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Thursday 6 April 2017

F-35 Lighting II

                     F-35 Lighting II

Introduction :

The Lockheed Martin F-35 Lightning II is a 5th Generation single-seat, single-engine, all-weather stealth multirole fighters .

🔵Role : Multirole Fighter 
🔵Origin : United States 
🔵Manufacturer : Lockheed Martin 
🔵Introduction : F-35B (2016),  F-35A (2015)
🔵Produced : In America 
🔵Quantity : 200
🔵Unit Cost : US$ 90 Million To  Million 

F-35 Specifications :

⭕Crew : 1 
⭕Length : 15 m
⭕Wingspan : 11 m
⭕Height : 4 m
⭕Wing Area : 43 m²
⭕Empty Weight : 13,200 kg
⭕Max Takeoff Weight : 32,200 kg
⭕Fuel Capacity : 8,382 kg

Operators :

The operators of F-35 Lightning II are United States, Australia, Denmark, Israel, Italy, Japan, Netherlands, Norway, Turkey Currently. 

Production :

The F-35 descends from the X-35 , the winning design of the Joint Strike Fighter (JSF) program. An aerospace industry team led by Lockheed Martin designed and manufactures it. Other major F-35 industry partners include Northrop Grumman, Pratt & Whitney and BAE Systems . The F-35 first flew on 15 December 2006. The United States plans to buy 2,457 aircraft. Its variants are to provide the bulk of the crewed tactical airpower of the U.S. Air Force , Navy and the Marine Corps over the coming decades. Deliveries of the F-35 for the U.S. military are scheduled until 2037 with a projected service life up to 2070. The United States principally funds the F-35 JSF development, with additional funding from partners. The partner nations are either NATO members or close U.S. allies. The United Kingdom, Italy, Australia, Canada, Norway, Denmark, the Netherlands, and Turkey are part of the active development program; several additional countries have ordered, or are considering ordering, the F-35.The program is the most expensive military weapons system in history, and has been much criticized inside and outside government, in the U.S. and in allied countries. Critics argue that the plane is "plagued with design flaws," with many blaming the procurement process in which Lockheed was allowed "to design, test, and produce the F-35 all at the same time, instead of… [identifying and fixing] defects before firing up its production line." By 2014, the program was "$163 billion over budget and seven years behind scheduleThe JSF development contract was signed on 16 November 1996, and the contract for System Development and Demonstration (SDD) was awarded by the Department of Defense (DoD) on 26 October 2001 to Lockheed Martin, whose X-35 beat the Boeing X-32 . Although both aircraft met or exceeded requirements, the X-35 design was considered to have less risk and more growth potential.Based on wind tunnel testing, Lockheed Martin slightly enlarged its X-35 design into the F-35. The forward fuselage is 5 inches longer to make room for avionics. Correspondingly, the horizontal stabilators were moved 2 inches rearward to retain balance and control. The top surface of the fuselage was raised by 1 inch along the center line. Also, it was decided to increase the size of the F-35B STOVL variant's weapons bay to be common with the other two variants.  Manufacturing of parts for the first F-35 prototype airframe began in November 2003. Because the X-35 did not have weapons bays, their addition in the F-35 would cause design changes which would lead to later weight problems.The F-35B STOVL variant was in danger of missing performance requirements in 2004 because it weighed too much; reportedly, by 1,000 kg or 8 percent. In response, Lockheed Martin added engine thrust and thinned airframe members; reduced the size of the common weapons bay and vertical stabilizers; re-routed some thrust from the roll-post outlets to the main nozzle; and redesigned the wing-mate joint, portions of the electrical system, and the portion of the aircraft immediately behind the cockpit. Many of the changes were applied to all three variants to maintain high levels of commonality. By September 2004, the weight reduction effort had reduced the aircraft's design weight by 1,200 kg, but the redesign cost $6.2 billion and delayed the project by 18 months.F-35 had many delays due to political, economic and international sophisticated problems but finaly it came into being after many improvements.In early 2015 the AF-2 F-35A, the primary flight sciences loads and flutter evaluation aircraft, was flown by Lockheed Martin F-35 site lead test pilot David "Doc" Nelson in air-to-air combat maneuvers against F-16s for the first time and, based on the results of these and earlier flight-envelope evaluations, said the aircraft can be cleared for greater agility as a growth option. AF-2 was the first F-35 to be flown to 9g+ and −3g, and to roll at design-load factor. Departure/spin resistance was also proven during high angle-of-attack (AOA) testing which eventually went as high as 110 deg. AOA. "When we did the first dogfight in January, they said, ‘you have no limits,’" says Nelson. "It was loads monitoring, so they could tell if we ever broke something. It was a confidence builder for the rest of the fleet because there is no real difference structurally between AF-2 and the rest of the airplanes." "Pilots really like maneuverability, and the fact that the aircraft recovers so well from a departure allows us to say [to the designers of the flight control system laws], ‘you don’t have to clamp down so tight,’" says Nelson.With the full flight envelope now opened to an altitude of 50,000 ft, speeds of Mach 1.6/700 KCAS and loads of 9 g, test pilots also say improvements to the flight control system have rendered the transonic roll-off (TRO) issue tactically irrelevant. Highlighted as a "program concern" in the Defense Department’s Director of Operational Test and Evaluation (DOT&E) 2014 report, initial flight tests showed that all three F-35 variants experienced some form of wing drop in high-speed turns associated with asymmetrical movements of shock waves. However, TRO "has evolved into a non-factor," says Nelson, who likens the effect to a momentary "tug" on one shoulder harness. "You have to pull high-g to even find it." The roll-off phenomena exhibits itself as "less than 10 deg./sec. for a fraction of a second. We have been looking for a task it affects and we can’t find one.In July 2015, Lockheed Martin confirmed the authenticity of a leaked report showing the F-35 to be less maneuverable than an older F-16D with wing tanks.The pilot who flew the mission reported inferior energy , a limited pitch rate and flying qualities that were "not intuitive or favorable" in a major part of the air-combat regime gave the F-16 the tactical advantage. In general the high AoA capabilities of the jet could not be used in an effective way without significantly reducing follow-on maneuvering potential. In an interview with CBC Radio broadcast 2 July 2015, military journalist David Axe claimed to have read the leaked report and stated: "Against a determined foe, the F-35 is in very big trouble."However, the F-35 used was a flight test aircraft with a restricted flight envelope and lacked some features present on the operational aircraft. The Pentagon, JPO, and defense analysts have defended the F-35's utility in spite of the report's assertion that it lacks maneuverability by saying it was designed primarily to disrupt the kill chain of advanced air defenses while the F-22 would handle close-in dogfighting, it has advanced sensor and information fusion capabilities to detect and engage enemy aircraft at long ranges before it can be seen and merged with, and that most air combat in recent decades has focused on sensors and weapons that achieved long-range kills rather than close combat.

Versions :

The F-35A is the conventional takeoff and landing variant intended for the U.S. 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 AV-8B Harrier II. It is designed for increased effectiveness against ground targets compared to the 20 mm M61 VULCAN cannon carried by other USAF fightersThe F-35A is expected to match the F-16 in maneuverability and instantaneous high-g performance, and outperform it in stealth, payload, range on internal fuel, avionics, operational effectiveness, supportability, and survivability.It is expected to match an F-16 that is carrying the usual external fuel tank in acceleration performance.The A variant is primarily intended to replace the F-16. At one point it was also intended to replace A-10 Thunderbolt II starting in 2028. The F-35A can be outfitted to receive fuel via either of the two main aerial refueling methods; this was a consideration in the Canadian procurement and a deciding factor for the Japanese purchase. On 18 December 2013, the Netherlands became the second partner country to operate the F-35A, when Maj. Laurens J.W. Vijge of the Royal Netherlands Air Force  took off from Eglin Air Force Base.On 27 January 2014, General Mike Hostage,  head of Air Combat Command , stated he would fight "to the death" to not have a single plane of the USAF's planned 1,763 F-35 purchase be cut, because the allies and partners of the US got "weak in the knees" when seeing the USAF "back away" from the F-35. He said the F-15 and F-16 fleets would become tactically obsolete in the middle of the next decade regardless of improvements. Hostage also commented that the F-35 would be "irrelevant" without the F-22 fleet being viable as the F-35 was not an air superiority fighter,and that an F-35 pilot who enters a dogfight has made a mistake.The F-35As for the Royal Norway Air Force  will have drag chute installed. Norway will be the first country to adopt the drag chute pod.On 2 August 2016, the U.S. Air Force declared the F-35A basic combat ready. F-35A is scheduled to be full combat ready in 2017 with its 3F software upgrade. Air Combat Command will initially deploy F-35A to Red Flaf exercises and as a "theater security package" to Europe and the Asia-Pacific. It will probably not be fighting the Islamic state in the Middle East earlier than 2017, but ACC commander General wouldn't mind deploying them earlier.


The F-35B is the short takeoff and vertical landing variant of the aircraft. Similar in size to the A variant, the B sacrifices about a third of the A variant's fuel volume to accommodate the vertical flight system . Vertical takeoffs and landings are riskier because of threats such as foreign object damage Commandant of the U.S. Marine Corps, General James Amos has said that, in spite of increasing costs and schedule delays, there is no plan B to the F-35B. The F-35B is larger than the aircraft it replaces, which required USS America to be designed without well deck capabilities.In 2011, the USMC and USN signed an agreement by which the USMC will purchase 340 F-35B and 80 F-35C fighters, while the USN will purchase 260 F-35Cs. The five squadrons of USMC F-35Cs will be assigned to Navy carriers; F-35Bs will be used on amphibious ships and ashore.


The F-35C carrier variant features larger wings  foldable wingtip sections, larger wing and tail control surfaces for improved low-speed control, stronger landing gear for the stresses of carrier arrested landings, a twin-wheel nose gear, and stronger tailhook for use with  arrestor cables. The larger wing area allows for decreased landing speed while increasing both range and payload.The United States Navy intends to buy 480 F-35Cs to replace the F/A-18A, B, C, and D Hornets and complement the Super Hornet fleet. On 27 June 2007, the F-35C completed its Air System Critical Design Review (CDR), allowing the production of the first two functional prototypes.The C variants expected to be available beginning in 2014.The first F-35C was rolled out on 29 July 2009.The United States Marine Corps will also purchase 80 F-35Cs, enough for five squadrons, for use with navy carrier air wings in a joint service agreement signed on 14 March 2011.

Engines:

The Pratt & Whitney F135 powers the F-35. An alternative engine, the General Electric/Rolls-Royce, was being developed until it was cancelled by its manufacturers in December 2011 for lack of funding from the Pentagon.The F135 and F136 engines are not designed to super cruise.  However, the F-35 can briefly fly at Mach 1.2 for 150 miles.The F135 is the second (radar) stealthy afterburning jet engine. Like the Pratt & Whitney F1190  from which it was derived, the F135 has suffered afterburner pressure pulsations, or 'screech' at low altitude and high speed. The F-35 has a maximum speed of over Mach 1.6. With a maximum takeoff weight of 60,000 lb (27,000 kg),the Lightning II is considerably heavier than the lightweight fighters it replaces.The STOVL F-35B is outfitted Rolls-Royce Lift System , designed by Lockheed Martin and developed by Rolls-Royce. This system more resembles the German VJ 101D/Ethan the preceding STOVL Harrier Jump Jet and the Royal-Royce Pegasus engine.The Lift System is composed of a lift fan, drive shaft, two roll posts and a "Three Bearing Swivel Module" (3BSM). The 3BSM is a thrust verctoring nozzles  which allows the main engine exhaust to be deflected downward at the tail of the aircraft. The lift fan is near the front of the aircraft and provides a counterbalancing thrust using two counter-rotating blisks.It is powered by the engine's low-pressure (LP) turbine via a drive shaft and gearbox. Roll control during slow flight is achieved by diverting unheated by pass air through wing-mounted thrust nozzles called Roll Posts.

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