|J-20 proves that it uses WS-15 engines as there are no grooves on the nozzles of its engines.|
|The nozzle of Russian AL-31F engine used on J-20 prototypes. There are two groves on the nozzle|
|Engine with no grooves on it|
Its reliability lies between Western and Russian ones with a life of 900 hours longer than AL-31F.
Since the engine problem has been solved, J-20 can be regarded as a capable modern stealth fighter as it has satisfactory electronics and stealth shape.