
America’s F-35 vs. China’s J-20s: Which Fighter Jet Reigns Supreme?
China’s rapid military modernization campaign includes the rapid addition of larger numbers of its J-20 5th-Generation aircraft, something which undoubtedly raises the question as to whether the Chinese jet is comparable to the U.S. F-35.
There has certainly been much discussion about how elements of the external configuration appear to mirror, mimic or potentially even “copy” design attributes of the F-22 and F-35.
In recent years, several Pentagon reports have pointed this out as well, as it is something which raises key questions about the actual extent to which it may compete with or rival the F-35.
One initial thing of consequence is simply that, at least thus far, the People’s Liberation Army – Air Force only operates a number of J-20s and operates a fleet size well below the capacity of the Pentagon’s F-35 program which calls for 1,763 of the jets for the Air Force.
Given that “mass matters” should there be an actual great power conflict, China would at this point appear to be operating at a deficit, regardless of the extent to which it might match the F-35.
However, there is certainly much to observe when it comes to China’s production rates and capacities, especially in the areas of shipbuilding. This could certainly extend to aircraft construction as well.
China’s J-20
As for the external configuration of the J-20, it certainly appears stealthy as it incorporates a horizontal, blended wing-body exterior with a rounded, gradually sloped structure.
Naturally such a design is intended to general a much lower and less detectable radar cross-section. Vertical structures or protruding formations can of course generate a stronger “return” signal in response to electromagnetic “pings” intended to bounce off and send back a return signal or rendering. Interestingly, the back portion of the plane appears to mirror an F-22 to a greater extent than the F-35, as the plane has dual exhaust suggesting the presence of a dual engine design.

While there are likely internally buried internal engines and measures of thermal management technologies, may elements related to coating materials, heat signature management or engines are likely difficult to come by. The Chinese newspapers did write about the J-20 now being built with a domestically-produced WS-15 engine.
More recently, the Chinese papers and the Pentagon’s China report cited PLA efforts to upgrade the J-20 to rival the F-22 with “supercruise” ability. The Defense Department’s report to Congress on Military and Security Developments Involving the People’s Republic of China, discusses Chinese efforts to install thrust-vectoring nozzles to add “supercruise ability.”
However F-22 “supercruise,” which enables the jet to sustain Mach speeds without needing afterburners, may be difficult to replicate. It is not clear or apparent that Chinese engineering can actually match F-22-like speed and aerial maneuverability. In similar fashion, it may not rival the F-35 in these respects either, as there are certainly so many unknowns.
F-35 and J-20 Comparison
This pertains to other elements of F-35-J-20 comparison.
The true margin of difference may reside in a series of unknowns, meaning superiority would likely be determined by mission systems, weapons and targeting, computing and sensing.
Therefore, regardless of the extent to which the external configuration of the J-20 might parallel the F-35, there may be little or no indication that the J-20 would be able to rival the F-35 in terms of sensor range and fidelity, “sensor fusion” kinds of computing and weapons guidance technology.
Could a J-20 even see an F-35 before it were found and targeted by an F-35?
Does it operate with any kind of comparable high-speed computing able to organize incoming sensor data with AI-like data analysis to present an integrated view to pilots?
Does it have AIM-9X-like off-boresight targeting technology or other weapons with advanced guidance systems, hardening against countermeasures and precision attack.
Does the J-20 have anything comparable to the F-35s Missile Data Files threat library able to instantly bounce new incoming information off of a threat library to make rapid identifications? Finally, are there built-in technical standards such that the J-20 can continuously be upgraded with software enhancements to match or rival the F-35 in coming years?
The F-35, which will soon drop unparalleled weapons such as the Stormbreaker, is engineered with an ability to accommodate new weapons, fire control technologies and guidance systems as they become available in coming years? The Pentagon plans to fly the F-35 until 2070 and beyond.
The answers to many of these questions pertaining to the J-20 may be unknown, however it does not seem likely that a J-20 could match all of these attributes. If not, it cannot match the F-35. If so, that may be a different question.