Beyond China’s J-20 Stealth Fighter

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Beyond China’s J-20 Stealth Fighter

Is a carrierborne FC-31 in the works? And what about Chinese 6th generation prospects?

Beyond China’s J-20 Stealth Fighter
Credit: Chinese Internet

With the J-20 stealth fifth-generation aircraft entering service with front line combat units in the PLA Air Force (PLAAF), it is likely that the initial variant of the J-20 is approaching the completion of its development program. This marks a suitable time to start considering what is known, rumored, and not known in regard to Chinese stealth fighter initiatives beyond the J-20.

In particular, this piece will review the likely trajectory of the carrier based 5th generation fighter intended for the PLA Navy (PLAN), as well as early indicators for prospective Chinese 6th generation fighters. Given the secretive nature of the topic matter as well as the long timelines involved for Chinese 6th generation efforts, much of this piece is preliminary and likely subject to change as new information comes to light in coming years.

A Carrierborne FC-31?

Rumors of a carrierborne 5th generation fighter began to emerge not long after the first J-20 prototype made its first flight in early 2011. When the export oriented FC-31 airframe then emerged in October 2012, its smaller size and more conventional configuration and externally more sturdy appearing landing gear oriented speculation toward whether the FC-31 would be developed into a carrierborne fighter.

For a number of years, rumors suggested carrierborne variants of both the J-20 from Chengdu and the FC-31 from Shenyang were engaged in a contest to be the PLAN’s carrierborne 5th generation fighter. The two baseline aircraft occupied different weight categories, with the J-20 being the heavier and larger of the two, and debates on open forums often considered the benefits and costs of one design over the other. In December 2016, an improved second prototype of the FC-31 flew with some major structural modifications to its canopy, wings and tails, however this second airframe did not feature any modifications suggestive of intended carrier compatibility

In the last two years however, some rumors have suggested that the PLAN has finally settled on the FC-31 airframe as the basis for its 5th generation carrierborne fighter. The exact designation of this aircraft is not known, but it has sometimes been designated as “J-35” on Chinese language PLA boards, though the seriousness of the name is unknown. Some recent articles have suggested the PLA seeks a J-20 variant for a carrierborne fighter variant, but to the best of this author’s knowledge this is contrary to the consensus of Chinese language military watching boards.

The Role of a 5th Generation Carrier Fighter

The parameters of a carrierborne FC-31 variant/J-35 aren’t known, though some rumors have suggested the aircraft may have a maximum takeoff weight of about 30 tons (similar to the F-35). The aircraft would be initially powered by two nine ton thrust class WS-13E engines (improved Chinese copies of RD-93), and to be later powered by 10-11 ton thrust WS-19 engines in the late 2020s (in a thrust class of F414 or EJ200). The use of interim engines for the carrierborne FC-31 variant will not be dissimilar from the J-20’s use of interim engines prior to receiving intended its WS-15s. However, there have been some indications that the WS-19’s development cycle may be slightly shorter than the WS-15, as it may have benefited from cross applicable research and development originally conducted for the WS-15.

The aircraft will almost certainly have reinforced landing gear, folding wings and a tailhook for carrier operations, as well as a catapult compatible nose gear for operations aboard the PLAN’s future catapult carriers such as 003 and beyond. The carrierborne 5th generation fighter is currently projected to make its appearance in late 2019 or early 2020 at the earliest, however it’s not known how long the aircraft may take to develop before entry into service. Certain factors may favor a longer development period (such as it being a 5th generation carrierborne fighter), but other factors might compress it somewhat as well (such as Shenyang having flown two preceding demonstrators for many years, and possible adaptation of J-20 subsystems and avionics in it).

Another major unknown factor is whether additional J-15 aircraft will be produced for Chinese aircraft carriers before the 5th generation carrier fighter enters service (which would not be before than the mid 2020s at the earliest). A catapult compatible J-15 testbed has been developed and trialed, and an electronic warfare ski jump compatible J-15 prototype is also in testing, however at present there are no indications that additional J-15s have been constructed beyond the initial 24 airframes. It goes without saying that a modernized, catapult compatible J-15 could act as a stopgap for a 5th generation carrier fighter as well as to complement it in a similar way to how U.S. Navy Super Hornets will complement F-35Cs. But at present there are no indications of continued J-15 production despite testing of at least one new advanced variant.

The World Beyond the 5th Generation

A number of nations around the world have started programs to develop fighter aircraft beyond what is currently known as 5th generation fighters. These tentative 6th generation programs are currently in their infancy and remain appropriately secretive.

The United States is currently developing the closely guarded Penetrating Counter Air (PCA) as part of its “Next Generation Air Dominance” concept, with a goal of entering service as early as 2030 for the U.S. Air Force, as well as a U.S. Navy project called F/A-XX intended for a similar date into service. The Franco-German Future Combat Air System (FCAS) is a similar next generation fighter project intended for entry into service by 2040. The UK’s Project Tempest has been stated to enter service by 2035. All of these publicly announced projects remain relatively early in development and have been variously described as “next generation” or “sixth generation” by commentators and defense media over time.

However, the exact subsystems and technological advances that may prove to be decisive in “6th generation” fighters are unclear. Various systems have been posited as potential advancements to expect from next generation air combat systems, including integration of unmanned aircraft into manned-unmanned teaming (MUMT), artificial intelligence, system of systems warfighting concepts, long range and endurance, broadband stealth, future propulsion systems such as variable cycle engines (VCEs), and directed energy weapons (DEWs).

The exact configuration of these future air combat systems may not be known, but at present it appears that a manned fighter aircraft will still play a central role despite heavy hints of MUMT and system of systems approaches. If the relationship between 5th generation and 4.5th  generation aircraft are any guide, it is very possible that certain future technologies for “6th generation” aircraft may be applied on current 5th generation aircraft to become “5.5th generation” in turn.

Hints of a next generation fighter

The PLA and Chinese aerospace industry has made impressive advances in recent years and decades to close technological gaps with other leading world military powers. As nations around the world begin to develop 6th generation fighter aircraft and next generation air combat systems, it is likely that China has begun to conduct research and development along similar lines. Assuming that China is aiming to field their equivalent of a 6th generation fighter along a similar time period to U.S., UK and European concepts, pre-research would have likely begun quite a few years ago.

Given traditional Chinese opacity towards leading edge military advances, it was expected that many years might pass until official acknowledgement of a next generation fighter project.

However in early January 2019, the WeChat account of AVIC Times published an interview with Dr. Wang Haifeng, the current chief designer of Chengdu Aerospace Corporation (CAC). One section in the interview provided some surprisingly candid statements regarding a next generation fighter concept.

In this section, Wang first comments on the next generation fighter concepts that have emerged from the U.S. and from Europe. He then lists various technologies that he believes will likely become important in that generation of aircraft such as MUMT, artificial intelligence, very high stealth, omnidirectional sensors and weapons, as well as other less certain technologies such as VCEs, DEWs, hypersonic weapons, and swarming technology.

Astonishingly, he then states that not only has China already been conducting pre-research for a next generation fighter, but also that he predicts current efforts will progress to become weapons to “defend the seas and skies” by 2035 or earlier. Considering the context of the sentence and the choice of words used – specifically “defend the seas and skies,” as opposed to “first appearance” or “emergence” – the interpretation from Wang’s statement is that he expects a next generation Chinese fighter to be in service by 2035 or earlier. Much uncertainty remains currently as to what exactly a 6th generation air combat concept may look like, however it appears a future manned fighter may be part of it for China.

Beyond this statement, there have been other hints that research and development into relevant subsystems has been ongoing. In an article from China’s Science and Technology Awards in June 2018, Liu Youngquan of Aero Engine Corporation of China (AECC) stated that advancements in developing variable cycle engines have been made, including developing key verification technologies and construction of a key technology system. In fact, as early as 2012, Zhang Jian of the preceding AVIC Engine Company confirmed that China was conducting research and development into variable cycle engines. Chinese interest in MUMT have also been strongly suggested, with multiple unmanned aerial vehicle (UAV) programs known to be ongoing, and a swarming UAV concept from Zhuhai Airshow 2018 depicted a generic tailless future fighter controlling swarms of drones.

Projecting Potential Milestone Dates

Overall, the balance of indicators strongly suggests research and development into 6th generation fighter and air combat concepts has been ongoing for a number of years now, and Wang’s statement of a next generation fighter entering service by 2035 or earlier creates a basis to estimate when prototypes or demonstrators for such an aircraft could be expected to emerge.

For the sake of brevity, this notional PLA 6th generation fighter will be dubbed as “J-X.” Note this is not an official designation or a name used in the community.

If J-X is intended to enter service in 2035, then going by past fighter programs it suggests a maiden flight should occur at least 5 years prior. Assuming an additional 2 years of development given potential delays, a service date of 2035 implies the prototype for this aircraft would have to emerge by 2028 at the latest. For J-X to enter service in 2035 would require it to likely begin low rate production a couple of years beforehand (again, when derived from practice of recent projects like the J-20). That would project initial production of J-X to begin around 2032-33 at the latest.

Using the above hypothetical dates, some simple arithmetic allows various milestones to be calculated between J-X and the previous generation J-20:

  • J-20 maiden flight in early 2011, 17 years before J-X’s projected maiden flight.
  • J-20 initial production began in 2016, 16-17 years before J-X’s projected initial production.
  • J-20 entered service in combat units in 2018, 17 years before J-X projected service date.

Those above numbers can in turn be compared to the time taken between J-20 to reach those milestones compared to its previous generation J-10:

  • J-10 maiden flight 1998, 13 years before J-20 maiden flight.
  • J-10 initial production began in 2003, 13 years before J-20 initial production.
  • J-10 entered service in combat units slightly after 2004, about 14 years before J-20 entered service.

Therefore surprisingly, in terms of the passage of time between generations, the projected time taken between J-X and J-20 for various important milestones would actually be longer than intervening period between J-20 and J-10. Additionally, even if J-X does enter service in 2035, it is likely that advanced J-20 and/or FC-31 variants will still remain in production. After all, even as J-20 has recently entered combat service, China today continues to produce 4+ generation J-10C and J-16 fighter aircraft in the interim.

Wang’s potential 2035 service date for the next generation fighter is only 16 years away when measured from the present day in 2019. 16 years may seem quite close and it may be difficult to envision such major advancements occurring in such a short space of time. However, in 2003 it likely would have also been as difficult to comprehend the idea of the Chinese aerospace industry producing an aircraft like J-20 and commissioning it in service merely 16 years into the future. As the years pass and enter the early 2020s, it is likely that additional rumors and indicators will emerge for the Chinese 6th generation fighter just like it did for J-20 (then known as “J-XX”) during the early and mid 2000s.