Chengdu J-10

The Chengdu J-10 (歼十, Jiān 10) is a multirole fighter aircraft designed and produced by the People's Republic of China's Chengdu Aircraft Industry Corporation (CAC) for the People's Liberation Army Air Force (PLAAF). Known in the West as the "Vigorous Dragon", the J-10 is designed to be equally useful in both the fighter and light bomber roles and is optimized for all-weather day/night missions.
The J-10 next-generation fighter program remained a top-secret classified project until 2006-12-29, in which the Xinhua News Agency officially disclosed its active duty status in the PLAAF.

History
The program started in 1986, to counter new fourth generation fighters then being introduced by the USSR (namely, the MiG-29 and Su-27). Initially designed as a specialized counter-air fighter, it was later remade into a multirole aircraft capable of both anti-air combat and ground attack missions. However, a Chinese magazine (zh:少年科学画报, ISSN1000-7776) published in June 1979 showed a boy holding a model of J-10. The picture showed that the project began long before 1979.
Although the existence of J-10 has long been reported both inside and outside of China, the Chinese government did not officially admit so until January 2007, when the first photographs of the J-10 were allowed to be published to the public by the Xinhua News Agency. Having been designed under such secrecy, before its official disclosure, many details of the J-10 were subject to much speculation. One version of the J-10 development history is: The first flight of the J-10 took place sometime in 1996, the program suffered a major delay due to a fatal accident which occurred in 1997, and a redesigned prototype flew in 1998, resuming flight testing of the aircraft.[citation needed] (There is evidence, albeit inconclusive, that only one prototype was flying; the other was a ground static testbed. Hence, no crash occurred. [citation needed]) However, the rumored crash has been openly denied by the government of China after the official governmental acknowledgment of the existence of J-10: on 2007-01-15, both the Xinhua News Agency and the PLA Daily have claimed/reported the accomplishments of one of the test pilots of the J-10, Mr. Li Zhonghua (李中华), and, in these reports, one of the accomplishments quoted was that there was not a single crash since the project began. According to Chinese media reports, the first plane, "J-10 01", rolled out in November 1997, and the first flight of "J-10 01" was on 1998-03-23.No incident has been reported.After 18 years in development, the J-10 finally entered service in 2004.The aircraft were first delivered to the 13th test regiment on February 23th of 2003. The aircraft was given the status operational in December of the same year. The first operational regiment was the 131th regiment of the 44th division. It is rumored that a regiment of 3th division also has J-10's.
The most frequently mentioned potential J-10 export customer is the Pakistan Air Force (PAF); in April 2006, the media reported that the Pakistani government intends to procure at least 36 J-10s (with designation of "FC-20" or "FC-10", depending on the report). The "Business Recorder" claims that the Pakistan official document it obtained said the Cabinet "has allowed PAF to set up Joint Working Group (JWG) with CATIC for procurement of 36 FC-20 aircraft". Other media reports cited Pakistan Information Minister Sheikh Rashid in saying the Cabinet has approved the purchase of J-10 from China, in addition to the JF-17. On 2007-03-31, Pakistan Air Force Chief of Air Staff Air Chief Marshal Tanvir Mahmood Ahmed said, "PAF would soon induct fourth and fifth generation high-tech fleet of fighter-bomber aircraft with the aim to modernize the country’s air force which includes the induction of 2 squadrons of Chengdu J-10 aircraft.".The J-10 export deal is estimated to cost $1.5 billion USD total with a flyaway price of $41 million USD for each J-10 fighter with maintenance and parts inclusive.It was reported by Jane's Defence Weekly on 2006-01-09 that a more advanced version of the J-10 is planned, "referred to as the Super-10, with a more powerful engine, thrust-vector control, stronger airframe and passive phased-array radar."

Possible Israeli participation
There are many speculative statements about the Chengdu J-10's relationship with the Israeli IAI Lavi fighter program. In formal (official) Chinese sources, the J-10 is said to have been developed from the canceled Chengdu J-9, which was a canard-configuration fighter program earlier than the Israeli Lavi - a fact that arguably counters the Lavi related speculations. In an interview, the general designer of J-10, Mr. Song Wencong (宋文骢) said, "Our nation's new fighter's external design and aerodynamics configuration are completely made by us and did not receive foreign assistance, this made me very proud and filled with pride. Our nation developed J-9 in the 1960s, this adopted the canard configuration. So, those statements that said J-10 is a copy of Israeli Lavi are just laughable."
However, there are persistent rumors that the J-10 project received Israeli assistance. One news article reported that when the U.S. government questioned Israel's Lavi technology re-exportation to China, the Director General of Israel's Ministry of Defense David Lari "acknowledged in an Associated Press interview that 'some technology on aircraft' been sold to China and that some Israeli companies may not have 'clean hands'".

Design

Engine
The J-10 is a single-seat, delta winged aircraft powered by a single, Russian-built AL-31FN turbofan (maximum static power output of 12,500 kgf (123 kN, 27,600 lbf)) or Chinese-built Woshan WS-10A "Taihang" turbofan (13,200 kgf (129 kN, 29,101 lbf)). However, after the government's official acknowledgment of the existence of the J-10, an interview with J-10 pilots (such as test pilot Mr. Li Cunbao (李存宝)) revealed that a domestic engine is highly unlikely to be equipped in J-10s in the near future. In this interview publicized in January 2007, the pilots claimed that though the domestic Chinese engine could match the performance of the Russian one in every parameter, there was a very serious drawback: the domestic Chinese engine, the WS-10, took much longer to reach the same level of performance as its Russian counterpart. (According to Mr. Li Cunbao's experience, as well as other pilots who flew the J-10 with the WS-10A, it took at least 50% longer, and in many other aspects, almost 100% longer.)[citation needed] Although this only meant one minute difference at most, it was more-than-enough to make a difference between allowing the pilots to safely recover the aircraft by restarting the engine than abandoning the aircraft in a forced ejection. Another problem of the domestic Chinese engine is its lack of FADEC, which is needed for having a same or better aircraft performance when compared with an aircraft with a Russian engine. However, the current WS-10 version available with FADEC is not reliable enough to be accepted into service, and currently all of the matured WS-10s lack FADEC.
As a result of the difficulties faced by WS-10, J-10s are initially powered by Russian AL-31FN engine, and by the mid of the first decade of the 2000s, all 180 AL-31FN engines ordered in two separate batches by China have been delivered. Out of the 180 engines, 100 were built by the Moscow MMPP Salyut plant, and remaining 80 by Ufa-based UMPO, with the price for the first batch was $ 300 million while the price of the second batch was undisclosed. Contrary to many erroneous claims, the AL-31FN is not a thrust vectoring engine, but instead, a derivative of the AL-31F engine used by the Flanker series. The most significant difference between AL-31FN and other models of the AL-31F engines is that due to the limitation of the space available, protruding parts of the engine such as the pump are mounted opposite to that of AL-31F.
During the Paris Airshow in 2001, a prototype of a development of AL-31FN with thrust vectoring to meet Chinese requirement was revealed in public by the Russian engine developer Salyut, with a fully-variable swivel nozzle from the Klimov Design Bureau in St. Petersburg, with developmental cost at least partially funded by China, but the Russian stopped short of identifying which version of J-10 the thrust vectoring engine would be used on. It was revealed that the designation of this thrust vectoring engine is AL-31FN M1, but sources outside China disagree on its application: some claim that it would be used in a new advanced version of the J-10 called the "Super-10", while others claim it would be used on J-10 itself in the upgrades. Furthermore, it was not until the end of 2005 when China finally placed an order of 54 AL-31FN M1 engines at $300 million, but no follow-on orders have been placed since. Various domestic Chinese sources have claimed that the reason for not purchasing anymore AL-31FN M1 engine is that the Mean Time Between Overhaul (MTBO) of the thrust vectoring engine is too short: according to the Russian manufacturer Salyut's claim, thrust vectoring engines of AL-31F series only has a MTBO of 250 hours in comparison more than 1,000 hours of MTBO of the original AL-31F without the thrust vectoring capability, but Chinese sources claimed that in reality, the number is as low as 50 hours MBTO for thrust vectoring engine, the same problem India rumored to have experienced for its Su-30MKIs, but such claims have yet to be confirmed by sources outside China. Adding to the confusion, Chinese government had released the official photo of domestic thrust vectoring engine undergone testing around the same time, but did not provide any other information besides identifying the asymmetric nozzles of thrust vectoring engine in test, neither did China release any information on how reliable the domestic thrust vectoring engine is, such as its MTBO. Some sources outside China have claimed this domestic thrust vectoring engine might be for Shenyang J-11 while other disagreed. Regardless of how they are eventually used, thrust vectoring will undoubtedly boost the J-10's maneuverability. However, if the Chinese criticism on thrust vectoring engines proved to be true, then it is highly unlikely that any thrust vectoring engines would be used on J-10 anytime soon, and the lack of any follow-on orders of AL-31F M1 after the first order only seems to support this view.

Airframe, aerodynamics and flight control
The airframe possesses a large vertical tail, as well as canards placed near the cockpit. The air intake is rectangular in shape, and is located beneath the fuselage. Construction likely incorporates much use of composite materials, as well as more conventional metals. Performance is generally speculated to be within the class of a (Block 40) F-16. A bubble canopy provides 360 degrees of visual coverage for the pilot. The aircraft is designed by the Chengdu Aircraft Design Institute, a subordinate research institute of Chengdu Aircraft Industry Corporation, but in a rather unusual arrangement, the single seat version of the J-10 and the twin seater version of J-10 were designed by two different general designers: the general designer for the single seater version of J-10 was Mr. Song Wencong, while the twin seater version of J-10 was designed by a younger person, the general designer of the JF-17 Thunder Mr. Yang Wei (杨伟). Mr. Yang is the chief designer of the fully digitized fly-by-wire control systems for both versions of J-10. This is disputed by analyst Richard Fisher who credits Israeli consultants for developing the system. For both single seater and twin seater versions, the chief engineer was Mr. Xue Chishou (薛炽寿), who was also the deputy general manager of Chengdu Aircraft Industry Corporation, and the chief test engineer was Mr. Zhou Ziquan (周自全), who was also the deputy director of Chengdu Aircraft Design Institute. Mr. Sang Jianhua (桑建华) of Chengdu Aircraft Design Institute was responsible for the stealth feature designs. China only has three internationally recognized test-pilots who are certified to perform test flights world wide, and all of them are recruited for J-10 program: They were Mr. Lei Qiang (雷強), Mr. Li Cunbao (李存宝) and Mr. Li Zhonghua (李中华). Other test pilots contributed greatly in trials of J-10 included Mr. Xu Yongling (徐勇凌) and Mr. Zou Jianguo (邹建国).

Avionics
A digital, quadruplex fly-by-wire system aids the pilot in flying the aircraft. Information is provided visually to the pilot, in the form of three liquid crystal Multi-Functional Displays (LCD MFDs) within the cockpit. Western-style HOTAS (Hands On Throttle And Stick) controls are incorporated in the J-10's design. A Chinese helmet mounted sight that is claimed to be superior than Russian HMS is also the standard equipment.
The radar type equipping the J-10 is not yet finalized, with a variety of possible candidates, some of which have been installed on the J-10 airframe. With the exception of RP-35, most of the J-10 radars that have been publicized are slotted slotted planar array radars:
Israeli Elta EL/M-2035: The first radar onboard J-10 prototypes for testing purposes. The radar weight 138 kg and Chinese internet sources claimed it is reportedly designated as JL-9, and the radar was mainly used to provide technological know-how for radar/avionics integration for more advanced radars. Such Chinese claims have yet to be confirmed by outside sources.
Chinese/Pakistani JL-10A: Chinese sources have claimed that JL-10A radar on JH-7 has been reportedly installed on the preproduction unit as a stop gap measure as more advanced radars becoming available. Again, such claims have yet to be confirmed by outside sources.
Russian Phazotron Zhemchoug (Pearl): 20 units ordered in the mid-1990, all of which have been delivered. This radar is a derivative of Zhuk (Beetle) radar on Su-27 with newer electronics which reduced the weight by more than a third to 180 kg from the original Zhuk (Beetle) radar. Chinese sources claim that these radars have been installed on the low rate initial production version of J-10. Zhemchoug radar can simultaneously track 20 targets and engage 4 of the 20 tracked via semi-active radar homing air-to-air missiles. However, the radar lacks the same level of air-to-ground capability of its western counterparts. In addition, despite the impressive number of targets it can simultaneously track, the 80/60 km tracking / engagement range is simply considered by Chinese as too short. As a result, no more follow-on orders were placed by Chinese and China had already been seeking other alternatives for later production units of J-10.
Chinese Type 1471 (KLJ-1) radar: many Chinese sources have claimed (to be confirmed) that this radar is the most numerous fire control radars on J-10. Type 1471 is reported to be able to track and engage the same number of targets like the Russian Zhemchoug (Pearl), but with much more improved air-to-ground capability similar to that of west. However, there are other Chinese sources claiming that the maximum number of targets Type 1471 can track is less than 20, but instead, only 15, the same as that of JL-10A.
Italian FIAR Grifo 2000/16: Italian radar offered to Pakistan should Pakistan decided to order J-10. This radar can simultaneously engage 8 targets and like JL-10A, it can simultaneously engage 2 targets out of the total targets tracked with semi-active radar homing air-to-air missiles. The radar is fully compatible and interchangeable with AN/APG-66 at LRU level. The ISO-9002 certified avionics, electronics and radar production facility of the Pakistan Aeronautical Complex at Kamra already has considerable experience in licensed assembly/production of other Italian FIAR radars, namely, Grifo-7, Grifo-Mk-II, and Grifo-MG fire control radars for Pakistani F-7MP/P/PG, and Grifo-2000/16 would have great advantage over its competitors when license assembly/production is included.
Russian Phazotron (NIIR) RP-35: the passive phased array radar designed as a successor to earlier Zhemchoug (Pearl) radar, with full air-to-air and air-to-surface capability. Although western sources reported that Russia is actively marketing this radar to China, neither countries have disclosed any hints on the progress of the deal. Some domestic Chinese internet sources have claimed that the radar is intended for Su-27/J-11 upgrade instead, but such claim has yet to be confirmed.
Russian Tikhomirov (NIIP) Pero: the passive phased array radar originally designed as a successor to N001VEP radar on Chinese Su-30MKK. An unit has been successfully completed evaluation in China by the early 2000, but China did not place any order. In 2007, western sources including Jane's Information Group have claimed (and confirmed by Russians) that China is once again showing the interest in the radar, which might be used for J-10 or its successor. The relative small size of the antenna array of Pero radar (750 mm) in comparison to larger RP-35 makes it easier to integrated into J-10, providing advantages over its competitor. The Pero radar differs from other passive phased array in that it adopts space-feed technology.
In January 2007, scientists/engineers at Chengdu Aircraft Industry Corporation revealed to the public that the current radar of J-10 is slotted planar array with capabilities to simultaneously track 10 targets and engaging 4 of the 10 tracked. However, the scientists/engineers stopped short of revealing the exact designation of the radar, only claimed that development was in progress to arm the aircraft with a passive electronically scanned array airborne radar. It is rumored the passive phased array radar is either Russian or jointly developed with the Russians. (Note: In 2007, many Chinese sources have claimed that the current production version is fitted with either a 147x series or 149x/KLJ-3 series fire control radar from NRIET.)
A comprehensive ECM (Electronic Countermeasures) package is likely to be present, including active jammers such as BM/KG300G self protection jamming pod. Additionally, the KZ900 electronic reconnaissance pod can also be carried. In various defense, aerospace/aeronautical and electronic exhibitions, various helmet-mounted sights developed by domestic Chinese firms have been shown, claimed to have better performance than that of Russia. At various defense and aerospace exhibitions held in Beijing and Zhuhai, J-10 has also been featured in photos and models carrying Blue Sky navigation pod low altitude navigational and attack pod and FILAT Forward-looking Infrared Laser Attack Targeting pod.

Variants
There are currently 2 variants of the Chengdu J-10 fighter:
J-10A: Single seater baseline Multirole model
J-10B1: Twin seater version, for Training, Electronic Warfare (EW), Mini-AWACS and possibly Ground Attack
1: Some analysts mark the twin seater version as J-10S, while others have claimed that J-10S might be the designation of the rumored naval version for carrier deployments, but both claims have yet to be confirmed. The export designation for the twin seater, however, remains F-10B.

Other speculated variants
A possible naval version specialized for aircraft carrier operations
A "stealth" twin-engined variant with thrust-vector control "Super-10"

External loads and armament
The wings provide 11 hardpoints for the attachment of up to 4,500 kg (9,900 lb) of weaponry, fuel tanks, and ECM equipment. Built-in armament consists of a 23 mm cannon, located within the fuselage. External weaponry may include: short-range infrared air-to-air missiles (Chinese PL-8, or the Russian R-73), medium-range radar-guided air-to-air missiles (Chinese PL-11, PL-12, or the Russian R-77), laser-guided and un-guided bombs, anti-ship missiles (Chinese YJ-9K), and anti-radiation missiles (PJ-9).

Lavi

The Lavi (young lion) program began in the late 1970s when IAI agreed to develop a new multi-role fighter to replace Israel's aging A-4 Skyhawk and Kfir combat aircraft. Seeing a need for some 300 planes, including 60 two-seat combat-capable trainers, the Lavi was envisioned primarily as a close air support and tactical attack platform with a secondary air superiority capability. Although Israel was successful in obtaining significant development funds from the United States, nearly all design work was done in Israel. The only major foreign involvement came from Pratt & Whitney, subcontracted to develop the engine, and Grumman, which assisted in the design and manufacture of the composite wing.
The resulting design was largely similar to the American F-16, though slightly smaller and lighter. The Lavi also featured a delta wing and canards with a fly-by-wire control system for superb maneuverability. Furthermore, IAI incorporated an advanced set of avionics systems including glass-cockpit displays, a helmet-mounted targeting system, a heads-up display (HUD), and a multi-mode pulse-Doppler radar. One unique aspect of the design was the decision to develop the two-seater variant first. The space occupied by the backseat was then used for avionics and systems in the single-seat model.
Though the Lavi appeared to be progressing well and two prototypes had completed over 80 flights, political and economic factors began to take their toll on the project. The US had supplied some 40% of the development costs of the new fighter, but refused to allow export licenses for certain pieces of technology. As a result, unit cost began to spiral beyond what the US or Israel had anticipated. In addition, the capabilites of the Lavi were becoming increasingly similar to the F-16, and the US Congress feared the Lavi would interfere with export sales of the American fighter. As a result, Congress withdrew all future funds for Lavi development during the mid-1980s. The Israeli government quickly realized it could not proceed without this support and was forced to cancel the Lavi in August 1987.
Of the five prototypes then completed or under construction, three were sold for scrap and one was given to a museum. However, the third prototype, B-03, was completed using internal IAI funds. This aircraft served as a two-seat technology demonstrator with a complete fit of advanced avionics. The Lavi TD was used for corporate marketing until the mid-1990s when it was converted into a non-flyable ground test vehicle. This marketing effort saw great success in China, and IAI was contracted to provide assistance to Chengdu in developing the very similar J-10 fighter.

Mikoyan Project 1.44

The Mikoyan Project 1.44/1.42 is a Russian Air Force prototype fifth-generation air-superiority fighter aircraft. Apart from a number of names along the lines of "Object/Project 1.44/1.42", the aircraft is also known as the MiG-MFI. It was unofficially known for a time as "MiG-35", although MiG is now using this designation for the export version of the MiG-29OVT. The MFI has also been referred to by some sources as MiG-39. Despite the prototype status of the 1.44/1.42, NATO has assigned the reporting name "Flatpack" to this aircraft. The relationship between the 1.44 and 1.42 designations is unclear outside the military world, and these are generally used interchangeably. For simplicity, the 1.44 designation is used throughout this article.

The 1.44 was Mikoyan-Gurevich design bureau's entry to Russia's Многофункциональный Фронтовой Истребитель (Mnogofounksionalni Frontovoi Istrebitel - Multifunctional Frontline Fighter) program (a development program that originated in the 1980s, similar to the Advanced Tactical Fighter program held in the United States). It was designed to compete with the American Lockheed Martin F-22 Raptor. Many of its design features are similar to those found on fifth generation Western fighters, including thrust vectoring, supersonic cruise and modern avionics. Looking back upon its development history, the 1.44 served purely as a technological showcase and testbed for future aircraft designs, not as an actual air superiority fighter.

The MiG 1.44/1.42 has been shrouded in mystery throughout the course of its existence. The Russian government cancelled the MFI program in 1997 due to the unacceptably high per-unit cost of the aircraft (Ф2.05 billion RUR, US$70 million). Development continued, with the first test flight taking place on February 29, 2000 and two confirmed test flights in 2001. In Russia's abandonment of the MFI program, the PAK FA (Перспективный Авиационный Комплекс Фронтовой Авиации - Perspektivnyi Aviatsionnyi Kompleks Frontovoi Aviatsyi - Prospective Air Complex for Tactical Air Forces) program was initiated for the development of an aircraft designed to fill a role similar to that of the F-22, and come at a size and cost similar to that of the F-35 Lightning II.
In 2001, India agreed with Russia to make the PAK FA program a development/production joint-venture between the two nations. Both Mikoyan-Gurevich and Sukhoi submitted concepts to the Defense Ministry for the PAK FA program (MiG entering an updated Project 1.44), but the Russian Defense Ministry selected the Sukhoi Design Bureau as the primary contractor for the PAK FA fighter. Design work has commenced on a backward-swept winged derivative of Sukhoi's experimental Su-47 Berkut aircraft. PAK FA proves to be a very ambitious program, with production of the PAK FA fighter planned to commence in 2010. MiG-MAPO and Yakovlev have also been mentioned as secondary contractors. The MiG 1.44 is currently serving as a technology demonstrator for the PAK FA program. The in-development PAK FA aircraft will use the same in-development Lyulka AL-41F engine planned for the 1.44.

The 1.44 is a delta-winged, twin-tailed single seat air superiority/strike fighter with an all-moving forward canard plane. Its physical appearance and design characteristics mostly resemble the Eurofighter Typhoon.
It is powered by two Lyulka AL-41F afterburning, thrust vectored turbofan jet engines, each generating 175 kN (39,340 lbf) of thrust (these engines are still in development). Both engines are fed by a single air intake placed under the fuselage. The 35-ton aircraft has a theoretical at-altitude maximum speed of Mach 2.6, and is capable of long-term supersonic flight. The 1.44 has a tricycle landing gear system, with a single, dual-wheel landing gear in the front, and two single-wheels in the rear.
Avionics on the 1.44 are considered cutting-edge by Western standards: the glass-cockpit-enabled fighter features a pulse Doppler radar with a passive electronically scanned array antenna. The radar system is linked to a fire control system that allows the fighter to engage up to twenty separate targets at the same time. It is claimed that the radar system also enables the 1.44 to compete with the likes of the F-22 at beyond visual range (BVR) aerial combat.
The handling and manoeuvrability characteristics of the 1.44 are estimated to be superior to that of the F-22, since the MiG features 3D thrust vectoring, digital fly-by-wire flight control, and two powerful engines. Its internal bay is large enough to carry 8 R-77 missiles.

Lockheed Martin F-35 Lightning II

US Air Force Chief of Staff Gen. T. Michael Moseley officially naming the F-35 as the Lighting II
Comparison of F-35 models

The F-35 was declared winner of the US Department of Defense Joint Strike Fighter (JSF) competition in 2001 when the Lockheed Martin X-35 was judged superior to the Boeing X-32. The goal of the F-35 is to provide a family of three distinct variants of a multi-role fighter that use a 70% to 90% common airframe to reduce production and maintenance costs. The JSF is a joint program between the United States and United Kingdom, and several other international partners are also participating in the development effort. The primary customers dictating the design specifications for the various F-35 models are the US Air Force, US Navy, US Marine Corps, UK Royal Air Force, and UK Royal Navy. The overall design developed by Lockheed with partners Northrop Grumman and BAE Systems resembles a scaled-down F-22, but each F-35 variant is tailored to the specific needs of its operators.
The simplest and least expensive model is the F-35A conventional takeoff and landing (CTOL) version based on the X-35A. Intended primarily for the US Air Force, the F-35A is also likely to be purchased by a number of export customers. Italy and the Netherlands are Level II partners while Level III partners include Australia, Canada, Denmark, Norway, and Turkey. Both Singapore and Israel are also foreign military sales participants. The F-35 CTOL variant will be optimized for attack duties with a limited air-to-air capability to complement the F-15 and F-22.
The US Navy needs much the same capabilites in its F-35C carrier variant (CV) model based on the X-35C. This model is intended to complement the F-18E/F and give the Navy its first dedicated stealth attack aircraft. However, the F-35 CV is modified to meet more stringent range and landing requirements. The most obvious of these modifications is a 35% larger wing permitting a higher fuel capacity and providing greater wing area for improved lift at low speeds. Other changes to the F-35 CV version include larger fin and elevator surfaces, ailerons in addition to flaperons on the wing, enlarged control surfaces, a modified control system, strengthened landing gear, a catapult launch bar on the twin-wheel nose gear, an arrester hook, and a wing folding mechanism.
Perhaps the most critically needed F-35 variant is the most complex, the F-35B short/vertical takeoff and landing (STOVL) model based on the X-35B. This model is intended to replace the aging AV-8B and GR.5/7 Harrier II as well as the Harrier and Sea Harrier operated by the US Marines, Royal Air Force, and Royal Navy. The F-35B variant features a ducted lift fan located in an enlarged spine just aft of the cockpit. This fan takes the place of a fuel tank carried aboard the other F-35 models and is used to provide most of the lift needed for vertical flight. The main engine powers the lift fan and is also equipped with a unique swivelling nozzle that can redirect thrust aft for level flight or down for vertical flight.
Unfortunately, the complexity of the F-35 STOVL model has also caused significant development problems for the JSF program. The early design of the F-35B proved to be significantly overweight, and the program was delayed by over a year as engineers struggled to meet the ambitious performance and cost goals. The solution ultimately adopted was to reduce the size of the internal weapon bays in comparison to the other F-35 models. While the CTOL and CV variants can carry 2,000-lb weapons internally, the largest weapon the F-35B can carry in its weapon bays is the 1,000-lb GBU-32 JDAM. The vertical tails of the F-35 STOVL have also been shortened to reduce weight.
Design of the JSF has placed the greatest emphasis on advanced weapons concepts and affordability. One of the most sophisticated features common to the various F-35 models is an integrated core processor that fuses information from all the aircraft's sensors into a single, coordinated view of the battlefield. Among these sensors is an active electronically scanned array (AESA) radar with a synthetic aperture radar mapping mode to provide the pilot with far more precise search and targeting capabilites than exist in today's attack fighters. The F-35 is also equipped with an infrared search and track (IRST) system for air-to-air combat while advanced air-to-ground combat features include an electro-optical targeting system (EOTS) with a forward-looking infrared (FLIR) imager, a targeting laser, a laser spot tracker, and a CCD TV camera. The F-35's sophisticated software is capable of analyzing the information these sensors provide using an automatic target recognition and classification (ATRC) system to identify specific targets. While stealth is also emphasized through the use of internal weapon bays and low obervable shaping techniques, sacrifices have been made to lower costs and ease maintenance. As a result, the F-35 is not as stealthy as the F-22 or B-2.
During the current system development and demonstration phase of the program, 14 F-35 aircraft are to be built to perform flight tests leading up to initial production. These F-35 test aircraft include five CTOL, four CV, and five STOVL models. An additional eight ground test articles will also be built for static testing, drop testing, and radar signature evaluation. Low-rate initial production is due to begin in 2008.
F-35 orders remain a matter of debate, but current plans call for the US and UK to purchase approximately 2,600 aircraft. The US Air Force originally planned for 2,036 F-35A aircraft but reduced its requirement to 1,763 in 1997. This total remains the offical requirement though the Air Force has unofficially indicated its order will be reduced to between 1,000 and 1,300 aircraft. Some number of these may also be F-35B models as the Air Force has expressed a requirement for up to 250 STOVL aircraft for close air support missions. Such a purchase would likely assist in reducing unit cost and improving the stability of the STOVL program, which has often been targeted for possible cancellation.
The US Navy and Marine Corps have also begun combining their combat aircraft wings in part to reduce the need for new aircraft. The Marines originally requested 642 F-35B models while the Navy wanted 300 F-35C variants. In 1997, these figures were refined to 609 for the Marines and 480 for the Navy for a total of 1,089 F-35 aircraft. As of 2004, that total had been reduced to 680 aircraft including 350 F-35B variants and 330 F-35C models. The services have yet to determine how those aircraft will be allocated since the Marines may recieve a mixture of both CV and STOVL aircraft. Likewise, the Royal Navy may split its order between the F-35 STOVL and F-35 CV models since the F-35C models could potentially be operated aboard the UK's large aircraft carriers due to enter service in the 2010s. The total UK order has shrunk from 150 to 138 aircraft.
In addition to US and UK orders, the potential exists for over 2,000 F-35 sales to export customers. The international partners currently involved in the program have so far expressed tentative plans for nearly 600 aircraft. Italy is interested in up to 131 planes, Australia and Turkey are considering 100 each, the Netherlands 85, Canada 60, and Denmark and Norway may buy 48 apiece. None of these countries have officially placed orders so far, but the F-35 program is encouraging international partners to commit to firm orders as soon as possible. Convincing the partners to do so may prove difficult, however, given past development delays that have driven up costs and pushed service entry back from 2011 to 2013. These delays may cause international partners to instead order competing aircraft like the Gripen or Eurofighter Typhoon that are already in production. Norway has already threatened to pull out of the program over workshare concerns, and Israel's involvement was suspended for several months in retaliation for possible technology transfer to China. Regardless, export sales are expected to be strong and F-35 production will likely last until at least 2030.

X-32 Joint Strike Fighter (JSF)

The Joint Strike Fighter (JSF) is a multi-role fighter optimized for the air-to-ground role, designed to affordably meet the needs of the Air Force, Navy, Marine Corps and allies, with improved survivability, precision engagement capability, the mobility necessary for future joint operations and the reduced life cycle costs associated with tomorrow’s fiscal environment. JSF will benefit from many of the same technologies developed for F-22 and will capitalize on commonality and modularity to maximize affordability.
The 1993 Bottom-Up Review (BUR) determined that a separate tactical aviation modernization program by each Service was not affordable and canceled the Multi-Role Fighter (MRF) and Advanced Strike Aircraft (A/F-X) program. Acknowledging the need for the capability these canceled programs were to provide, the BUR initiated the Joint Advanced Strike Technology (JAST) effort to create the building blocks for affordable development of the next-generation strike weapons system. After a review of the program in August 1995, DoD dropped the "T" in the JAST program and the JSF program has emerged from the JAST effort. Fiscal Year 1995 legislation merged the Defense Advanced Research Projects Agency (DARPA) Advanced Short Take-off and Vertical Landing (ASTOVL) program with the JSF Program. This action drew the United Kingdom (UK) Royal Navy into the program, extending a collaboration begun under the DARPA ASTOVL program.
The JSF program will demonstrate two competing weapon system concepts for a tri-service family of aircraft to affordably meet these service needs:
USAF-Multi-role aircraft (primarily air-to-ground) to replace F-16 and A-10 and to complement F-22. The Air Force JSF variant poses the smallest relative engineering challenge. The aircraft has no hover criteria to satisfy, and the characteristics and handling qualities associated with carrier operations do not come into play. As the biggest customer for the JSF, the service will not accept a multirole F-16 fighter replacement that doesn't significantly improve on the original.
USN-Multi-role, stealthy strike fighter to complement F/A-18E/F. Carrier operations account for most of the differences between the Navy version and the other JSF variants. The aircraft has larger wing and tail control surfaces to better manage low-speed approaches. The internal structure of the Navy variant is strengthened up to handle the loads associated with catapult launches and arrested landings. The aircraft has a carrier-suitable tailhook. Its landing gear has a longer stroke and higher load capacity. The aircraft has almost twice the range of an F-18C on internal fuel. The design is also optimized for survivability.
USMC-Multi-role Short Take-Off & Vertical Landing (STOVL) strike fighter to replace AV-8B and F/A-18A/C/D. The Marine variant distinguishes itself from the other variants with its short takeoff/vertical landing capability.
UK-STOVL (supersonic) aircraft to replace the Sea Harrier. Britain's Royal Navy JSF will be very similar to the U.S. Marine variant.
The JSF concept is building these three highly common variants on the same production line using flexible manufacturing technology. Cost benefits result from using a flexible manufacturing approach and common subsystems to gain economies of scale. Cost commonality is projected in the range of 70-90 percent; parts commonality will be lower, but emphasis is on commonality in the higher-priced parts.
The Lockheed Martin X-35 concept for the Marine and Royal Navy variant of the aircraft uses a shaft-driven lift-fan system to achieve Short-Takeoff/Vertical Landing (STOVL) capability. The aircraft will be configured with a Rolls-Royce/Allison shaft-driven lift-fan, roll ducts and a three-bearing swivel main engine nozzle, all coupled to a modified Pratt & Whitney F119 engine that powers all three variants.
The Boeing X-32 JSF short takeoff and vertical landing (STOVL) variant for the U.S. Marine Corps and U.K. Royal Navy employs a direct lift system for short takeoffs and vertical landings with uncompromised up-and-away performance.
Key design goals of the JSF system include:
Survivability: radio frequency/infrared signature reduction and on-board countermeasures to survive in the future battlefield--leveraging off F-22 air superiority mission support
Lethality: integration of on- and off-board sensors to enhance delivery of current and future precision weapons
Supportability: reduced logistics footprint and increased sortie generation rate to provide more combat power earlier in theater
Affordability: focus on reducing cost of developing, procuring and owning JSF to provide adequate force structure
JSF’s integrated avionics and stealth are intended to allow it to penetrate surface-to-air missile defenses to destroy targets, when enabled by the F-22’s air dominance. The JSF is designed to complement a force structure that includes other stealthy and non-stealthy fighters, bombers, and reconnaissance / surveillance assets.
JSF requirements definition efforts are based on the principles of Cost as an Independent Variable: Early interaction between the warfighter and developer ensures cost / performance trades are made early, when they can most influence weapon system cost. The Joint Requirements Oversight Council has endorsed this approach.
The JSF’s approved acquisition strategy provides for the introduction of an alternate engine during Lot 5 of the production phase, the first high rate production lot. OSD is considering several alternative implementation plans which would accelerate this baseline effort.
Program Status
The focus of the program is producing effectiveness at an affordable price—the Air Force’s unit flyaway cost objective is $28 million (FY94$). This unit recurring flyaway cost is down from a projected, business as usual,cost of $36 million. The Concept Demonstration Phase (CDP) was initiated in November 1996 with the selection of Boeing and Lockheed Martin. Both contractors are: (1) designing and building their concept demonstration aircraft, (2) performing unique ground demonstrations, (3) developing their weapon systems concepts. First operational aircraft delivery is planned for FY08.
The JSF is a joint program with shared acquisition executive responsibilities. The Air Force and Navy each provide approximately equal shares of annual funding, while the United Kingdom is a collaborative partner, contributing $200 million to the CDP. CDP, also known as the Program Definition and Risk Reduction (PDRR) phase, consists of three parallel efforts leading to Milestone II and an Engineering and Manufacturing Development (EMD) start in FY01:
Concept Demonstration Program. The two CDP contracts were competitively awarded to Boeing and Lockheed Martin for ground and flight demonstrations at a cost of $2.2 billion for the 51-month effort, including an additional contract to Pratt & Whitney for the engine. Each CDP contractor will build concept demonstrator aircraft (designated X-32/35). Each contractor will demonstrate commonality and modularity, short take-off and vertical landing, hover and transition, and low-speed carrier approach handling qualities of their aircraft.
Technology Maturation. These efforts evolve key technologies to lower risk for EMD entry. Parallel technology maturation demonstrations are also an integral part of the CDP / PDRR objective of meeting warfighting needs at an affordable cost. Focus is on seven critical areas: avionics, flight systems, manufacturing and producibility, propulsion, structures and materials, supportability, and weapons. Demonstration plans are coordinated with the prime weapon system contractors and results are made available to all program industry participants.
Requirements Definition. This effort leads to Joint Operational Requirements Document completion in FY00; cost/performance trades are key to the process.

McDonnell Douglas X-36 Tailless Agility Research Aircraft

Forward view of an X-36 illustrating the engine inlets and chined nose
Overhead view showing the X-36 planform shape

X-36 during high-speed taxi tests

Aircraft designers have been exploring planes without horizontal or vertical tail control surfaces for many decades. Such a plane would be simpler and potentially less expensive to build, more maneuverable, lighter, create less drag, and possess greater stealth characteristics. However, previous attempts suffered from excessive control instabilities that were not solvable with technology available at the time. That limitation has changed with the development of computerized fly-by-wire control systems able to deflect control surfaces far faster than a human pilot can. This technology makes it possible to control very unstable configurations.
To further research the feasilbility of applying tailless technology to future stealthy and agile fighters, NASA contracted McDonnell Douglas to build two unmanned 28% scale research vehicles based on a potential fighter concept previously developed in a company design study. The resulting prototypes, designated the X-36, had no vertical or horizontal tail surfaces. The X-36 was instead maneuvered using canards, split ailerons, and a thrust-vectoring nozzle. The X-36 was flown remotely by transmitting data from an onboard video camera and microphone to a pilot-in-the-loop ground station equipped with a "virtual cockpit." The cockpit featured a heads-up-display and a moving-map display giving the pilot a complete picture of the aircraft's state.
The original X-36 flight test program began in May 1997 and lasted 25 weeks. This period included 31 flights that focused primarily on the design's low-speed high-angle-of-attack performance. The X-36 reached altitudes of over 20,000 ft (6,100 m), speeds in excess of 230 mph (370 km/h), and angles of attack up to 40° in a total of 15 hr and 38 min of flight.
Although the program evaluated four different sets of flight control software, an additional two flights were funded by the Air Force Research Laboratory (AFRL) to evaluate the Reconfigurable Control for Tailless Fighter Aircraft (RESTORE) software. These final flights, conducted in December 1998, demonstrated the adaptability of the neural-net algorithm to compensate for in-flight damage to control surfaces such as flaps, ailerons, and rudders.
With the flight test program completed, both X-36 airframes were placed in flyable storage condition in a hangar at NASA Dryden in California. The two were maintained for possible use in future research efforts such as testing a highly advanced reconfigurable flight control system. The only X-36 that flew during the flight testing programs has since been donated by Boeing and placed on display at the National Museum of the US Air Force in Ohio.