True... only US, U.K., France and Germany comes close. China still lags behind in metallurgy has problems with alloy components used in their engine which needs some maturing to do if my knowledge is up to date.... (2 years .....)
The tech of turbojet , related to nearly full-spectrum of basic industries, is the pearl of the mordern industry , which's even more sophisicated and harder than the tech of building a carrier.
Across the world, there're only three corporations with the capability of designing and building a cutting-edge turbojet that are GM , P&W and R&R, then following by the companies from Russia and France.
The theory of designing and building an turbojet could be absorbed by everyone, which's not a big deal.
The point is how to jump the hurdles of the puzzles of producing special alloy materials and kind of processing of one-time cast for sophisicated conponents with complicated structure ..
etc, all of which need out of number of tests in labs and plants , that means dozens of years of time and tons of money.
China has tried his best to catch up as soon as possible by reverse-engineering which could save us lots of time and money, but there are still too many efforts for Chinese to make in order to obtain this bright pearl.
The WS-10A has been used on J-10 series and J-11 series , and China would improve consistently its stablility and reliability , while the experience fixing varies of problems could benefit the development of WS-15 designed for J-20 and WS-13 with medium thrust for JF-17 and other turbojets for cargo plane and bomber .
China would catch up with US in the sphere in 10 years, cause we have decided to burn huge amount of money to shorten the process of the development.
