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Thread: The Pentagon's 399 billion plane nowhere

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  1. #21
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    Re: Is F-35 a blunder?

    Quote Originally Posted by Fassi View Post
    With drones and lasers satellites you are right current thinking might already be in the past
    Spot on that is the future of warfare

  2. #22
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    “Pursue one great decisive aim with force and determination.”
    - Carl von Clausewitz

  3. #23
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    Re: Is F-35 a blunder?

    In November 1994 the United States merged the Joint Advanced Strike Technology and Common Affordable Lightweight Fighter programmes to create the JSF programme. Low observable technology, powerful sensors, net-centric capabilities, internal weapons carriage, a high-thrust engine and manoeuvrability would enable the resultant aircraft to undertake both air-to-air and air-to-ground missions with a high degree of survivability. Equally important was affordability, allowing the US military to replace its existing inventory on a one-for-one basis. A conventional take-off and landing (CTOL) version would replace most of the US Air Force’s inventory of fi ghter-bombers, while a carrier variant (CV) would supplant the US Navy’s F/A-18 Hornets at sea. The US Marine Corps would replace its AV-8B Harrier IIs with a short take-off and vertical landing (STOVL) variant of the JSF. Currently the US Air Force
    plans to acquire 1,763 examples, and the US Navy and Marine Corps 760, while exports are likely to raise production to more than 3,100 by 2035. Industrial interest in JSF was high from the start given the numbers involved and most of the major players submitted proposals for a four-year weapons system concept demonstration (WSCD) phase, requests for which were released in December 1995. WSCD sought two competing teams to build two demonstrators and later modify one into the third variant to prove the commonality between the CTOL, STOVL and CV variants. In November 1996 Boeing was informed it would produce two X-32s, and Lockheed Martin two X-35s. Subsequently Northrop Grumman and British Aerospace joined Lockheed Martin’s team.

    Demonstrators
    The X-35A CTOL demonstrator (Article 301) fi rst fl ew from Palmdale, California, on October 24, 2000, and was tested at Edwards AFB, California, until November 22, when it returned to Palmdale for installation of a lift fan during its conversion to become the X-35B STOVL demonstrator. It commenced hover pit trials in February 2001 and made its fi rst vertical take-off and landing on June 23, 2001. The X-35C (Article 300) was the CV demonstrator and fi rst fl ew on December 16, 2000.After the US Department of Defense evaluated both the X-32 and X-35, on October 26, 2001, Lockheed Martin was selected to enter the system development and demonstration
    (SDD) phase, and the designations F-35A, F-35B and F-35C were allocated to production
    CTOL, STOVL and CV variants respectively. In addition to the baseline versions, an electronic
    attack variant of the F-35C – the ‘EF-35B’ – is required (but currently unfunded) by the Marines. In mid-2006 unmanned and optionally manned versions were proposed by Lockheed Martin.To fund development, the US Department of Defense offered foreign nations involvement in the programme at different levels, depending on their fi nancial contributions. Those at Level 1, funding 10% of the costs, and Level 2 (around 5%), could directly receive contracts related to the F-35, while Level 3 (1 to 2%) could look forward to contracts from Level 1/2 nations. Security Co-operation Participants (SCP) are entitled to data on the programme in exchange for approximately $50 million. The only Level 1 nation is the UK, with Italy and the Netherlands at Level 2, and Australia, Canada, Denmark, Norway and Turkey at Level 3. Israel and Singapore joined as SCP nations.

  4. #24
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    Re: Is F-35 a blunder?

    Flight Testing
    SDD was due to involve 15 (later reduced to 13) instrumented test aircraft and seven ground test airframes, two of each variant plus another for radar signature evaluation. In addition the co-operative avionics testbed (CAT-bird), a modifi ed Boeing 737-300, would test the F-35’s mission systems. Flight trials are undertaken by Lockheed Martin at Fort Worth, and by industry and service teams at Edwards AFB, California, and NAS Patuxent River, Maryland. AA-1, the first F-35A rolled off the production line at Fort Worth, Texas, on February 19, 2006, and was formally unveiled on July 7 at a ceremony during which the aircraft was named the Lightning II. It completed its maiden flight on December 15, 2006. Weight reduction measures and other redesigns made AA-1 non-representative of the planned production standard, but were incorporated into the others produced for SDD.The second to fl y was the fi rst F-35B (BF-01) on June 11, 2008, followed by BF-02 on February 25, 2009. On November 14, 2009, the initial optimised F-35A (AF-01) was fl own, while the fi rst F-35C (CF-01) took off for its maiden fl ight on June 7, 2010, the eighth Lightning II to enter the test programme. BF-04 became the fi rst equipped with the complete mission system, fl ying on April 7, 2010. By early March 2011 a total of eleven pre-production aircraft had fl own, plus two F-35As from low rate initial production 1 (LRIP 1). The LRIP 1 aircraft (AF-06 07-0744 and AF-07 07-0745) joined the fl ight programme on February 25 and March 4 respectively, both carrying markings for the 33rd Fighter Wing at Eglin AFB, Florida, responsible for the training of service pilots and ground crews on the aircraft.Early production aircraft were due to be delivered with Block 1 software, allowing them to employ Joint Direct Attack Munitions and AIM-120 AMRAAM missiles, but initial deliveries will use Block 0.5, originally intended only for training and test support activities. Block 2 will add further capability, while Block 3 will be the initial operating capability (IOC) standard.

    Challenges Ahead
    While the JSF programme has come a long way, some signifi cant hurdles remain. Delays caused by design alterations and inevitable problems discovered during flight testing will make it difficult for the aircraft to meet its IOC within the current timeframe. Initially the F-35B had an IOC of 2012, but development of this variant has proved more troublesome than the other two. In January 2011 it was put on a two-year ‘probation’ during which its engineering deficits will need to be overcome before its future is secured. IOC for the F-35A and F-35C is set for 2013. This is before initial operational test and evaluation (IOT&E) is concluded in November 2015 – an unparalleled situation, brought about by the delays. IOT&E completion is 13 months behind the original schedule established in May 2008, and four years later than originally set out in 2001. Milestone C, which signals the end of LRIP and allows multiyear buys, cannot be declared until operational testing is completed. It is currently planned for 2016.The biggest uncertainty, however, is the cost of the F-35. Original plans for an F-16-priced aircraft have long since been forgotten, with some analysts suggesting the actual cost is closer to that of the top-end F-22 Raptor. Export customers also have issues with technology transfer, including access to source codes, without which their ability to perform indigenous service upgrades would be severely curtailed.Lockheed Martin began initial fl ight testing of the F-35 in 2006 with aircraft AA-1, the fi rst F-35A CTOL variant. The primary role of AA-1 was to prove the feasibility of major new systems integrated on the F-35 as part of a risk reduction effort.Systems include the electro-hydro static actuator (see Electric Muscle), the electrical system and the integrated power pack: “All of which have new and unique things that no one has done before, so we had to reduce the risk on all of them,” said Beesley. Other systems fl own on AA-1 as part of the risk reduction effort included the engine control system, the panoramic glass cockpit and the helmet mounted display. Speaking about the fl ight testing, Jon Beesley told AIR International: “We undertook aero strut testing, fl ew supersonic, opened the weapons bay doors during fl ight and fl ew the aircraft with a full internal combat weapons load, all of which were undertaken to discover problems and reduce the risk to the programme.”AA-1 also completed a series of cable engagements to verify the design of the tail hook before its retirement after 90 fl ights.F-35s currently being used in the fl ight test programme for the system development and demonstration (SDD) phase were modified or built to a revised gross weight configuration. This design change followed the SWAT (STOVL Weight Attack Team) weight optimization effort launched by Lockheed Martin in February 2004. This effort sought to reduce the gross weight of the original F-35B design by 3,000lb (1,360kg) and the changes that were made had benefi cial effects to the aircraft in the conventional and STOVL modes of fl ight. “We done a lot of ground testing in the STOVL mode with the lift fan engaged and spent several months on the instrumented hover pit to measure force and moments,” said Beesley.“We found that the force from the aeroplane was a bit better than we had thought, so a nice surprise. We also looked at the mechanical issues associated with controlling the aircraft in the STOVL mode. Making the aeroplane transform from conventional fl ight mode into STOVL mode is really incredible and requires a lot of complex mechanization.
    Last edited by Jagga; 16th July 2014 at 02:56.

  5. #25
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    Re: Is F-35 a blunder?

    Electric Muscle
    One revolutionary system on the F-35 is the electro-hydrostatic actuator (EHA), which are used to power the fl ight controls. Jon Beesley is enthusiastic about the use of the EHA: “The F-16, Typhoon, even Raptor all have ‘electric brains’ and ‘hydraulic muscle’, but the F-35 has electric muscle. Nobody has really done that before. We fl ew AA-1 and learned how to improve on the original design that was incorporated into the other aeroplanes.”But the electric nature of the F-35 also includes the integrated power pack (IPP), a new type of system that removes the need to have an APU (auxiliary power unit, a turbine) as typically used by a legacy aircraft, to start the engine(s). Similarly the environmental control, pressurization and air conditioning systems on legacy jets are also powered by another turbine run on bleed air, and in the case of single engine aircraft like the F-16 a third turbine run on hydrazine is used as an emergency power unit. “On the F-35 we have the IPP and use it to start the aeroplane (like an APU) and switch it over to the environmental control system and then we can run it either off the engine and use bleed air as an air emergency generation system, or we start it in the air in the fuel mode and run it that way. Nobody has done that before, and quite honestly those three systems [APU, environmental control and emergency power] were the biggest problem in the first two or three years of fl ying the Raptor,” said Beesley.

    STOVL Trials
    BF-01 fi rst fl ew its airworthiness fl ights in June 2008 a process that continued for longer than planned while modifi cations took place ahead of the hover pit testing in October.Using fl ight test aides fi tted on the aeroplane, Beesley and his test pilot colleagues were able to open the doors in various sequences primarily for structural reasons to determine the loads induced upon the doors in fl ight. As a result Beesley and his team found the aerodynamic effect was worse than originally thought. Lockheed Martin engineers adjusted the fl ight control laws applied to the aircraft to accommodate the aerodynamic differences encountered during the early fl ights. Flying the F-35B with the doors open provided data that allowed the engineers to study the changes and in the way the computer controls the aeroplane. This analysis led to a better understanding of the aerodynamic effect with the doors in the open position that allowed tighter fl ight control to be achieved.The fl ights were all undertaken without the lift fan engaged; “Which is clearly the worst situation, with the upper lift fan door up, you get a tremendous amount of effect, which only turns benefi cial when you start to fl ow a lot of air through the fan. Before that, the air has no place to go and tends to degrade aerodynamic performance,” said Beesley.

  6. #26
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    Re: Is F-35 a blunder?

    Pit Testing
    In late March 2009, Lockheed Martin commenced hover pit testing using a purpose built facility at its Fort Worth plant. Jon Beesley explained: “It is a graded pit so there are no ground effects and the air exits at another place, so it is really a free airborne test.“We chained the aircraft down on the load measurement system [a large equivalent of bathroom scales] and ran the aircraft all the way to full power with the thrust pointed at various angles to simulate all of the various facets of fl ying. The obvious ones are vertical lift, but we also simulated short take-off and short landing profi les.Beesley and the test team also tested the rates at which the actuators worked and the response of the fl ight control surfaces. This was undertaken to determine whether controls were providing the equivalent performance to that used by the engineers in their analysis. Other tests studied the effectiveness of the roll-posts (see Powering the Lightning II) .“We also placed plates over the pit to see the resultant effect on the ground and on the bottom of the aeroplane during vertical take-offs and landings. The thermal effects on the aeroplane certainly matched what the engineers had predicted,” said Beesley.Thrust was one of the primary reasons for the pit tests. According to Jon Beesley the engine demonstrated greater thrust than was expected and the aircraft handled very well throughout the test campaign.

  7. #27
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    Re: Is F-35 a blunder?

    Handling Characteristics
    When asked about the differences in handling characteristics between the F-35A and the F-35B Jon Beesley said that the two variants differed only slightly in the conventional mode applicable to each. In terms of manoeuvrability the two handle exactly the same because of the control laws applied to counter the different aerodynamic characteristics of each variant.Aircraft AF-01 and BF-01 are closer in terms of handling than AA-1 and BF-01, which according to Lockheed Martin is caused by the differences in the landing gear. Pilots encountered a challenge with AA-1 on the early fl ights. The movement arm between the landing gear and the tail was too short causing the aircraft to rotate a little faster than it should to achieve the best take-off. As part of the SWAT effort, the landing gear was canted forward by 5 inches (125mm), which “makes a world of difference,” said Beesley.The F-35C CV variant has a bigger wing so the main handling difference is felt during take-off and landings, which are 15-20 knots (28-37km/h) slower because of its heavier weight, bigger stabilators and greater down force. Other differences are associated with, and specifi c to carrier operations. But the design goals of all three variants remain the same: “We want an aeroplane that a pilot could [in theory] go from fl ying a CTOL in the morning to a STOVL in the afternoon and the CV in the evening and would be comfortable in all three because of similarity,” said Beesley.“We have gone to great lengths to make the aeroplane easy to perform STOVL operations. That is very hard to do, but the guys have done some really brilliant work capitalising on a concept developed on the VAAC Harrier at Boscombe Down called the unifi ed control law, a technique that makes conversion to the F-35B and STOVL operations very straightforward.” So much so that a pilot’s primary focus during training will be on the tactical aspects of the mission as opposed to vertical landing technique.

  8. #28
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    Re: Is F-35 a blunder?

    Performance of the Aircraft
    According to the test pilots that spoke with AIR International the performance they fi rst experienced in the F-35 was more than expected. “On my fi rst fl ight in AA-1, I found myself climbing out with the gear down much steeper than I thought,” said Beesley adding: “When I did supersonic testing carrying two 2,000lb bombs and two missiles, the aircraft had no trouble at all getting there [to supersonic fl ight] which is really quite an accomplishment, the F-16 chase aircraft was occasionally tapping the afterburner to keep up.” He enthused about its performance, citing examples in which the aircraft performed very well fl ying at low level with the doors open, or at 450 knots (830km/h) at 10,000ft (3,048m) with the doors open, up to Mach 1.1, and to 500 knots (925km/h) at 10,000ft with the doors closed. The F-35 is designed to perform a huge variety of missions with stealth: air-to-air, interdiction, and when the battlefi eld environment is permissive, close air support with munitions carried on external weapons stations. Performance-wise, an F-35 with a full internal-load of weapons is comparable to a fourth generation aircraft like an F-16 with no weapons at all.And in terms of manoeuvrability the F-35 will be cleared to a 50° angle of attack, similar to the F/A-18 Hornet, with a full load of munitions (two 2,000lb precision-guided weapons or eight small diameter bombs) inside.Most of the test fl ights are fl own at 30,000-32,000ft (9,144-9,753m) but the aircraft has a 50,000ft (15,240m) ceiling and will be optimized for the block 20,000-40,000ft (6,096-12,192m).

  9. #29
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    Re: Is F-35 a blunder?

    Challenge for the Fifth Generation
    There are people who maintain that the F-35 is an unnecessary weapon system. When the author discussed this with Jon Beesley he shared his own view: “Lockheed Martin was asked to build a combat aircraft to address a very real need. Sometimes people conjecture, typically without much knowledge, that threats will evolve to negate the things that fi fth generation aeroplanes bring. Well, anything that will not work because of the physics involved, against a fi fth generation aeroplane will be an order of magnitude more effective against a current generation aeroplane, and so that argument says that you should have probably done it sooner, and should do it more.”In terms of evolution the sensors on the F-35 will provide the pilot with answers rather than just data, which will allow him or her to do what is most important – think. And the answers presented by the fusion system can be shared across the network to enhance the situational awareness in the battlefi eld all from a stealthy aircraft.In the convoluted development history of the F-35 Lightning II, no issues have drawn more public attention than those involving the aircraft’s propulsion systems. These have been among the most contentious aspects of the F-35’s development, from the long political battle over whether it is to have one engine type or two, to the threat of programme cancellation hanging over the STOVL F-35B.But whatever political challenges the F-35 faces, the technological advances achieved by Pratt & Whitney in developing the F135 – the engine of record for the F-35 Lightning II – and by Rolls-Royce in developing the STOVL F-35B’s extraordinary LiftSystem have been immense.

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    Re: Is F-35 a blunder?

    The Pratt & Whitney F135
    Chosen on October 26, 2001, by the US Department of Defense (DoD) for a $4 billion system development and demonstration (SDD) contract which decided the Pratt & Whitney F135 would be used for all F-35 development fl ight-testing, the F135 is a bigger-diameter, higher-airfl ow derivative of the company’s F119 engine powering the F-22 Raptor. The F135 was chosen for the SDD contract because both Lockheed Martin and Boeing had selected it (in the form of augmented F119s) to power their respective X-35 and X-32 Joint Strike Fighter (JSF) demonstrators, Lockheed Martin winning the JSF contract with its X-35. The Pentagon also found attractive the fact that the F135 shared a high degree of commonality with the F119, two of which power each F-22Raptor.
    The F135 and F119 are both axial-fl ow engines (air goes through the core of the engine in a straight line) and they share a “highly common core”, according to Ed O’Donnell,Business Development Director for Pratt & Whitney’s F135 and F119 programmes. From front to back, these two-spool engines are “largely common through the compression system,” says O’Donnell – noting, however, that the commonality is mainly in the fi rm of shared engine architecture rather than common part numbers. Part numbers for the F135 have been designated differently to those for similar parts in the F119 because the US services want to be able to allocate specifi c part numbers to specifi c programmes for inventory-management reasons.Despite their similarities, there are some crucial differences between the F135 and the F119. One is that the F135 needs to be able to generate up to 43,000lb (191.27kN)of thrust ‘wet’ (with afterburner) for the single-engine F-35, whereas the F119 provides a lesser 35,000lb (155.7kN) of thrust with full afterburner. As a result the F135 has a larger inlet diameter (46 inches/1,168mm), larger fan diameter (50 inches/1,270mm) and larger overall engine diameter (51 inches/1,295mm) than does the F119, so it can achieve a higher airfl ow.Like the F119, the F135 has a three-stage fan (in military-engine parlance, the fan is the entire low-pressure compressor assembly). Each fan stage comprises a one-piece integrally bladed rotor (or ‘blisk’, short for bladed disc) featuring a solid titanium hub with titanium blades welded on to it. The fi rst fan stage has hollow titanium blades and each of the subsequent two stages has solid titanium blades. Aft of the third fan stage the accelerated airfl ow is split, 57% of it going through the fan duct as bypass air and the remaining 48% entering the core to be compressed, mixed with fuel, ignited and then exhausted as hot gas to turn the turbine stages and produce up to 28,000lb (124.55kn) of dry thrust before afterburner.The F135 has a six-stage high-pressure compressor (HPC) and again each stage is comprises a blisk. Some of the initial HPC stages are made from titanium but because the airfl ow becomes hotter as it passes through each stage of compression, one or more later HPC stages are made from nickel-based alloy to be able to withstand the high air temperature. In conventional F-35 fl ight, air exiting the HPC into the combustor is at 28 times the pressure it was when entering the fan and it is at 29 times the pressure when the F-35B is in hover mode.The engine’s single annular combustor features removable liners and a series of fuel nozzles, all housed within a diffuser case. O’Donnell says the F135 combustor is “highly similar” to that in the F119, but features “some improvements to accommodate the appropriate temperature requirements” of the higher-power F135. Overall, the cores of the two engines – the region from HPC to combustor to HPT – are essentially the same size and since the F135 has to produce more dry power at full thrust than the F119 it is likely to run hotter than the F119.While both the F119 and the F135 feature a single-stage high-pressure turbine (HPT), the F135 has a two-stage low-pressure turbine (LPT) where the F119 has a single-stage LPT. This is because, in the F-35B STOVL aircraft, the low-pressure spool to which the LPT is attached has to drive not only the fan stages but also the driveshaft powering the Rolls-Royce LiftFan located behind the cockpit and ahead of the engine.The LiftFan (one of three major components of the Rolls-Royce LiftSystem, which provides the F-35B’s hover capability) is not engaged while in normal forward fl ight and does not feature at all in the F-35A CTOL and F-35C CV conventional take-off and landing variants of the Lightning II. However, from the outset the specifi cation for the F-35’s engine called for “tri-variant compatibility”: the engine powering an F-35A is identical to that powering an F-35B or an F-35C. Nevertheless, the engines are designated differently: the F-35A powerplant is the F135-PW-100; the engine for the F-35C is the F135-PW-400; and the F-35B engine is the F135-PW-600. Since the F-35B powerplant needs an extra LPT stage to provide the power necessary to turn the driveshaft (which, through a clutch and gearbox, drives the LiftFan), F135s built to power other F-35 variants have the second LPT stage as well. “The engine was designed to support that severe STOVL requirement,” says O’Donnell. For engines powering CTOL F-35As and F-35Cs, the additional turbine stage offers a substantial extra power margin, allowing for potential F-35 weight growth. Since the engine isn’t heavily taxed in many CTOL missions, its maintainability is improved too.The geometries of the cooling-air paths and airfl ows in the F135’s hot section are different from those in the F119. Turbine-blade coating materials, used to prevent nickel-alloy turbine blades and vanes from melting in the several-thousand-degrees airfl ow coming from the combustor, may well have been updated too. P&W may be able to apply retroactively to production F119s the advances in cooling-path and coating technologies it devised for the F135.In both engines, cooling air is taken from the bypass airfl ow and by bleeding air away from the HPC stages to cool the HPT and LPT stages, probably by means of air channels etched into their blades and into the turbine casing, as is the case in commercial turbofans. “Even fi fteen-hundred-degree air is cooling air if it’s relative to hotter air,” notes O’Donnell. “The [blade] metal melts at the temperatures we’re operating at and a lot of the technology is in the cooling and coatings.”
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  11. #31
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    Pentagon’s big budget F-35 fighter ‘can’t turn, can’t climb, can’t run'

    Americans should be worried.

    The U.S. military has grounded all its new F-35 Joint Strike Fighters following an incident on June 23, when one of the high-tech warplanes caught fire on the runway of a Florida air base. The no-fly order — which affects at least 50 F-35s at training and test bases in Florida, Arizona, California and Maryland — began on the evening of July 3 and continued through July 11.

    All those F-35s sitting idle could be a preview of a future in which potentially thousands of the Pentagon’s warplanes can’t reliably fly.

    Handout photo of three F-35 Joint Strike Fighters flying over Edwards Air Force BaseTo be fair, the Pentagon routinely grounds warplanes on a temporary basis following accidents and malfunctions to buy investigators time to identify problems and to give engineers time to fix them.

    But there’s real reason to worry. The June incident might reflect serious design flaws that could render the F-35 unsuitable for combat.

    For starters, the Lockheed Martin-built F-35 — which can avoid sensor detection thanks to its special shape and coating — simply doesn’t work very well. The Pentagon has had to temporarily ground F-35s no fewer than 13 times since 2007, mostly due to problems with the plane’s Pratt & Whitney-made F135 engine, in particular, with the engines’ turbine blades. The stand-downs lasted at most a few weeks.

    “The repeated problems with the same part of the engine may be indications of a serious design and structural problem with the F135 engine,” said Johan Boeder, a Dutch aerospace expert and editor of the online publication JSF News.

    Pratt & Whitney has already totally redesigned the F135 in an attempt to end its history of frequent failures. But there’s only so much engineers can do. In a controversial move during the early stages of the F-35′s development, the Pentagon decided to fit the plane with one engine instead of two. Sticking with one motor can help keep down the price of a new plane. But in the F-35′s case, the decision proved self-defeating.

    Handout photo of workers on the moving line and forward fuselage assembly areas for the F-35 JSF at Lockheed Martin Corp's factory located in Fort Worth, TexasThat’s because the F-35 is complex — the result of the Air Force, Marines and Navy all adding features to the basic design. In airplane design, such complexity equals weight. The F-35 is extraordinarily heavy for a single-engine plane, weighing as much as 35 tons with a full load of fuel.

    By comparison, the older F-15 fighter weighs 40 tons. But it has two engines. To remain reasonably fast and maneuverable, the F-35′s sole F135 engine must generate no less than 20 tons of thrust — making it history’s most powerful fighter motor.

    All that thrust results in extreme levels of stress on engine components. It’s no surprise, then, that the F-35 frequently suffers engine malfunctions. Even with that 20 tons of thrust, the new radar-dodging plane is still sluggish. The F-35 “is a dog … overweight and underpowered,” according to Winslow Wheeler, director of the Straus Military Reform Project at the Project on Government Oversight in Washington.

    In 2008, two analysts at the RAND Corporation, a California think-tank that works closely with the military, programmed a computer simulation to test out the F-35′s fighting ability in a hypothetical air war with China. The results were startling.

    “The F-35 is double-inferior,” John Stillion and Harold Scott Perdue concluded in their written summary of the war game, later leaked to the press. The new plane “can’t turn, can’t climb, can’t run,” they warned.

    Handout photo of workers on the moving line and forward fuselage assembly areas for the F-35 JSF at Lockheed Martin Corp's factory located in Fort Worth, TexasYet the F-35 is on track to become by far the military’s most numerous warplane. It was designed to replace almost all current fighters in the Air Force and Marine Corps and complement the Navy’s existing F/A-18 jets. The Pentagon plans to acquire roughly 2,400 of the radar-evading F-35s in coming decades, at a cost of more than $400 billion.

    Like it or not, the stealthy F-35 is the future of U.S. air power. There are few alternatives. Lockheed Martin’s engineers have done millions of man-hours of work on the design since development began in the 1990s. Starting work on a new plane now would force the Defense Department to wait a decade or more, during which other countries might pull ahead in jet design. Russia, China and Japan are all working on new stealth fighter models.

    The Pentagon sounds guardedly optimistic about the current F-35 grounding. “Additional inspections of F-35 engines have been ordered,” Rear Admiral John Kirby, a military spokeman said, “and return to flight will be determined based on inspection results and analysis of engineering data.”

    Minor fixes might get America’s future warplane flying again soon — for a while. But fundamental design flaws could vex the F-35 for decades to come, forcing the Pentagon to suspend flying far too often for the majority of its fighter fleet, potentially jeopardizing U.S. national security.
    source:http://blogs.reuters.com/great-debat...limb-cant-run/

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    Last Post: 5th February 2013, 14:43

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