There have been little to no actual "sightings" of the J-20, and some wonder if the aircraft could be a stealthy bomb-truck and ground and surface attack aircraft without a clear or defined mission

By Kris Osborn, President, Center for Military Modernization

China’s J-20

Maneuverable, high-speed, air-dominant F-22 competitor, advanced, AI-enabled forward sensor node, bomb truck supporting land and amphibious assaults, stealthy air supremacy platform able to destroy enemy air defenses and advanced air-to-air attack platform .... are all possible missions for China's fast-growing fleet of J-20s.

Despite the fact that open sources say there are now more than 208 operational J-20 5th-generation stealth jets, the fighter has been conspicuously and curiously absent from view.

There have been little actual "sightings" of the J-20, and some wonder if the aircraft could be a stealthy bomb-truck and ground and surface attack aircraft without a clear or defined mission.

Former officials suggest that the lack of flight hours also means there is much less pilot training and pilot experiences with the J-20, yet another reason why questions about the J-20s mission, intent and actual capability persist.

Specifically, an interesting and as-of-yet-to-be published research essay called "PLA Flight Activity in Taiwan's Air Defense Identification Zone,” from a group of expert researchers uses precise data to document the number of Chinese aircraft violations of Taiwan's ADIZ. The researchers based their findings related to PLA Aircraft violations on data compiled by Taiwan’s Ministry of Defense.

The figures paint a picture of growing Chinese aggression, as their research reveals that Chinese aircraft violations of Taiwan's ADIZ airspace tripled between 2020 and 2023, showing a massive uptick in provocative aircraft behavior and intimidation tactics.

No J-20 in Taiwan ADIZ

Each ADIZ violation with specific identification of aircraft type is precisely documented by the researchers spanning back several years, and yet there has in recent years been "not one" J-20 sighting in Taiwan's ADIZ, according to the researchers. Considering the importance of preparing and training pilots on a 5th-Gen stealth fighter and ensuring the jet is mission ready, some consider the absence of the J-20 in Taiwan's ADIZ as a particularly mysterious and possibly even revealing development.

Certainly the large-scale uptick in violation flights, which jumped from 972 in 2021 to 3,119 in 2022, can be interpreted along the lines of several axes of thought, including war drills and invasion preparation, potential testing of newer technologies and related Concepts of Operation and of course conducting extensive surveillance of Taiwan and US surface and undersea assets.

China Has 208 or More J-20s

In November 2022, high-resolution photos published in several news publications and public sources revealed over 208 J-20 fighters have been built, and experts publishing open source material on the Chinese Air Force say a total of four batches of J-20 have been delivered by 2022 with 18, 46, 56, and 70 airframes for each shipment.

Certainly Chinese papers write about the J-20s maturation, demonstrations and technologies such as its WS-15 domestically-built engine, yet apart from a few training missions, the J-20 has not been airborne much near areas where it might be seen up close. This was the thinking of one prominent Chinese expert researcher and former high-level US military official who suggested that perhaps the J-20 was kept from flying within Taiwan’s ADIZ to prevent it from being seen by Taiwan’s air defenses, surveillance planes or fighter jets at close range.

Does the J-20 truly have a clear mission? Are pilots actually training on J-20s to test its performance parameters and technological prowess? Does the PLA Air Force actually have a very different mission intention with its J-20 than may be largely recognized? These seem to be valid questions. Despite being touted as an F-22-like air-supremacy stealth fighter, perhaps the J-20 is far less threatening and intended to operate more fully as a "bomb-truck" type of aircraft in support of surface and ground attack.

An experienced China Military analysts pointed out that here appears to be somewhat of an impasse or disconnect between China's known "Train As You Fight" mandate and actual J-20 training practices. If few to no J-20s are ever sighted over water or seen training in any capacity, then one must wonder if China's J-20 force is ill-equipped for combat. How can J-20 pilots prepare for maritime combat missions and all the variables it encompasses without actually flying the aircraft in different conditions.  Certainly pilots would need to assess and practice the aircraft's ability to see through clouds, maneuver in obscured weather circumstances and perform accurate air-to-surface or air-to-air targeting. 

In terms of pure speed and thrust-to-weight ratio, there are some interesting observations to be made, as the J-20 is reported to be faster than the F-35, yet not as fast as the F-22 Raptor. The J-20 is listed as being able to operate at a max speed of Mach 2.0 and the J-31 is slated with speeds up to Mach 1.8. Speed for both the J-20 and J-31 are less than the F-22s Mach 2.25 speed, yet faster than the F-35s speed at Mach 1.6. The F-22 also has the most advanced thrust to weight ratio in the world, and is therefore able to maneuver, vector and out-run enemy air-to-air and air-to-ground missiles in ways that are likely to be unrivaled.

J-20 Bomb Truck

The J-20 does operate with a “bomb-truck” like capacity to deliver more ordnance than an F-35 on a single mission, as it can take off with 27,998 pounds of internal and external ordnance, compared with an F-35 in beast mode which can travel with 18,000 pounds of weapons. The J-31 can also travel with a heavy load of weapons, as its maximum take-off capacity is listed as being at 28,000 kg.A full internal and external weapons complement, however, would certainly compromise stealth by generating a larger and more precise radar return signal to adversary air defenses.

Stealth properties can be optimized if temperatures emitting from or surrounding the aircraft align with or somewhat match the surrounding temperature, thereby concealing or removing thermal signature.

The structure also includes the kind of conformal, blended wing-body shape of many fifth-generation fighters, complete with rounded back end exhaust emissions.The F-35 and F-22, by contrast, have singular gradually sloped-horizontal wings. A shorter protruding, yet aligned or sloped wing, followed by longer wings, might represent an attempt to improve stealth performance. A dual-wing formation could, it seems, interrupt the speed of the aerodynamic airflow on each side, potentially better managing temperature.

Top former experts and US officials, who conducted and published public, unclassified open-source material for US Military public publications, suggested that the absence of the J-20 from the Taiwan ADIZ may also pertain to its mission scope, as it is not necessarily built for an F-22-like air supremacy mission and is instead larger with “dual-wings” and an elongated fuselage. This raises questions about the extent to which it could maneuver and prevail in air-to-air combat engagements, suggesting that perhaps the Chinese might intend a more limited role for the aircraft. This may be largely unknown to a degree and it would likely depend upon the range, fidelity of its sensors, processing speed of its on-board computers and other tough to determine factors. The extent of the J-20s sensing, targeting and computing may be quite difficult to discern, yet report from the Chinese-government backed Global Times several years ago says the J-20 was “spotted” flying without a Luneburg lens, a small device used to intentionally expose a stealth aircraft to others in situations like training or non-combat flights.

J-20 Dual Engine & Stealth

Interestingly, the J-20 reveals a dual-engine configuration, something which mirrors an F-22 as opposed to an F-35. This may indicate an attempt to achieve an F-22-like supercruise technology that enables sustained speeds without needing an afterburner, something that helps expand mission time and improve aerial performance.

Also, the top of the J-20 has dual rounded “humps” that look nearly identical to the top of an F-22. In contrast, the F-35 has a single rounded parabola like fuselage on top, whereas the J-20 and F-22 reveal a flat upper fuselage blended into two separate rounded engine pathways. This kind of engineering might also be an effort to maximize maneuvering, vectoring and aerial dogfighting capabilities similar to those known to be possible with an F-22.

All of this raises significant questions about various characteristics of the J-20, such as its speed, stealth performance and maneuverability. While much of the specifics of the J-20 could simply remain a mystery, the aircraft may not truly rival the F-22 or F-35, despite the apparent external similarities. Much of this also relates to unknowns, while a stealth fighter’s ultimate success is related to stealth configuration, its true margin of superiority may lie in its sensors, weapons, avionics, temperature management and internal construction.

Also, if a Chinese J-20 does not have targeting sensors or computing that was in any way comparable to the F-35, other attributes would not even matter much. In short, whichever aircraft is best able to complete the OODA Loop (Observation, Orientation, Decision, Action) and operate within or ahead of an enemy’s decision cycle is likely to prevail by destroying the enemy faster than it can itself be hit. Completing this process requires expedited sensing, computer processing, data analysis and integration, all F-35 attributes which may or may not be matched by adversary 5th-gen aircraft.

J-20 vs F-22

With less speed than an air-dominance F-22 and a weaker thrust-to-weight ratio, the larger and arguably less stealthy J-20 is not likely to truly rival an F-22, according to many top observers. In an essay several years ago, Justin Bronk with the London-based Royal United Service Institute, makes the point that J-20s would be outmatched in the air by U.S. F-22s deployed to challenge them.

Bronk writes that the J-20 “is a heavier, less agile aircraft that will be more expensive to build and operate. It also cannot compete with the extreme performance or agility of the F-22.”

The J-20 aircraft has a short set of sloped, horizontal wings followed by larger structures aligning across the back end of the body. Perhaps this represents an effort to break up or smooth out the airflow passing on either side of the fuselage; airflow at high speeds can generate heat signatures potentially vulnerable to detection from enemy air defenses.

The J-20 has also rarely flown any sorties into the East China Sea or South China Sea. As a land-launched stealth platform, the J-20 may have limited reach without operating with not-so-stealthy large tankers, although the jet can clearly go the 100 miles from mainland China to Taiwan.

There is one previous instance cited and hyped up in the Chinese government-backed Global Times newspaper which quotes a US Air Force general (Wilsbach) praising the J-20s flight abilities and command and control following a reported "sighting" or encounter. However, the full extent of what was observed may be difficult to discern and US Air Force generals often express concern regarding the potential threat posed by the J-20. The incident is quite significant, however, as a 2022 CNN report cites US Air Force Gen. Kenneth Wilsbach, Commander of US Pacific Air Forces, saying that "F-35s" intercepted the Chinese J-20s.  The CNN essays cites the general explaining the aircraft "came into close proximity with each other over the East China Sea." 

The capabilities and mission plans for the J-20 are likely to remain elusive for quite some time, given its conspicuous absence from training missions or visible flights, yet China is amassing a sizeable fleet of the aircraft and does often report on the J-20’s attributes. The J-20 is particularly critical for PLA Air Force in terms of projecting 5th-generation air power beyond its borders. The J-20 is a land launched aircraft, and the PLA’s carrier-launched 5th-Gen J-31 is not here yet, placing China at a massive 5th-gen deficit over the ocean. However, should operations take place within several hundred miles of the Chinese coastline, then yes J-20s could figure prominently, yet being restricted to land launch and take-off massive limits the aircraft’s reach.

Perhaps China sees the J-20 as an aircraft which could provide a decisive advantage along the Indian border given India’s lack of F-35s? Or perhaps the PRC envisions a “bomb-truck” like J-20 as a platform to target and attack Taiwan’s air defenses? Or both? Neither of these scenarios amount to the J-20 as any kind of air-to-air air dominance fighter or highly maneuverable stealth jet capable of destroying next-generation air defenses. Therefore, despite being compared to the F-22 and F-35 quite often, and revealing configuration similarities to an extent with US 5th-gen aircraft, China’s J-20 may have a much different concept of operation and mission scope than may be broadly realized. 

Kris Osborn is the President of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a Highly Qualified Expert with the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University