Actually when flying prototypes it is usually just the design concept of the bare airframe, then if there are changes dictated by aerodynamics, its no sweat to change the minimalist structure, so while all the features are in the design drawings and proposals, the hardware for weapons, doors, electronics are added after the flight test has proven the design sound. Now since this aircraft is not state sponsored-(according to some here on Sino D)- Shenyang may have gone with a more advanced technology demonstrator in order to show maturity and generate sales??? China is just now solidifying this process, and so it is difficult to "CALL". AFB
luhai-you are quite right about the J-20, and also the Liaoning, both projects have been "out there" in the public and have public support, and have been the source of great National Pride, as well they should be.....Makes it all the more odd to those of us here in the West, that the Liaoning is tied up pierside, the J-20 hasn't really advanced, and after the first flight the J-31 has become camera shy???? Brat