Rong City, 611 Institute.
On the test runway, the yellow-skinned J-20 experimental aircraft with the number 2101 began taxiing, smoothly taking off propelled by its two Russian-made AL31F engines.
As Chief Designer Yang Wei watched Experimental Aircraft 2101 flying mid-circles, he contemplated the future of the J-20.
Four years ago, the first prototype Aircraft 2001 had its maiden flight.
According to estimates, around next year, the J-20 would enter its initial batch of finalized production and enter service.
But there was another problem with entering service: the engine.
The WS-15 "Emei" engine, designed for the J-20, seemed to be enduringly difficult to produce, not so much because of the technical difficulty but because the specifications were improving.
The current J-20 prototype still used the AL31F, and although the WS-10 was available, it was not yet mature enough.
