China puts advanced WS-15 engines through J-20 stealth fighter paces

Footage circulating online shows jet fitted with long-awaited domestic engines in test in Chengdu
Lack of censorship of posts amounts to quasi-official confirmation of maiden flight, analyst says

China’s military

Minnie Chan

Published: 9:00am, 5 Jul 2023

Why you can trust SCMP

After two decades of development, China’s most powerful engine has had its maiden flight in one of the country’s most advanced stealth fighters, an upgrade that defence analysts say narrows the technology gap with the United States.

According to a video circulating online since June 28, a J-20 prototype jet fighter fitted with two WS-15 engines took off from a test airfield in Chengdu, southwest Sichuan province.

The city is the base of the J-20’s developer, Chengdu Aerospace Corporation.

It is unclear when the flight took place and there was no official announcement from the People’s Liberation Army.

But photos and footage of the test have been circulating freely on social media platforms at home and overseas, a sign of official endorsement in China’s heavily censored information environment.

Footage of the J-20 with its tailor-made WS-15 engine has been circulating online. Photo: Weibo

Military enthusiasts also posted clips of the J-20’s maiden flight with Russian AL-31 engines in 2011 and Chinese WS-10Cs in 2021, comparing them with the most recent test.

“The lack of censorship of social media posts about the latest maiden flight represents quasi-official confirmation of the successful development of the WS-15 turbofan engine,” said Zhou Chenming, a researcher of the Beijing-based Yuan Wang military science and technology think tank.

“With the new WS-15, we can see the J-20 is much more manoeuvrable and faster in climbs, showing it is almost on a par with the American F119 engine designed for its F-22 and F-35 stealth fighters.”

Zhou said the WS-15 would be fitted to the J-20B variant of the fighter, overcoming a major “heart problem” with the aircraft.

“After 12 years since the J-20’s maiden flight in 2011, the Chinese air force finally got the engine it had long been waiting for,” he said.

“The accomplishment of the sophisticated WS-15 engine means the PLA Air Force will no longer [be at risk of a] ‘heart attack’.”

China’s air force has been waiting a long time for the domestically developed jet engine, an analyst says. Photo: Weibo

But former PLA instructor Song Zhongping said the WS-15 did not yet have the endurance of the American engines, which can exceed 500,000 flight hours.

“There is still a gap between WS-15 and the F119 engines,” Song said. “It’s an experimental success for the WS-15, but it’s too early for it to enter mass production. It still needs tests and improvements.”

China is keen to have a stealth aircraft capable of competing with the best in the world as tensions rise in the Asia-Pacific and the United States ramps up deployment of its fifth generation F-22 and F-35 fighters in the region.

The PLA introduced its most advanced J-20 in March 2017, an aircraft with Russian AL-31 engines.

China has produced at least 200 J-20 fighters, most of them powered with AL-31 engines, with the thrust-vectoring WS-10C engine as stopgaps.

Meanwhile, the US plans to deploy up to 300 of its stealth fighters to the region by 2025, according to earlier reports by the Post.