The J-20 vs. F-22 debate has been ongoing for more than twenty years. Both fighters are capable of performing combat missions, and both offer benefits to the fleet. The combat experience could be transformed by a new technology. Airborne Tactical Augmented Reality System (ATESA) would allow a pilot to interact with a simulated J-20 enemy. This technology could reduce air combat training costs, and solve tactical problems that fleet aviators face.
WS-10C Engine
There are rumors that China will replace the Russian engine in the J-20 with a homegrown WS-10C engine. China's military wants to reduce dependence on foreign engines and the new engine is expected be more reliable. But, when comparing the engines, one must be aware of the differences.
In January 2021, the PLA Air Force confirmed that the J-20 will be equipped with a domestically developed WS-10C engine. This information was made public by the PLA Air Force in a video that promoted a pilot recruitment program. The domestically developed WS-10C engine is expected to help the J-20 gain maneuverability. A number of J-20s entering service will also indicate that the aircraft's technical capabilities are improving and is nearing mass production.
WS-15 nozzle
The WS-15 nozzle was designed to provide excellent maneuverability and high thrust for the J-20. It is a considerably more powerful jet motor than the F119 and will provide unmatched performance for the J-20. The WS-15 can also be used with thrust vector control.
PLAAF has spent more than $4.4 Billion on the J-20 program, each J-20 costing around $120 M. China currently tries to replace the Russian AL-31 engines with its own WS-15 nozzles. However, China has not been able to replace as many of the Russian engines as originally anticipated.
AESA
The two aircraft are similar in their capabilities, with the main differences being the engine and range. The Russian AL-31FM2 Russian engine is used to power the J-20. It produces 145kNs of thrust. While the F-22 uses a 180kN engine, it produces 145kN. The stealth designs of both aircraft appear similar, although the F-22's axisymmetric nozzles are visible to radar and would compromise stealth.
Both the F-22 as well as the J-20 are AESA equipped and can store their weapons inside of internal bays. However, the J-20 possesses a number of unique features that set it apart from its American counterpart. It is a twin engine configuration that canard-delta has with supersonic intakes deviated-less and a shaped nasal. The F-22's gun system is only available for the J-20, which has an active electronically scanned area (AESA), radar.
Infrared tracking and search
The IRST sensor is normally installed in a spherical, glass enclosure at the front of fighter aircrafts. It can scan an instantaneous target's field of vision using either a Staring array or a single component. While this sensor does not detect distances as well as radar, it can provide accurate information about the locations of targets.
The IRST sensor, however, is older-style and less powerful than civilian surveillance cameras. It will not be as effective at detecting targets at 80km, and it won't be as fast at 20-30 km. The F-22 is more stealthy than the J-20 and will be quicker and more stealthy.