China Expanding Serial Production of J-20A Long Range Stealth Fighters with Enhanced WS-15 Engines

New footage released on Chinese social media has shown a J-20A fifth generation long range air superiority fighter still in yellow factory primary, indicating it has been produced recently, integrating twin WS-15 next generation turbofan engines. Video footage in December 2025 for the first time confirmed that the first batch of J-20s integrating twin WS-15 turbofan engines had completed serial production, with the first flight of a serial production aircraft with the engines reportedly having taken place on December 27. The WS-15 is a fully clean sheet new engine design, rather than an enhanced derivative of a pre-existing design, which makes its service entry a major landmark for the Chinese combat aviation industry. To place this in perspective, the last U.S. clean sheet fighter engine to enter service, the F119, was first flight tested in 1990 and began integration onto serial production fighters almost 30 years ago in 1997, with subsequent engines being derivatives of this or of older designs. 

Footage released by the J-20’s primary developer, the Chengdu Aircraft Industry Group, in January for the first time showed several of the new aircraft undergoing test flights with the WS-15. The integration of the WS-15 has long been anticipated, with the engine first seen integrated onto the J-20 in single configuration for a test flight in January 2022, before it was subsequently first flown in twin configuration in June 2023. It significantly improves all aspects of the J-20’s flight performance, as well as its range, while providing greater power to onboard subsystems and reducing maintenance requirements. As one of the most sophisticated fighter engines in production anywhere in the world, the WS-15 has a reported weight to thrust to weight ratio rivalled only by the F135 powering the F-35 fifth generation fighter among known engine types. Its efficiency expands the J-20’s already very long range, making it one of the world’s two longest ranged fighter types alongside the much larger Russian Su-34.

The entry of the enhanced J-20A and its new engine into serial production closely coincides with a significant expansion in the J-20’s production scale, indicating that the Defence Ministry may have been waiting until the fighter type could be brought up to a higher capability standard before investing more in procurements. This would be far from unprecedented, with production having expanded significantly from 2021 when the J-20’s design was previously enhanced and the aircraft began to integrate the WS-10C engines. A recent report published by the British Royal United Services Institute (RUSI) estimated that due to the significant expansion of production, the Chinese People’s Liberation Army Air Force will field approximately 1,000 J-20s by 2030. Production is expected to be sustained at approximately 120 fighters per year. No other fighter type is being procured on even half this scale by any other service in the world, with these investments combined with the J-20’s world leading capabilities expected to expand the PLA Air Force’s already extreme advantages in its air-to-air combat capabilities. WS-15 engines are expected to fully replace WS-10C engines in production in 2026, and may have already done so.