to enter service with the RAAF in 2010 and be fully operational by 2012.

Following the 2007 Australian Federal Election, the new Australian Labor Party Government launched an inquiry into the replacement of the RAAF's air combat capability. The party had expressed concerns over the F-35's adequacy while it was in opposition, and proposed acquiring F-22s to replace or supplement the RAAF's F-35 force. An approach was made to the U.S. Government for F-22s in early 2008, but was not successful as these aircraft are not available for export. In April 2008 it was reported that the air combat review had found that the F-35 was the most suitable aircraft for Australia. In October 2008 it was reported that the Australian Government may order 75 F-35s instead of the 100 originally (and still officially) planned, due to the impact of the global financial crisis and a large long-term funding gap in the Defence budget. However, in April 2009, the Government released a white paper confirming an intended purchase of 100 F-35s.

There has been debate in Australia over whether the F-35 is the most suitable aircraft for the RAAF. It has been claimed that the F-35's performance is inferior to Russian-built aircraft operated by countries in Australia's region, that the F-35 cannot meet the RAAF's long-range strike requirement, and that delays to the F-35 program will result in the RAAF experiencing a shortage of combat aircraft. The RAAF believes that the F-35 will meet Australia's needs, however, and both of Australia's major political parties currently support purchasing the aircraft, though they differ over when the order should be placed.

Norway
Norway participates in the F-35 program as a Level 3 partner in the System Development and Demonstration phase with a view to enabling its industry to compete for industrial opportunities. Norwegian National Deputy Rune Fagerli, the country's sole representative on the Joint Strike Fighter program, told SPACE.com the Norwegian Royal Ministry of Defence has pledged $125 million in preparations to replace a fleet of F-16 jets that have about 12 years left of operation. "By getting involved here, on the ground level, we can try and address the needs of Norway into this capable fighter early," said Fagerli, a colonel. In Norway, F-16s are fitted with drag chutes because of wet, slippery runways. International cooperation to aircraft development could also yield aircraft from cooperating nations that fit well together during combat. Fagerli also mentioned that Norwegian pilots currently fly missions over Afghanistan in F-16s alongside Danish and Dutch aviators.

The F-35 was evaluated along with JAS 39 Gripen by the Norwegian Future Combat Aircraft Capability Project as a replacement for the F-16s currently in-service. On 20 November 2008, the government released a statement saying it will support buying F-35s for the Royal Norwegian Air Force instead of the Saab Gripen NG.

Denmark
Denmark has joined the Joint Strike Fighter program as a Level 3 partner and the Royal Danish Air Force is considering the replacement of 48 of its aging F-16 fighters with next generation aircraft.

Security Cooperative Participants (SCP)
Israel
In 2003, Israel signed a formal letter of agreement, worth almost $20 million, to join the System Development and Demonstration (SDD) effort for the F-35 as a "security cooperation participant" (SCP). The Israeli Air Force (IAF) stated in 2006 that the F-35 is a key part of IAF's recapitalization plans, and that Israel intends to buy over 100 F-35A fighters at an estimated cost of over $5 billion to replace their F-16s over time. Israel was reinstated as a partner in the development of the F-35 on 31 July 2006, after Israeli participation was put on hold following the Chinese arms deal crisis.

On 3 September 2007, IDF Chief of General Staff Lt.-Gen. Gabi Ashkenazi announced the purchase of a squadron of F-35s which Israel will begin receiving in 2014. However, U.S. defense officials later agreed to allow Israel to receive the fighters as early as 2012. The price of each F-35 is expected to reach $70–80 million.

The Jerusalem Post reports the Pentagon has agreed to supply the F-35A variant to Israel as early as 2012, instead of in 2014 or 2015. This would make Israel one of the first nations to receive the aircraft, and very possibly the first foreign nation. Previous objections to Israel’s installation of its own technology in the F-35 — as it has done with every US fighter it has received — were also reportedly overcome. At present, the only Israeli technology in the standard version will be the JSF HMDS helmet-mounted display system, designed in cooperation with Elbit Systems. Israel also asked to manufacture F-35 aircraft locally at a 1:2 ratio, but the reports did not indicate whether that request was granted. On 30 September 2008, the US DoD reported that Israel has requested to purchase 25 F-35As with options to buy up to 50 F-35As or F-35Bs.

Singapore
In February 2003, Singapore joined the JSF program's System Design and Development (SDD) Phase, as a Security Co-operation Participant (SCP).

Potential exports
The F-35 is a possible future offer to the Indian Air Force as of July 2007. This has been interpreted as part of a tactic to sell the F-16 as a multirole fighter to the IAF, as part of its competition to acquire 126 new fighters. Lockheed Martin formally expressed its interest to sell F-35 to India. It is also known that the Indian Navy has shown interest in buying the F-35B.

The Brazilian Air Force recently has added the F-35 Joint Strike Fighter to the list of aircraft under consideration for its relaunched new fighter procurement, called F-X2. The F-35 replaces the F-16, which was in contention for the previous F-X BR program, shelved in 2003 and finally abandoned in 2006. Lockheed Martin did not offer the F-35 and instead bid the F-16BR in 2008.
The Finnish Air Force has expressed its interest in the F-35, and other "advanced aircraft", as the replacement for its F-18C Hornets. An eventual purchase decision would be taken around 2015.

The future Spanish Navy ship Juan Carlos I (L61) is adapted to carry JSF and AV-8B Harrier.
Lockheed Martin is offering the F-35 to the Hellenic Air Force as F-4E Peace Icarus 2000 and F-16C/D Block 30 replacement.

The Republic of China (Taiwan) has requested to buy the F-35 from the US. However this has been rejected by the US in fear of a critical response from Beijing. In March 2009 Taiwan again was looking to buy U.S. fifth-generation fighter jets featuring stealth and vertical takeoff capabilities.

Variants
The F-35 is planned to be built in three different versions to suit the needs of its various users. Secretary Gates proposed speeding up production of the F-35 fighter jet, which could end up costing $1 trillion to manufacture and maintain 2,443 planes.

F-35A
The F-35A is the conventional takeoff and landing (CTOL) variant intended for the US Air Force and other air forces. It is the smallest, lightest F-35 version and is the only variant equipped with an internal cannon, the GAU-22/A. This 25 mm cannon is a development of the GAU-12 carried by the USMC's AV-8B Harrier II. It is designed for increased effectiveness compared to the 20 mm M61 Vulcan cannon carried by other USAF fighters.

The F-35A is expected to match the F-16 in maneuverability, instantaneous and sustained high-g performance, and outperform it in stealth, payload, range on internal fuel, avionics, operational effectiveness, supportability and survivability It also has an internal laser designator and infrared sensors.

The A variant is primarily intended to replace the USAF's F-16 Fighting Falcon, beginning in 2013, and replace the A-10 Thunderbolt II starting in 2028.

F-35B
The F-35B is the short takeoff and vertical landing (STOVL) variant of the aircraft. Similar in size to the A variant, the B sacrifices some fuel volume to make room for the vertical flight system. Takeoffs and landing with vertical flight system are by far the riskiest, and in the end, a decisive factor in design. Like the AV-8B Harrier II, the B's guns will be carried in a ventral pod. Whereas F-35A is stressed to 9 g, F-35B and F-35C are stressed to 7.5 g.

The British Royal Air Force and Royal Navy plan to use this variant to replace their Harrier GR7/GR9s. The United States Marine Corps intends to purchase 340 F-35Bs to replace all current inventories of the F/A-18 Hornet, AV-8B Harrier II and possibly the EA-6B Prowler in the fighter, attack, and electronic warfare roles.

The F-35B was unveiled at Lockheed's Fort Worth plant on 18 December 2007, and the first test flight was on 11 June 2008. The B variant is expected to be available beginning in 2012.

F-35C
The F-35C carrier variant will have a larger, folding wing and larger control surfaces for improved low-speed control, and stronger landing gear for the stresses of carrier landings. The larger wing area allows for decreased landing speed, increased range and payload, with twice the range on internal fuel compared with the F/A-18C Hornet, achieving much the same goal as the heavier F/A-18E/F Super Hornet.

The United States Navy will be the sole user for the carrier variant. It intends to buy 480 F-35Cs to replace the F/A-18A, -B, -C, and -D Hornets. The F-35C will also serve as a stealthier complement to the Super Hornet. On 27 June 2007, the carrier variant completed its Air System Critical Design Review (CDR). This allows the first two functional prototype F-35C units to be produced. The C variant is expected to be available beginning in 2015.

Specifications (F-35 Lightning II)
Crew: 1
Length: A: 51.4 ft, B: 51.3 ft, C: 51.5 ft (A: 15.67 m, B: 15.6 m, C: 15.7 m)
Wingspan: A/B: 35 ft, C: 43 ft (A/B: 10.7 m, C: 13.1 m)
Height: A/B: 14.2 ft, C: 14.9 ft (A/B: 4.33 m, C: 4.54 m)
Wing area: A/B: 460 ft², C: 668 ft² (A/B: 42.7 m², C: 62.1 m²)
Empty weight: A: 29,300 lb, B: 32,000 lb, C: 34,800 lb (A: 13,300 kg, B: 14,500 kg, C: 15,800 kg)
Loaded weight: 44,400 lb (20,100 kg)
Max takeoff weight: A/C: 70,000 lb, B: 60,000 lb (A/C: 31,800 kg, B: 27,200 kg)
Powerplant: 1× Pratt & Whitney F135 afterburning turbofan
Dry thrust: 25,000 lbf (111 kN)
Thrust with afterburner: 40,000+ lbf (178+ kN)
Secondary Powerplant: 1× General Electric/Rolls-Royce F136 afterburning turbofan, >40,000 lbf (178 kN) [in development]
Lift fan (STOVL): 1× Rolls-Royce LiftSystem driven from either F135 or F136 power plant, 18,000 lbf (80 kN)
Internal fuel: F-35A: 18,480 lb (8,382 kg); F-35B: 14,003 lb (6,352 kg); F-35C: 20,085 lb (9,110 kg)

Performance
Maximum speed: Mach 1.6+ (1,200 mph, 1,931 km/h)
Range: A: 1,200 nmi; B: 900 nmi; C: 1,400 nmi (A: 2,220 km; B: 1,670 km; C: 2,520 km) on internal fuel
Combat radius: A: 610 nmi; B: 500 nmi; C: 640 nmi (A: 1,110 km; B: 910 km; C: 1,150 km) on internal fuel
Service ceiling: A/B/C: 60,000 ft (18,288 m)
Rate of climb: classified (not publicly available)
Wing loading: 91.4 lb/ft² (446 kg/m²)
Thrust/weight:
With full fuel: A: 0.89; B: 0.92; C: 0.81
With 50% fuel: A: 1.12; B: 1.10; C: 1.01
g-Limits: F-35A: 9 g, F-35B: 7.5 g, F-35C: 7.5 g

Armament
Guns: 1 × GAU-22/A 25 mm (0.984 in) cannon — slated to be mounted internally with 180 rounds in the F-35A and fitted as an external pod with 220 rounds in the F-35B and F-35C.
Hardpoints: 6× external pylons on wings with a capacity of 15,000 lb (6,800 kg) and 2× internal bays with 2 pylons each,
Missiles:
Internal: 4 air-to-air missiles, or 2 air-to-air missiles and 2 air-to-ground weapons.
External: 6 air-to-air missiles, or 4 air-to-ground weapons and 2 air-to-air missiles with combinations for the following missiles:
Air-to-air missiles:
AIM-120 AMRAAM
AIM-132 ASRAAM
AIM-9X Sidewinder
Air-to-ground weapons:
AGM-154 JSOW
AGM-158 JASSM
Bombs:
Mark 84 general purpose bombs
Mark 83 GP bombs
Mark 82 GP bombs
Mk.20 Rockeye II cluster bomb
Wind Corrected Munitions Dispenser capable
Paveway-series laser-guided bombs
JDAM-series

 

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F-22 Raptor



The Lockheed Martin/Boeing F-22 Raptor is a fifth-generation, fighter aircraft that uses stealth technology. It is primarily an air superiority fighter, but has multiple capabilities that include ground attack, electronic warfare, and signals intelligence roles.

The United States Air Force considers the F-22 a critical component of the US strike force, and claims that the F-22 cannot be matched by any known or projected fighter aircraft. Air Chief Marshal Angus Houston, Chief of the Australian Defence Force, said in 2004 that the "F-22 will be the most outstanding fighter plane ever built."

Faced with a protracted and costly development period, the aircraft was variously designated F-22 and F/A-22 during the three years before formally entering US Air Force service in December 2005, as the F-22A. Lockheed Martin Aeronautics is the prime contractor and is responsible for the majority of the airframe, weapon systems and final assembly of the F-22. Program partner Boeing Integrated Defense Systems provides the wings, aft fuselage, avionics integration, and all of the pilot and maintenance training systems.

Development

In 1981 the United States Air Force (USAF) developed a requirement for a new air superiority fighter, the Advanced Tactical Fighter (ATF), to replace the capability of the F-15 Eagle, primarily the F-15A, B, C and D variants. ATF was a demonstration and validation program undertaken by the USAF to develop a next-generation air superiority fighter to counter emerging worldwide threats, including development and proliferation of Soviet-era Su-27 "Flanker"-class fighter aircraft. It was envisaged that the ATF would incorporate emerging technologies including advanced alloys and composite materials, advanced fly-by-wire flight control systems, higher power propulsion systems, and low-observable/stealth technology.

A request for proposal (RFP) was issued in July 1986, and two contractor teams, Lockheed/Boeing/General Dynamics and Northrop/McDonnell Douglas were selected in October 1986 to undertake a 50-month demonstration/validation phase, culminating in the flight test of two prototypes, the YF-22 and the YF-23.

On 23 April 1991 the USAF ended the design and test flight competition by announcing Lockheed's YF-22 as the winner. It was anticipated at the time that 650 aircraft would be ordered.

Into production

The first operational F-22 Raptor is painted at the Lockheed Martin assembly plant at Marietta, Georgia

The first production F-22 was delivered to Nellis Air Force Base, Nevada, on 14 January 2003 and "Dedicated Initial Operational Test and Evaluation" commenced on 27 October 2003. By 2004, 51 Raptors had been delivered.

The first crash of a production F-22 occurred during takeoff at Nellis Air Force Base on 20 December 2004, in which the pilot ejected safely prior to impact. The crash investigation revealed that a brief interruption in power during an engine shutdown prior to flight caused a malfunction in the flight-control system; consequently, the aircraft design was corrected to avoid the problem.

In August 2007, the United States Air Force signed a $5 billion, multi-year contract with Lockheed Martin that will extend production to 2011, and as of 2008, F-22 Raptors are being procured at the rate of 20

per year.

In a ceremony on 29 August 2007, Lockheed Martin reached its "100th F-22 Raptor" milestone, delivering AF Serial No. 05-4100.

Procurement

Two F-22s during flight testing, the upper one being the first EMD F-22, "Raptor 01".

The United States Air Force originally planned to order 750 ATFs, with production beginning in 1994; however, the 1990 Major Aircraft Review altered the plan to 648 aircraft beginning in 1996. The goal changed again in 1994, when it became 442 aircraft entering service in 2003 or 2004, but a 1997 Department of Defense report put the purchase at 339. In 2003, the Air Force said that the existing congress

ional cost cap limite

d the purchase to 277. By 2006, the Pentagon said it will buy 183 aircraft, which would save $15 billion but raise the cost of each aircraft, and this plan has been de facto approved by Congress in the form of a multi-year procurement plan, which still holds open the

possibility for new orders past that point. The total cost of the program by 2006 was $62 billion.

In April 2006, the cost of the F-22 was assessed by the Government Accountability Office to be $361 milli

on per aircraft. This cost reflects the F-22 total program cost, divided by the number of fighters the Air Force is programmed to buy; and which has so far invested $28 billion in the Raptor's research, development and testing. That money, referred to as a "sunk cost", is already spent and is separate from money used for future decision-making, including procuring a copy of the jet. The Unit Procurement Cost was estimated at $177.6 million in 2006 based on a production run of 181 airframes. This unit cost will decrease if total production is higher. This cost includes $3.233 billion already spent on research and development by 2006.

By the time all 183 fighters have

been purchased, $34 billion will have been spent on actual procurement, resulting in a total program cost of $62 billion or about $339 million per aircraft. The incremental cost for one additional F-22 i

s around $138 million;decreasing with larger volumes. If the Air Force were to buy 100 more F-22s today, the cost of each one would be less and would continue to drop with additional aircraft purchases.

F-22 Raptors over Utah in their

first official deployment, October 2005.

The F-22 is not the most expensive aircraft aloft. That distinction likely belongs to the roughly $2.2 billion-per-unit B-2 Spirit, whose orders went from 132 to 21 when the

Cold War ended thus making the unit cost skyrocket, th

ough the incremental cost was under US$1 billion. The F-22 uses fewer radar absorbent materials than the B-2 or F-117 Nighthawk, which is expected to translate into lower maintenance costs.

On 31 July 2007, Lockheed Martin received a multiyear

contract for 60 F-22s worth a total of US$7.3 billion. The contract b

rings the number of F-22s on order to 183 and extends production through 2011.

During the two-month grounding of nearly 700 older F-15s in November and December 2007, some US Senators demanded that Deputy Secretary of Defense Gordon England release three government reports that support additional F-22 Raptors beyond the planned 183 jets.The USAF has requested that the F-22 remain in produc

tion after the 183 planned fighters. This is believed to be a response to the recent grounding of F-15A-D fighters.

In January 2008, the Pentagon announced that

it would ask Congress for funds to buy additional F-22s to replace other aircraft lost in combat, and proposed that $497 million that would have been used to shut down the F-22 line instead be used to buy four more F-22s, keeping open the production line beyond 2011 and providing the next Presidential administration the option to buy even more F-22s. The funds earmarked for the line shutdown, however, were directed by Pentagon Comptroller Tina W. Jonas on 17

December 2007, to be used to fund repairs to the F-15 fleet caused by the worldwide grounding of that aircraft in November 2007. This diversion had the same effect of postponing the decision to shut down the F-22 production line until at least 2009.On September 24, 2008, US Congress passed a defense spending bill with funding for F-22 long lead items for future production. On November 12, 2008, the Pentagon released $50 million of the $140 million approved by Congress to buy parts for an additional four planes, thus leaving the Raptor program in the hands of the incoming Obama Administration. Additional funds to complete the four planes will be provided in a future war supplemental bill, which would bring the total planes procured to 187.

Ban on exports

The opportunity for export is currently non-existent because the export sale of the F-22 is barred by American federal law. Most current customers for U.S. fighters are either acquiring earlier designs like the F-15

or F-16, or else are waiting to acquire the F-35, which contains technology from the F-22 but is designed to be cheaper and more flexible. Independent writers have suggested that F-22 may not be offered for export in order not to damage the lucrative F-35 export program.

The Japanese government reportedly showed some interest in buying F-22s in its Replacement-Fighter program for the Japan Air Self-Defense Force (JASDF). If it were to occur, it would most likely involve a "watered-down" export variant while still retaining most of its advanced avionics and stealth

characteristics. However, such a proposal would still need approval from the Pentagon, State Department and Congress.

Israeli Air Force (IAF) chief procurement officer Brigadier-General Ze'ev Snir said that, "The IAF would be happy to equip itself with 24 F-22s, but the problem at this

time is the US refusal to sell the aircraft, and its $200 million price tag."

Some Australian politicians and defense commentators have proposed that Australia purchase F-22s instead of the F-35. In 2006, the Australian Labor Party supported this proposal on the grounds that the F-22 is a proven, highly capable aircraft, while the F-35 is still under development. However, the Howard government ruled out purchase of the F-22, on the grounds

that it is unlikely to be released for export, and does not have sufficient ground/maritime strike capacity. This assessment was supported by the Australian Strategic Policy Institute, which claimed that the F-22 "has i

nsufficient multi-role capability at too high a price. The ASPI analysis was, however, criticized by Air Power Australia.

The US Congress upheld the ban on F-22 Raptor foreign sales during a joint conference on 27 September 2006. After talks in Washington in December 2006, the US DoD reported the F-22 would not be available for foreign sale.

In 2007, the Australian government ordered a review of plans to procure the F-35 and F/A-18E/F Super Hornet. This review will include an evaluation of the F-22's suitability for Australia; moreover, Defe

nce Minister Joel Fitzgibbon has stated: "I intend to pursue American politicians for access to the Raptor". In February 2008, U.S. Defense Secretary Robert Gates said he had no objection to sale of the Raptor to Australia, but Congress would have to change the law.

Design

Characteristics


F-22 Raptor displaying its F119-PW-100 engines on full afterburner during flight testing.

The F-22 is a fifth generation fighter that is considered a fourth-generation stealth aircraft by the USAF. Its dual

afterburning Pratt & Whitney F119-PW-100 turbofans
incorporate pitch axis thrust vectoring, with a r

ange of ±20 degrees. The maximum thrust is classified, though most sources place it at about 35,000 lbf (156 kN) per engine. Maximum speed, without external weapons, is estimated to be Mach 1.82 in supercruise mode; as demonstrated by Genera

l John P. Jumper, former US Air Force Chief of Staff, when his Raptor exceeded Mach 1.7 without afterburners on 13 January 2005. With afterburners, it is "greater than Mach 2.0" (1,317 mph, 2,120 km/h), according to Lockheed Martin; however, the Raptor can easily exceed its design speed limits, particularly at low altitudes, with max-speed alerts to help prevent the pilot from exceeding them. Former Lockheed Raptor chief test pilot Paul Metz stated that the Raptor has a fixed inlet; but while the absence of variable intake ramps may theoretically make speeds greater than Mach 2.0 unreachable, there is no evidence to prove this. Such ramps would be used to prevent engine surge resulting in a compressor stall, but the intake itself may be designed to prevent this. Metz has also stated that the F-22 has a top speed greater than 1,600 mph (Mach 2.42) and its climb rate is faster than the F-15 Eagle due to advances in engine technology, despite the F-15's thrust-to-weight ratio of about 1.2:1, with the F-22 having a ratio close

r to 1:1. The US Air Force claims that the F-22A cannot be matched by any known or projected fighter.



A KC-10 Extender (top) refuels an F-22 Raptor.

The true top-speed of the F-22 is unknown to the general public. The ability of the airframe to withstand the stress and heat from friction is a further key factor, especially in an aircraft using as many polymers as the F-22. However, while some aircraft are faster on paper, the internal carriage of its standard combat load allows the aircraft to reach comparatively higher performance with a heavy load over other modern aircraft due to its lack of drag from external stores. It is one of only a handful of aircraft that can sustain supersonic flight without the use of afterburner augmented thrust (and its associated high fuel usage). This ability is called supercruise.

The F-22 is highly maneuverable, at both supersonic and subsonic speeds. It is extremely departure-resistant, enabling it to remain controllable at extreme pilot inputs. The F-22's thrust vectoring nozzles allow the aircraft to turn tightly, and perform extremely high alpha (angle of attack) maneuvers such as the Herbst maneuver (or J-turn), Pugachev's Cobra, and the Kulbit, though the J-Turn is more useful in combat. The F-22 is also capable of maintaining a constant angle of attack of over 60°, yet still having some control of roll. During June 2006 exercises in Alaska, F-22 pilots demonstrated that cruise altitude has a significant effect on combat performance, and routinely attributed their altitude advantage as a major factor in achieving an unblemished kill ratio against other US fighters and 4th/4.5th generation fighters.

Avionics

The F-22's avionics include BAE Systems E&IS radar warning receiver (RWR) AN/ALR-94, AN/AAR 56 Infra-Red and Ultra-Violet MAWS (Missile Approach Warning System) and the Northrop Grumman AN/APG-77 Active Electronically Scanned Array (AESA) radar. The AN/APG-77 has both long-range target acquisition and low probability of interception of its own signals by enemy aircraft.

The AN/ALR-94 is a passive receiver system capable of detecting the radar signals in the environment. Composed of more than 30 antennas smoothly blended into the wings and fuselage, it is described by the former head of the F-22 program at Lockheed Martin Tom Burbage as "the most technically complex piece of equipment on the aircraft." With greater range (250+ NMI) than the radar, it enables the F-22 to limit its own radar emission which might otherwise compromise its stealth. As the target approaches, AN/ALR-94 can cue the AN/APG-77 radar to keep track of its motion with a narrow beam, which can be as focused as 2° by 2° in azimuth and elevation.

The AN/APG-77 AESA radar, designed for air-superiority and strike operations, features a low-observable, active-aperture, electronically-scanned array that can track multiple targets in all kinds of weather. The AN/APG-77 changes frequencies more than 1,000 times per second to reduce the chance of being intercepted. The radar can also focus its emissions to overload enemy sensors, giving the aircraft an electronic-attack capability.

The radar’s information is processed by two Raytheon Common Integrated Processor (CIP)s. Each CIP operates at 10.5 billion instructions per second and has 300 megabytes of memory. Information can be gathered from the radar and other onboard and offboard systems, filtered by the CIP, and offered in easy-to-digest ways on several cockpit displays, enabling the pilot to remain on top of complicated situations. The Raptor’s software is composed of over 1.7 million lines of code, most of which concerns processing data from the radar. The radar has an estimated range of 125-150 miles, though planned upgrades will allow a range of 250 miles (400 km) or more in narrow beams.

The F-22 has several unique functions for an aircraft of its size and role. For instance, it has threat detection and identification capability along the lines of that available on the RC-135 Rivet Joint. While the F-22's equipment isn't as powerful or sophisticated, because of its stealth, it can be typically hundreds of miles closer to the battlefield, which often compensates for the reduced capability.

The F-22 is capable of functioning as a "mini-AWACS." Though reduced in capability compared to dedicated airframes such as the E-3 Sentry, as with its threat identification capability, the F-22's forward presence is often of benefit. The system allows the F-22 to designate targets for cooperating F-15s and F-16s, and even determine if two friendly aircraft are targeting the same enemy aircraft, thus enabling one of them to choose a different target. It is often able to identify targets "sometimes many times quicker than the AWACS."

The F-22's lo

w probability of intercept radar is being given a high-bandwidth data transmission capability, to allow it to be used in a "broadband" role to permit high-speed relaying of data between friendly transmitters and receivers in the area. The F-22 can already pass data to other F-22s, resulting in considerably reduced radio "chatter".

The IEEE-1394B data bus, developed for the F-22, was derived from the commercial IEEE-1394 "FireWire" bus system, often used on personal computers. The same data bus is employed by the subsequent F-35 Lightning II fighter.

Cockpit



Cockpit of the F-22, showing instruments and heads up display.

The F-22 cockpit is a glass cockpit design without any traditional analog flight instruments and represents a marked improvement on the cockpit design of previous advanced aircraft. The leading features of the F-22 cockpit include simple and rapid start-up, highly deve

loped HMI, light helmet, large anthropometric accommodation and highly integrated warning system. Other main features include the large single-piece canopy and improved life support systems.

Airframe

Several small design changes were made from the YF-22A prototype to the production F-22A. The swept-back angle on the wing's leading edge was decreased from 48 degrees to 42 degrees, while the vertical stabilizer area was decreased 20%. To improve pilot visibility, the canopy was moved forward 7 inches (178 mm) and the engine intakes were moved rearward 14 inches (356 mm). The shape of the wing and stabilator trailing edges was refined to improve aerodynamics, strength, and stealth characteristics. The Airframe also features three internal weapons bays on the bottom and sides of the fuselage.

Armament

An F-22 fires an AIM-120 AMRAAM.

The Raptor is designed to carry air-to-air missiles in internal weapons bays, both to avoid disrupting its stealth capability and to reduce drag resulting in higher top speeds and longer combat ranges. Launching missiles requires opening the weapons bay doors for less than a second, while the missiles are pushed clear of the airframe by hydraulic arms. The aircraft can also carry bombs compatible with the Joint Direct Attack Munition (JDAM) guidance system, and the new Small-Diameter Bomb (SDB). The Raptor carries an M61A2 Vulcan 20 mm rotary cannon, also with a trap door, in the right wing root. The M61A2 is a last ditch weapon, and carries only 480 rounds; enough ammunition for approximately five seconds of sustained fire. Despite this, the F-22 has been able to use its gun in dogfighting without being detected, which can be necessary when missiles are depleted.

The Raptor's very high sustained cruise speed and operational altitude add significantly to the effective range of both air-to-air and air-to-ground munitions. These factors may be the rationale behind the USAF's decision not to pursue long-range, high-energy air-to-air missiles such as the MBDA Meteor. However, the USAF plans to procure the AIM-120D AMRAAM, which will have a significant increase in range compared to the AIM-120C. The Raptor launch platform provides additional energy to the missile which helps improve the range of air-to-ground ordnance. While specific figures remain classified, it is expected that JDAMs employed by F-22s will have twice or more the effective range of munitions dropped by legacy platforms. In testing, a Raptor dropped a 1,000 lb (450 kg) JDAM from 50,000 feet (15,000 m), while cruising at Mach 1.5, striking a moving target 24 miles (39 km) away. The SDB, as employed from the F-22, should see even greater increases in effective range, due to the improved lift to drag ratio of these weapons.

An F-22 releases a JDAM from its center internal bay while flying at supersonic speed.

While in its air-superiority configuration, the F-22 carries its weapons internally, though it is not limited to this option. The wings include four hardpoints, each rated to handle 5,000 lb (2,300 kg). Each hardpoint has a pylon that can carry a detachable 600 gallon fuel tank or a rail launcher that holds two air-air missiles. However, use of external stores compromises the F-22's stealth, and has a detrimental effect on maneuverability, speed, and range. The two inner hardpoints are "plumbed" for external fuel tanks. The hardpoints allow detaching of the mounting pylons in flight so the fighter can regain its stealth after exhausting external stores. Research is currently being conducted to develop a stealth ordnance pod and hardpoints for it. Such a pod would comprise a stealth shape and carry its weapons internally, then would split open when launching a missile or dropping a bomb. Both the pod and hardpoints could be detached when no longer needed. This system would allow the F-22 to carry its maximum ordnance load while remaining stealthy, albeit at a loss of maneuverability.

Stealth

To maintain stealth, the F-22 carries its weapons in internal bays, here shown open.

Although several recent Western fighter aircraft are less detectable on radar than previous designs using techniques such as radar absorbent material-coated S-shaped intake ducts that shield the compressor fan from reflecting radar waves, the F-22 design placed a much higher degree of importance on low observance throughout the entire spectrum of sensors including radar signature, visual, infrared, acoustic, and radio frequency.

The stealth of the F-22 is due to a combination of factors, including the overall shape of the aircraft, the use of radar absorbent material (RAM), and attention to detail such as hinges and pilot helmets that could provide a radar return. However, reduced radar cross section is only one of five facets that designers addressed to create a stealth design in the F-22. The F-22 has also been designed to disguise its infrared emissions to make it harder to detect by infrared homing ("heat seeking") surface-to-air or air-to-air missiles. Designers also made the aircraft less visible to the naked eye, and controlled radio and noise emissions. The Raptor has an under bay carrier made for hiding heat from missile threats, like surface-to-air missiles.

The F-22 apparently relies less on maintenance-intensive radar absorbent material and coatings than previous stealth designs like the F-117. These materials caused deployment problems due to their susceptibility to adverse weather conditions. Unlike the B-2, which requires climate-controlled hangars, the F-22 can undergo repairs on the flight line or in a normal hangar. Furthermore, the F-22 has a warning system (called "Signature Assessment System" or "SAS") which presents warning indicators when routine wear-and-tear have degraded the aircraft's radar signature to the point of requiring more substantial repairs. The exact radar cross section of the F-22 remains classified.

External lighting

The aircraft has integral position and anti-collision lighting (including strobes) on the wings, compatible with stealth requirements, supplied by Goodrich Corporation. The low voltage electroluminescent formation lights are located on the aircraft at critical positions for night flight operations (on both sides of the forward fuselage under the chin, on the tip of the upper left and right wings, and on the outside of both vertical stabilizers). There are similar air refueling lights on the butterfly doors that cover the air refueling receptacle.

Operational history

The 27th Fighter Squadron at Langley Air Force Base was the first squadron to receive the F-22.

Intended to be the leading American advanced tactical fighter in the early part of the 21st century, the Raptor is an expensive fighter with an incremental cost of about US$138 million per unit. The number of aircraft to be built has dropped to 183, down from the initial requirement of 750. Part of the reason for the decrease in the requirement is that the F-35 Lightning II uses technology from the F-22, but at a much more affordable price. To a large extent the cost of these technologies is lower for the F-35 only because they have already been developed for the F-22.

YF-22 "Lightning II"

The prototype YF-22 won a fly-off competition against the Northrop/McDonnell-Douglas YF-23 for the Advanced Tactical Fighter contract. In April 1992 during flight testing after contract award, test pilot Tom Morgenfeld escaped without injury when the first YF-22 prototype that he was flying crashed while landing at Edwards Air Force Base in California. The cause of the crash was found to be a flight control software error that failed to prevent a pilot-induced oscillation.

The YF-22 was a developmental aircraft that led to the F-22; however, there are significant differences between the YF-22 and the F-22. Relocation of cockpit, structural changes, and many other smaller changes exist between the two types. The two are sometimes confused in pictures, often at angles where it is difficult to see certain features. For example, there are some F-22 with pitot booms which some think are only found on the YF-22.

The YF-22 was originally given the unofficial name "Lightning II", after the World War II fighter P-38, by Lockheed, which persisted until the mid-1990s when the USAF officially named the aircraft "Raptor". For a short while, the aircraft was also dubbed "SuperStar" and "Rapier". The F-35 later received the Lightning II name on 7 July 2006.

F-22 Raptor to F/A-22 and back again

The production model was formally named F-22 "Raptor" when the first production-representative aircraft was unveiled on 9 April 1997 at Lockheed-Georgia Co., Marietta, Georgia. First flight occurred on 7 September 1997.

In September 2002, Air Force leaders changed the Raptor’s designation to F/A-22. The new designation, which mimicked that of the Navy’s F/A-18 Hornet, was intended to highlight plans to give the Raptor a ground-attack capability amid intense debate over the relevance of the expensive air-superiority jet. This was later changed back to simply F-22 on 12 December 2005. On 15 December 2005, the F-22A entered service.

Testing

An F-22 refuels from a KC-135 during testing; the attachment on the back top is for a spin recovery chute.

Testing of the F-22 began in 1997 and has been curtailed to save program costs, but risks hiding flaws until a point at which fixing flaws becomes unaffordable. The U.S. General Accounting Office cautioned, "Moreover, engine and stealthiness problems already disclosed by the DoD, and the potential for avionics and software problems, underscore the need to demonstrate the weapon system’s performance through flight testing before significant commitments are made to production."

Raptor 4001 was retired and sent to Wright-Patterson AFB to be fired at for testing the fighter's survivability. Usable parts of 4001 would be used to make a new F-22. Another engineering and manufacturing development (EMD) F-22 was also retired and likely to be sent to be rebuilt. A testing aircraft was converted to a maintenance trainer at Tyndall AFB.

On 3 May 2006, a report was released detailing a problem with a forward titanium boom on the aircraft that was not properly heat treated. Officials are still investigating the problem which was caused by the boom portion not being subjected to high temperatures in the factory for long enough, causing the boom to be less ductile than specified and potentially shortening the lives of the first 80 or so F-22s. Work is underway to restore them to full life expectancy.

The F-22 fleet underwent modifications at Hill AFB, and at Edwards AFB near Palmdale, California.

Recent developments

An F-22 observes as an F-15 Eagle banks left. The F-22 is slated to replace the F-15C/D.

In 2006, the Raptor's development team, composed of Lockheed Martin and over 1,000 other companies, plus the United States Air Force, won the Collier Trophy, American aviation's most prestigious award. The U.S. Air Force will acquire F-22s that are to be divided among seven active duty combat squadrons, and jointly flown and maintained by three integrated Air Force Reserve Command and Air National Guard fighter squadrons.

During Exercise Northern Edge in Alaska in June 2006, 12 F-22s of the 94th FS downed 108 adversaries with no losses in simulated combat exercises. In two weeks of exercises, the Raptor-led Blue Force amassed 241 kills against two losses in air-to-air combat, and neither Blue Force loss was an F-22.

This was followed with the Raptor's first participation in a Red Flag exercise. 14 F-22s of the 94th FS supported attacking Blue Force strike packages as well as engaging in close air support sorties themselves in Red Flag 07-1 between 3 February and 16 February 2007. Against designed superior numbers of Red Force Aggressor F-15s and F-16s, it established air dominance using eight aircraft during day missions and six at night, reportedly defeating the Aggressors quickly and efficiently, even though the exercise rules of engagement allowed for four to five Red Force regenerations of losses but none to Blue Force. Further, no sorties were missed because of maintenance or other failures, and only one Raptor was adjudged lost against the virtual annihilation of the defending force. When their ordnance was expended, the F-22s remained in the exercise area providing electronic surveillance to the Blue Forces.

While attempting its first overseas deployment to the Kadena Air Base in Okinawa, Japan, on 11 February 2007, a group of six Raptors flying from Hickam AFB, Hawaii experienced multiple computer crashes coincident with their crossing of the 180th meridian of longitude (the International Date Line). The computer failures included at least navigation (completely lost) and communication. The fighters were able to return to Hawaii by following their tankers in good weather. The error was fixed within 48 hours and the F-22s continued their journey to Kadena.

In 2007, tests carried out by Northrop Grumman, Lockheed Martin, and L-3 Communications enabled the AESA system of a Raptor to act like a WiFi access point, able to transmit data at 548 Megabit/sec and receive at Gigabit speed; far faster than the current Link 16 system used by US and allied aircraft, which transfers data at just over 1 Megabit/sec.

F-22A Raptors of the 90th Fighter Squadron performed their first intercept of two Russian Tu-95MS 'Bear-H' bombers in Alaska, on 22 November 2007. This was the first time that F-22s had been called to support a NORAD mission.

On 12 December 2007, General John D.W. Corley, USAF, Commander of Air Combat Command, officially declared the F-22s of the integrated active duty 1st Fighter Wing and Virginia Air National Guard 192d Fighter Wing fully operational, three years after the first Raptor arrived at Langley Air Force Base, Virginia. This was followed from 13 April to 19 April 2008 by an Operational Readiness Inspection (ORI) of the integrated wing in which it received an "excellent" rating in all categories while scoring a simulated kill-ratio of 221-0. The first pair of Raptors assigned to the 49th Fighter Wing became operational at Holloman Air Force Base, New Mexico, on 2 June.

In July 2008, F-22s were to be showcased in the 2008 Royal International Air Tattoo air show at RAF Fairford, but did not perform after the show was canceled due to bad weather. An F-22, however, performed on the first day of the Farnborough Airshow on 14 July 2008.

On 28 August, 2008, an F-22 from the 411th Flight Test Squadron performed in the first ever air-to-air refueling of an aircraft using synthetic jet fuel. The test was a part of the wider USAF effort to qualify all of its aircraft to use the fuel, a 50/50 mix of JP-8 and a Fischer-Tropsch process-produced, natural gas-based fuel. For the tests, no modifications were made to the F-22 nor the KC-135 Stratotanker which performed the refueling.


 

posted by Urooj on 10:15 PM under

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AH-64 Apache

The Apache helicopter is a revolutionary development in the history of war. It is essentially a flying tank -- a helicopter designed to survive heavy attack and inflict massive damage. It can zero in on specific targets, day or night, even in terrible weather. As you might expect, it is a terrifying machine to ground forces.

In this article, we'll look at the Apache's amazing flight systems, weapons systems, sensor systems and armor systems. Individually, these components are remarkable pieces of technology. Combined together, they make up an unbelievable fighting machine -- the most lethal helicopter ever created.

At its core, an Apache works pretty much the same way as any other helicopter. It has two rotors that spin several blades. A blade is a tilted airfoil, just like an airplane wing. As it speeds through the air, each blade generates lift. (See How Airplanes Work to find out how lift is generated.)

The main rotor, attached to the top of the helicopter, spins four 20-foot (6-meter) blades. The pilot maneuvers the helicopter by adjusting a swash plate mechanism. The swash plate changes each blade's pitch (tilt) to increase lift. Adjusting the pitch equally for all blades lifts the helicopter straight up and down. Changing the pitch as the blades make their way around the rotation cycle creates uneven lift, causing the helicopter to tilt and fly in a particular direction. (See How Helicopters Work for a full explanation.)

We'll learn more about the rotors and blades next.

Apache Rotors and Blades

As the main rotor spins, it exerts a rotation force on the entire helicopter. The rear rotor blades work against this force -- they push the tail boom in the opposite direction. By changing the pitch of the rear blades, the pilot can rotate the helicopter in either direction or keep it from turning at all. An Apache has double tail rotors, each with two blades.

The newest Apache sports twin General Electric T700-GE-701C turboshaft engines, boasting about 1,700 horsepower each. Each engine turns a drive shaft, which is connected to a simple gear box. The gear box shifts the angle of rotation about 90 degrees and passes the power on to the transmission. The transmission transmits the power to the main rotor assembly and a long shaft leading to the tail rotor. The rotor is optimized to provide much greater agility than you find in a typical helicopter.


­The core structure of each blade consists of five stainless steel arms, called spars, which are surrounded by a fiberglass skeleton. The trailing edge of each blade is covered with a sturdy graphite composite material, while the leading edge is made of titanium. The titanium is strong enough to withstand brushes with trees and other minor obstacles, which is helpful in "nap-of-the-earth" flying (zipping along just above the contours of the ground). Apaches need to fly this way to sneak up on targets and to avoid attack. The rear tail wing helps stabilize the helicopter during nap-of-the-earth flight as well as during hovering.

You could say, based on all this information, that the Apache is just a high-end helicopter. But that would be like calling James Bond's Aston Martin just a high-end car. As we'll see in the next few sections, the Apache's advanced weaponry puts it in an entirely different class.


Apache Hellfire Missiles

The Apache's chief function is to take out heavily armored ground targets, such as tanks and bunkers. To inflict this kind of damage, you need some heavy fire power, and to do it from a helicopter, you need an extremely sophisticated targeting system.

The Apache's primary weapon, the Hellfire missile, meets these demands. Each missile is a miniature aircraft, complete with its own guidance computer, steering control and propulsion system. The payload is a high-explosive, copper-lined-charge warhead powerful enough to burn through the heaviest tank armor in existence.

The Apache carries the missiles on four firing rails attached to pylons mounted to its wings. There are two pylons on each wing, and each pylon can support four missiles, so the Apache can carry as many as 16 missiles at a time. Before launching, each missile receives instructions directly from the helicopter's computer. When the computer transmits the fire signal, the missile sets off the propellant. Once the burning propellant generates about 500 pounds of force, the missile breaks free of the rail. As the missile speeds up, the force of acceleration triggers the arming mechanism. When the missile makes contact with the target, an impact sensor sets off the warhead.

The original Hellfire design uses a laser guidance system to hit its mark. In this system, the Apache gunner aims a high-intensity laser beam at the target (in some situations, ground forces might operate the laser instead). The laser pulses on and off in a particular coded pattern.

The Apache carries the missiles on four firing rails attached to pylons mounted to its wings. There are two pylons on each wing, and each pylon can support four missiles, so the Apache can carry as many as 16 missiles at a time. Before launching, each missile receives instructions directly from the helicopter's computer. When the computer transmits the fire signal, the missile sets off the propellant. Once the burning propellant generates about 500 pounds of force, the missile breaks free of the rail. As the missile speeds up, the force of acceleration triggers the arming mechanism. When the missile makes contact with the target, an impact sensor sets off the warhead.

The original Hellfire design uses a laser guidance system to hit its mark. In this system, the Apache gunner aims a high-intensity laser beam at the target (in some situations, ground forces might operate the laser instead). The laser pulses on and off in a particular coded pattern.

The laser-guided Hellfire system is highly effective, but it has some significant drawbacks:

  • Cloud cover or obstacles can block the laser beam so it never makes it to the target.
  • If the missile passes through a cloud, it can lose sight of the target.
  • The helicopter (or a ground targeting crew) has to keep the laser fixed on the target until the missile makes contact. This means the helicopter has to be out in the open, vulnerable to attack.

The Hellfire II, used in Apache Longbow helicopters, corrects these flaws. Instead of a laser-seeking system, the missile has a radar seeker. The helicopter's radar locates the target, and the missiles zero in on it. Since radio waves aren't obscured by clouds or obstacles, the missile is more likely to find its target. Since it doesn't have to keep the laser focused on the target, the helicopter can fire the missile and immediately find cover.

We'll look at the Apache's rockets next.


Apache Rockets and Chain Gun

Apaches usually fly with two Hydra rocket launchers in place of two of the Hellfire missile sets. Each rocket launcher carries 19 folding-fin 2.75-inch aerial rockets, secured in launching tubes. To fire the rockets, the launcher triggers an igniter at the rear end of the tube. The Apache gunner can fire one rocket at a time or launch them in groups. The flight fins unfold to stabilize the rocket once it leaves the launcher.


The rockets work with a variety of warhead designs. For example, they might be armed with high-power explosives or just smoke-producing materials. In one configuration, the warhead delivers several submunitions, small bombs that separate from the rocket in the air and fall on targets below.

The gunner engages close-range targets with an M230 30-mm automatic cannon attached to a turret under the helicopter's nose. The gunner aims the gun using a sophisticated computer system in the cockpit. The computer controls hydraulics that swing the turret from side to side and up and down.

The automatic cannon is a chain gun design, powered by an electric motor. The motor rotates the chain, which slides the bolt assembly back and forth to load, fire, extract and eject cartridges. This is different from an ordinary machine gun, which uses the force of the cartridge explosion or flying bullet to move the bolt.


The cartridges travel from a magazine above the gun down a feed chute to the chamber. The magazine holds a maximum of 1,200 rounds, and the gun can fire 600 to 650 rounds a minute. The cannon fires high-explosive rounds designed to pierce light armor.

In the next section, we'll look at the targeting system for the cannon, as well as the other major Apache controls.

 

posted by Urooj on 10:14 PM under

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