The Legendary Dragon
The J-20 Mighty Dragon
Welcome back to Brooke In The Air! Today we’re doing a deep dive into the pride of China's People's Liberation Army Air Force (PLAAF), the Chengdu J-20 Mighty Dragon!
OVERVIEW/INTRODUCTION
The Chengdu J-20 (Chinese: 歼-20; pinyin: Jiān-Èrlíng), also known as Mighty Dragon (pinyin: Wēilóng, NATO reporting name: Fagin), is a twin-engine all-weather stealth fighter developed by China's Chengdu Aerospace Corporation for the People's Liberation Army Air Force (PLAAF).
The J-20 is designed as an air superiority fighter with precision strike capability. The aircraft has three notable variants: the initial production model, the revised airframe variant with new engines and thrust-vectoring control, and the aircraft-teaming capable twin-seat variant.
HISTORY
Descending from the J-XX program of the 1990s, the aircraft made its maiden flight on 11 January 2011, and was officially revealed at the 2016 China International Aviation & Aerospace Exhibition. The aircraft entered service in March 2017 with the first J-20 combat unit formed in February of 2018, making China the second country in the world and the first in Asia to field an operational stealth aircraft.
J-20 during flight demonstrations
The J-20 emerged from the late-1990s J-XX program. In 2008, the PLAAF endorsed Chengdu Aerospace Corporation's proposal, Project 718. Chengdu had previously used the double-canard configuration in the J-9, its first design and cancelled in the 1970s, and the J-10.
In 2009, a senior PLAAF official revealed that the first flight was expected in 2010–11, with a service entry date by 2019. On 22 December 2010, the first J-20 prototype underwent high speed taxiing tests outside the Chengdu Aircraft Design Institute (CADI).
Three months later, the first J-20 prototype made its maiden flight in Chengdu. The first prototype was painted with the number "2001".
In May 2012, the second prototype took flight in the CADI facility.
Several changes were made to the third J-20 prototype, numbered "2011", which made its maiden flight in March of 2014. The new prototype showed increasing sophistication in design, including numerous subtle changes from the first two prototypes.
The new airframe introduced modified diverterless supersonic inlet (DSI) intakes, stealth coating, streamlined underwing fairings, and redesigned vertical stabilizers.
Analysts noted new equipment and devices for multi-role operations, such as integrated targeting pods for precision-guided munition, and six additional passive infrared sensors can also be spotted around the aircraft.
In December of 2015, the low rate initial production (LRIP) version of the J-20 was spotted by military observers. The LRIP aircraft revealed dielectric surfaces that were previously painted for prototypes, potentially containing various sensors or baked-in radar absorbing materials.
In October of 2017, Chinese state media reported that the designs of the J-20 had been finalized, and were ready for mass production as well as being combat-ready.
In March of 2018, Chinese military revealed other versions of the J-20 platform were being developed.
In January ofv2019, Chinese media reported that a twin-seat variant of the J-20 is rumored to be in development for use in tactical bombing, electronic warfare and carrier strike roles.
In November of 2019, a J-20 painted in yellow primer-coating was spotted during its flight testing by defense observers at the Chengdu Aerospace Corporation manufacturing facility. The aircraft is equipped with a new variant of WS-10 Taihang engines with serrated afterburner nozzles to enhance stealth. Report indicated Chengdu Aerospace Corporation terminated the manufacturing of J-20 with Russian engines in mid-2019.
Chinese media reported that a new variant of the J-20 was unveiled on July 8, 2020, and entered mass production the same day. The only change mentioned was that the new J-20 was to be equipped with thrust vectoring control. Conflicting reports emerged regarding the exact engine type.
Analyst Andreas Rupprecht expressed skepticism regarding the use of Russian engines on the J-20, as he believes that the J-20 is using a variant of the WS-10, which he called the WS-10C. This engine has improved thrust, stealthier serrated afterburner nozzles, and higher reliability, but it is not designed for thrust vectoring, unlike the WS-10 TVC demonstrated on a J-10 in 2018 China International Aviation & Aerospace Exhibition. Analyst Jamie Hunter believed the new engine type is what he called WS-10B-3, a Chinese-made thrust-vectoring engine demonstrated at the 2018 Zhuhai Airshow.
In January of 2021, South China Morning Post reported that the J-20 would replace its engines with the WS-10C. The WS-10C is considered an interim solution before Shenyang WS-15 passes evaluations. Moreover, WS-10C will not be equipped with the thrust-vectoring version of the J-20 that entered mass production in late 2019, which still required further testing.
Overall, Chinese engineers believe WS-10C is comparable with AL-31F engines in performance, and the replacement would also reduce China's dependency on Russian engines. The WS-10C-powered J-20 was officially showcased to the public on 28th of September, 2021 at the Zhuhai Airshow.
The development of a twin-seater variant was hinted at by J-20's chief designer in 2019. In January 2021, Aviation Industry Corporation of China released computer renderings of the twin-seat variant of the J-20 fighter in celebration of the 10th anniversary of the jet's maiden flight. In February 2021, a South China Morning Post infographic depicted a twin-seat J-20 variant powered by thrust vectoring WS-10C.
In October of 2021, a taxiing prototype, dubbed J-20S by analysts, was spotted near Chengdu Aerospace Corporation (CAC) facilities, making J-20S the first-ever two-seat stealth fighter. The twin-seat design allows the possibility for the second operator to coordinate attacks and reconnaissance missions from other friendly aircraft via networking or unmanned combat aerial vehicles (UCAVs) linked via "loyal wingman" systems and sensors.
The advantage of a second operator includes the potential for better interpreting and exploiting the enormous sensory data that could overload the limited cognitive and processing capacity for a single human, especially in a contested air combat environment.
In March of 2022, Chinese state media reported that the J-20, reportedly with one engine replaced by the WS-15, had performed flight trials. In December 2022, Chinese military analysts indicated the WS-15 was undertaking the last stage of testing and development.
In late December, a prototype of the new J-20 variant was observed at Chengdu Aerospace Corporation (CAC) facilities as mentioned. The new variant was painted in yellow primer and different from previous J-20 aircraft in airframe design, with a low-profile blended canopy, aiming to optimize transonic flight performance and maneuverability. The new prototype was speculated to be used to test the WS-15 engine and thrust-vectoring. In March 2023, the executive of Aero Engine Corporation of China (AECC) announced the serial production of the WS-15 has started. FlightGlobal speculated that small-scale production and in-flight testing with the J-20 fighter was underway.
In October of 2023, the Pentagon reported that PLAAF was upgrading the J-20, with enhancements such as extended weapon-carrying capability, thrust vectoring nozzles, control systems for unmanned aircraft teaming, and WS-15 high-thrust engines.
In November of 2024, the Aviation Industry Corporation of China (AVIC) officially announced the twin-seat variant of the J-20, designated the J-20S. Functions of the variant include long-range operations with multi-role capabilities, including air superiority, precision strikes, manned-unmanned teaming, battlefield surveillance, electronic warfare, and command and control.
DESIGN SPECS
The J-20 has a long and blended fuselage, with a chiseled nose section and a frameless canopy. Immediately behind the cockpit are low-observable diverterless supersonic inlet (DSI) intakes. All-moving canard surfaces with pronounced dihedrals are placed behind the intakes, followed by leading edge extensions (LERX) merging into the delta wing with forward-swept trailing edges. The aft section has twin outward canted all-moving fins, short but deep ventral strakes, and conventional or low-observable engine exhausts.
Initial J-20 Schematics
One important design criterion for the J-20 is high instability. This requires sustained pitch authority at a high angle of attack, in which a conventional tail-plane would lose effectiveness due to stalling. On the other hand, a canard can deflect opposite to the angle of attack, avoiding stall and thereby maintaining control. A canard design is also known to provide good supersonic performance, excellent supersonic and transonic turn performance, and improved short-field landing performance compared to the conventional delta-wing design.
The use of a bubble canopy, extensive flight-control surfaces, and canard configuration for angle-of-attack control indicates J-20's intention to operate in air-superiority missions and within-visual-range engagements. Chief test pilot Li Gang describes the J-20 as having comparable manoeuvrability to the Chengdu J-10 while being significantly better at low-observable (LO) performance. The J-20 is a multirole air superiority fighter, with the interceptor role being just one of the options.
The J-20 avionics aim to obtain situational awareness through advanced sensor and data fusion while denying situational awareness to the adversary through stealth and electronic warfare.
The J-20 features an integrated avionic suite consisting of multi-spectral sensors capable of providing omnidirectional coverage with. Official information on the type of radar that J-20s use has not yet been released publicly. Some analysts believed that J-20s used Type 1475 (KLJ-5) active electronically scanned array (AESA) radar with 1856 transmit/receive modules, but more recent information revealed that this radar was designed for upgraded versions of the J-11D.
Other analysts point out that, based on the nose cross-section of the J-20 and known data about a single transmit/receive module surface in the J-16's AESA radar system, J-20s likely contain 2000–2200 transmit/receive modules.
A Chinese study commissioned by the military suggested the J-20's AESA radar would have a tracking range of 200 km (120 mi; 110 nmi) with simultaneous tracking for 20 targets, and multi-target engagement capabilities.
The nose includes electro-optical sensors for an omnidirectional view, including a chin-mounted enclosed electro-optical sensor with a forward field-of-view for air-to-air applications.
In 2015, Beijing A-Star Science and Technology was developing passive sensors, the EOTS-89 electro-optical targeting system and the EORD-31 infrared search and track, for the J-20. The passive sensors enhance the capability to engage stealthy aircraft. The J-20's usage of electro-optical sensors resembles the Lockheed-Martin F-35 Lightning II's avionic suite, including the AN/AAQ-37 Distributed Aperture System.
According to Chinese media in February 2024, the J-20 is equipped to perform airborne early warning and control (AEW&C, known to the west as AWACs) operations.
The aircraft features a fully-digital glass cockpit with one primary large color liquid-crystal display (LCD) touchscreen, three smaller auxiliary displays, and a wide-angle holographic heads-up display (HUD). The size of the primary LCD screen is 610 mm × 230 mm (24 in × 9 in), 650 mm (25.63 in) diagonal size, with two illumination systems for operational redundancy. The aircraft is fitted with a helmet-mounted display (HMD) system, which displays combat information inside the pilots' helmet visor and facilities firing missiles at high off-boresight angle.
ARMAMENT
J-20 featuring its internal weapons bays and 4 PL-15 missiles
The main weapon bay is capable of housing both long-range air-to-air missiles (AAM; PL-15 – PL-21) and precision-guided munitions (PGM; LS-6/50, LS-6/100, FT-7), while the two smaller lateral weapon bays behind the air inlets are intended for short-range AAMs (PL-10). These side bays allow closure of the bay doors prior to firing the missile, enhancing stealth and allowing the missile to be fired in the shortest possible time.
The main bay may carry four medium/long-range AAMs, with each lateral bay carrying a short-range missile. In 2023, the United States reported that China planned to increase the J-20's missile capacity in "low-observable configuration". A staggered arrangement of six PL-15s is possible with modified rail launchers under development.
A thinner profile missile, designated PL-16, was also reportedly under development in 2020 to allow the six missiles for internal carriage. The PL-16 features a compressed airframe, folded fins, and a high-performance dual-pulse motor to reduce size, while maintaining the same level of performance as the PL-15. The J-20 will likely use air-to-air missiles to engage in air superiority combat with other aircraft and to destroy high-value airborne assets. Supplemental missions may include launching anti-radiation missiles and air-to-ground munitions for precision-strike missions.
The wings include four hardpoints for auxiliary fuel tanks to extend the ferrying range and large weapons, like the PL-17.
The ‘Dragon is unlikely to be the primary carrier of such large weapons as they compromise the aircraft's stealth.
The J-20 reportedly lacks an internal autocannon or rotary cannon, strongly suggesting a preference for long-range engagements with missiles rather than short-ranged dogfights.
ENGINES
The Mighty Dragon is powered by Shenyang WS-10 turbofan engines, an afterburner turbofan engine manufactured by Shenyang Liming Aircraft Engine Company (SLAEC), which reportedly enables supercruise and high maneuverability. The WS-10C served as an interim engine before the adoption of the more powerful Shenyang WS-15.
During the prototype and initial service period, the fighter was powered by an improved Lyulka-Saturn AL-31 variant, reportedly the AL-31FM2 developed by Salyut. The engine has a "special power setting" thrust of 145 kN (32,600 lbf).The Shenyang WS-10C was selected as the replacement for AL-31 due to delays on the testing and production of the WS-15 engine. Aircraft powered by WS-10Cs were flying by September of 2019.
The engine has a thrust of 142-147 kN, a thrust-to-weight ratio of 9.5, providing necessary propulsion for J-20 to supercruise, and is fitted with serrated afterburner nozzles for enhanced rear-aspect stealth.
Flights with prototypes powered by the WS-10C were underway by November 2020. The PLAAF began receiving WS-10C powered aircraft by 2021. In January 2022, it was reported that aircraft powered by the WS-10C would be upgraded with TVC. Reportedly, the WS-10C enabled supercruise.
The intended powerplant is the Shenyang WS-15 with a thrust of 180 kN. The WS-15 enables supercruise, enhances maneuverability, and gives the J-20 more thrust than the F-22 and F-35. The engine's extra power and cooling could also be used by future directed energy weapons and sensors.
The WS-15 development was reportedly ongoing in 2019. In March 2022, Chinese state media reported that the J-20 had performed flight trials with the engine and experienced significantly improved performance.
It was also reported that eventually, new production and existing aircraft powered by the AL-31 would be fitted with the WS-15. In April 2023, China reported that the WS-15 was ready for mass production.
J-20 showing off dorsal stealth aspects
The aircraft is equipped with a retractable refueling probe embedded on the right side of the cockpit, to help the fighter to maintain stealth while flying greater distances with a need to refuel.
STEALTH ASPECTS
Analysts noted that the J-20's airframe employs a holistic approach to reduce its Radar cross-section (RCS), uniquely combining canard wings with leading edge root extensions (LERX). The chined forebody, modified radar radome, and electroconductive canopy use a stealth shaping, yielding signature performance in a mature design similar to the F-22.
The diverterless supersonic inlets (DSI) leading into serpentine inlets (S-ducts) can obscure the reflective surface of the engine from radar detection. DSI intakes save weight, reduce complexity, and minimize radar signature.
Additional low-observable features include a flat fuselage bottom holding an internal weapons bay, sawtooth edges on compartment doors, mesh coverings on cooling ports at the base of the vertical tails, embedded antennas, and radar-absorbent coating materials.
While the aircraft's fins/strakes and axisymmetric rear areas may expose the aircraft to radar, the overall stealth shaping of the J-20 is robust and considerably more capable than the Russian PAK-FA. Improvements regarding stealth were subsequently introduced - one prototype in 2014 was powered by WS-10 engines equipped with different jagged-edge nozzles and tiles for greater stealth.
The J-20 production model with the serrated WS-10C engine is also capable of mitigating negative effects on rear-aspect stealth.
OPPOSITION
Others have raised doubts about the use of canards on a low-observable design, stating that canards would guarantee radar detection and compromise stealth. However, these critiques with respect to the canard's RCS may be unfounded. Canards and low-observability are not necessarily mutually exclusive designs.
Northrop-Grumman's proposal for the U.S. Navy's Advanced Tactical Fighter (ATF) incorporated canards on a stealthy airframe. Lockheed Martin employed canards on a stealth airframe for the Joint Advanced Strike Technology (JAST) program during early development before dropping them due to complications with aircraft carrier recovery. McDonnell-Douglas (now Boeing) and NASA's X-36 featured canards and was considered to be extremely stealthy.
RCS can be further reduced by controlling canard deflection through flight-control software, as on the Eurofighter. Similarly, Chinese aerospace researchers also concluded that, in terms of stealth, the canard delta configuration is comparable with the conventional arrangement.
In May of 2018, Indian Air Chief Marshal B.S. Dhanoa claimed at a press conference that the radars on India's Sukhoi Su-30MKI fighters were "good enough" and could detect a J-20 from "several kilometers away" while answering a question on whether the J-20 posed a threat to India. However, experienced analysts didn't take Dhanoa's claim seriously due to his exaggeration and the lack of validity.
Analyst Justin Bronk from Royal United Services Institute noted that Chinese were possibly flying the J-20 with radar reflectors during peacetime for safety and training purposes due to the potential for accidents and identification from other aircraft or ground installations.
In a more recent report, Bronk also states that even with limited stealth, J-20 could hide and strike enemy critical platforms in an airspace with background clutter caused by non-stealth fighters and other electromagnetic noise.
According to Aviation Week in 2021, the J-20's stealth characteristics were superior to the Sukhoi Su-57 in the frontal aspect but inferior overall - particularly in the rear - to the F-35 . As the program matures with each batch, recently produced models have seen constant and significant enhancement in their stealth profile.
TESTING
On the 13th of September in 2015, a new prototype, marked "2016", began testing. It had noticeable improvements, such as apparently modified DSI bumps on the intakes. The DSI changes suggested the possibility of more powerful engines being used than its predecessors, likely to be an advanced 14-ton thrust derivative of the Russian AL-31 or Chinese Shenyang WS-10 turbofan engines.
By 2020, the J-20 was scheduled to use the 18–19 ton WS-15 engine, enabling the jet to supercruise without using afterburners.
The trapezoidal flight booms around the engines were further enlarged, possibly to accommodate rearwards-facing radars, electronic countermeasures, and jamming equipment. The fuselage was extended to the engine's exhaust nozzles.
Compared to its "2014" and "2015" predecessors, the engine's surface area is further embedded inside the stealthy coating, providing greater rear-facing stealth against enemy detection.
On Thanksgiving of 2015, a new J-20 prototype, numbered "2017", took to the sky. The most significant change in the new prototype was the reshaped cockpit canopy, which provides the pilot with greater visibility.
The lack of other design changes suggested that "2017" is very close to the final J-20 production configuration.
Since '2017' was likely the last J-20 prototype, the low rate initial production (LRIP) of the J-20 is likely to begin as of 2016.
Chinese media reported that the design of the J-20 was frozen and finalized, as formal ceremonies were held for the prototype "2017" after completing the flight testing. The LRIP version later appeared in December of 2015.
In September 2018, it was reported that issues with the development of the WS-15 engine, particularly the reliability of the turbine blades overheating at top speeds were fixed.
The WS-15 reportedly required further development after failing final verification testing at the end of 2019. The COVID-19 pandemic imposed further delays. In March 2022, Chinese state media reported that the WS-15 engine completed final testing.
In November of 2021, the US military reported that the J-20 was gradually receiving upgrades. In the same month, new J-20 two-seater variant began flight testing.
In December of 2022, the prototype "2051" in yellow premier coat took flight. The new prototype had a redesigned canopy section and was speculated for engine and thrust-vectoring testing In March 2023, J-20 fitted with one Shenyang WS-15 engine reportedly performed experimental flights.
In June in 2023, the J-20 prototype "2052" equipped with two distinguishable WS-15 engines took flight in Chengdu, captured by Chinese military enthusiasts and spread throughout social media. Another prototype with serial number "2053" also reportedly conducted a test flight in the same period with WS-15 engines.
Despite the lack of clear pictures, circumstantial evidence such as a photo of the engine installation ceremony, lack of censorship by the authorities, and modified airframe suggested the WS-15 was evidently mounted, though Janes Information Services noted the engines on trial apparently lacks the thrust vectoring control (TVC) paddles, which could be added later.
According to the editor of Beijing-based Aerospace Knowledge magazine, vector thrust control and variable cycle engines were "likely under development". In 2024, clear photo evidence confirmed that J-20 prototypes took flight with the WS-15, and the engine approached the final stage of testing before serial production.
PRODUCTION
Aviation Analyst Rick Joe speculated the initial production batch of the revised J-20 model might enter service with WS-10 or WS-15 engine, depending on the circumstances surrounding the development.
In late December of 2015, a new J-20 numbered 2101 was spotted; it is believed to be the LRIP version of the aircraft. Chinese media suggested the stealth aircraft will enter production ahead of schedule.
In July in 2016, pre-production models with dark-grey paint and low visibility insignias were spotted inside a Chengdu Aerospace Corporation (CAC) facility. The production rate indicated an intended initial operational capability (IOC) date of around 2017–2018.
In October in 2017, Chinese media reported that CAC initiated the serial production for the J-20 and is on a path towards achieving full operational capability with the People's Liberation Army Air Force (PLAAF).
State media described the CAC's production rate as "stable", meaning achieving a regular production rate for minimal economies of scale. The production rate was expected to be three aircraft per month.
In 2019, CAC began manufacturing J-20 fitted with Chinese-made WS-10 Taihang engines. J-20s manufactured after mid-2019 were no longer fitted with Russian AL-31F turbofan engines.
The PLAAF began receiving WS-10C powered aircraft by 2021. The production rate of J-20 was expected to be further increased.
In January of 2022, United States Air Force (USAF) analyst Derek Solen estimated 50 to 74 fighters were in service based on open-source intelligence.
In August 2022, USAF analyst Li Xiaobing reported that over 150 had been delivered; claims of 150 being in service had been made in 2021.
Then in late-2022, Analyst Andreas Rupprecht estimated total production at 208 aircraft - including pre-production aircraft - based on interpreting serial numbers; an alternate interpretation with satellite images estimated 170-180. The International Institute for Strategic Studies (IISS) reported more than 140 aircraft in service in 2022.
According to Bronk, the aircraft at the 2022 China International Aviation & Aerospace Exhibition had visible improvements to manufacturing tolerance and quality control.
According to the Chinese military, CAC accelerated production and delivery by implementing a pulse assembly line.
J-20s on first deployment
According to Chinese military analysts, this was a response to increasing numbers of F-35 fighters deployed by the United States in the Asia-Pacific.
In mid-2024, Janes Information Services (JIS) estimated that approximately 195 aircraft were in PLAAF service, with more than 70 aircraft inducted between July 2023 and June 2024 in Xinping's government.
Deployment
According to the China Aerospace Studies Institute (CASI), three combat brigades received the J-20 by 2021, another three by 2022, and another two by 2024.
In March of 2022, USAF general Kenneth Wilsbach confirmed that USAF F-35s have encountered J-20s deployed over the East China Sea. In April 2022, Chinese state media reported J-20 started regular patrol in the South China Sea.
In June 2024, Janes reported 12 brigades with J-20s, of which three (1st, 9th, and an unidentified unit at Changsha-Ningxiang) were equipped only with J-20s.
Asia Times reported that PLAAF had prioritized deploying J-20s for airbases close to China's maritime border, and believed J-20's long combat range is well-suited for high-speed interceptions, strategic area defense, and long-range strike missions over the First- and Second-island chain.
All in all this is definitely a fighter to watch.
