Shenyang WS-15

The Shenyang WS-15, codename Emei, is a Chinese afterburning turbofan engine designed by the Shenyang Aeroengine Research Institute and manufactured by the Shenyang Liming Aircraft Engine Company.

The WS-15 is intended to power and enable supercruising on the J-20, improve its maneuverability and range, and offers upgrade potentials for future weapon systems.

Design and development
Development of the WS-15 afterburning turbofan engine began in the early 1990s. In 2005, the engine performed successfully on the testbed. An image of the core appeared at 2006 China International Aviation & Aerospace Exhibition. In 2009, a prototype achieved 160 kN and a thrust-to-weight ratio of 9. The thrust target was reported as 180 kN in 2012.

In March 2022, Chinese state media reported that the J-20 had performed trials with the engine and experienced significantly improved performance.

In December 2022, Chinese military analysts indicated the WS-15 was undertaking the last stage of testing and development. Chinese sources suggested the engine completed its maiden flight earlier that year on an unknown airframe. In late December 2022, a prototype of the new J-20 variant was observed at Chengdu Aerospace Corporation facilities. The new variant was painted in yellow premier and different from previous J-20 aircraft in airframe and was speculated to be used to test the WS-15 engine and thrust-vectoring.

In March 2023, the executive of Aero Engine Corporation of China (AECC) announced the serial production of the WS-15 had started and China "[tackled] all technical bottlenecks" with the WS-15. FlightGlobal speculated that small-scale production run and in-flight testing with the J-20 fighter was underway. On 29 June 2023, a J-20B equipped with dual WS-15 engines was speculated to have made its maiden flight in Chengdu. Despite the lack of clear pictures, circumstantial evidence such as a photo of the engine installation ceremony, lack of censorship by the authorities, and modified airframe suggested the WS-15 was evidently mounted, though Janes noted the engines on trial apparently lacks the thrust vectoring control (TVC) paddles, which could be added later.

Defense analysts and commentators noted WS-15 was intended to be the ultimate engine for the J-20, providing supercruise capability, enhanced reliability, improved maneuverability, better fuel efficiency and longer ranges, extra electricity production, and upgrade potential for the fighter. Spending several decades of development, the induction of the WS-15 into the Chinese military was seen as a technological leap in China's domestic aviation industry.

Guizhou incorporated many of the same technology as on the WS-15 to develop the WS-19, a 10-ton thrust engine with the same footprint as the earlier Guizhou WS-13.