Mach What: How Fast Is China’s New J-36 Stealth Fighter?

Key Points and Summary – China’s rumored sixth-generation J-36 is being marketed as a “need for speed” stealth fighter, with reports pegging it at roughly Mach 2.5.

-That figure is unconfirmed, but it raises the real question: what design choices could make a large, low-observable aircraft that fast?

J-36 Fighter in the Sky. Image Credit: X Post.

China J-36 Fighter Takeoff. Image Credit: X Screenshot.

-The article explores likely propulsion options, from upgraded WS-10 variants to the long-anticipated WS-15, and what a possible tri-engine layout could mean for thrust, range, and thermal management.

-It also looks at the J-36’s tailless delta planform and unusually large wingspan—features that may balance speed, efficiency, and signature control in China’s next airpower play in the Pacific.

Mach 2.5 J-36: China’s Big Bet on “Speed Is Life” Airpower

As the fictitious, then-LT (USN) Pete “Maverick” Mitchell (now a Captain, Maverick, although he should be a Rear Admiral by now, as his commanding officer notes) said in the original Top Gun film back in 1986, “I feel the need for speed.”

Meanwhile, Maverick’s real-life fighter pilot counterparts have the motto “Speed is life.” Granted, the two fastest airplanes ever made, the rocket-powered North American X-15 (Mach 6.7) and the jet-powered, air-breathing Lockheed SR-71 Blackbird (Mach 3.56), weren’t actually fighter planes, but eh, why nitpick?

Now, mind you, the political and military leaders of the People’s Republic of China (PRC) are no fans of the Top Gun film series.

They were absolutely up in arms about the fact that the back of Maverick’s leather bomber jacket prominently sported a Taiwanese flag patch (to commemorate his dad’s battleship tour there in 1964). They also reportedly freaked out at the appearance of the SR-72 “Darkstar” in the sequel so much that they actually re-oriented spy satellites to get a glimpse of the full-size mock-up that the film’s crew built for that epic opening scene.

That said, the PRC’s People’s Liberation Army Air Force (PLAAF) still concurs with America’s cinematic and real-world fighter pilots alike about the need for speed, as is evidenced by the plethora of supersonic warbirds in the PLAAF fleet. And that same philosophy is being carried over to their up-and-coming Chengdu J-36 6th Generation fighter, which reportedly has already achieved a maximum speed of Mach 2.5 (1,918.17 mph, 3,087 km/h, 1,666.85 knots).

However, a word of caution: being a new fighter jet, it is not possible to confirm that number. But if true…

J-36 Fighter X Screenshot Image.

J-36 Fighter YouTube Screenshot/Artist Rendering.

J-36 Fighter Artist Rendition from X Screenshot

How Does the J-36 Achieve That Speed?

If that reported Mach 2.5 figure is correct, that would make the J-36 faster than either one of Maverick’s jet fighters, the Grumman F-14 Tomcat (Mach 2.34) and the Boeing F/A-18E/F Super Hornet (a comparatively plodding Mach 1.6), and puts it on a par with the McDonnell Douglas/Boeing F-15 Eagle.

That would also make it faster than both of America’s 5th Generation stealth fighters, the F-22 Raptor and the F-35 Lightning II (both of which are produced by Lockheed Martin’s legendary Skunk Works division).

The source of that Mach 2.5 figure is a December 30, 2024, article by Dan Arkin of IsraelDefense titled “The Maiden Flight of the J-36 Fighter Jet: A Breakthrough in China’s Aerospace Industry.” Therein, Mr. Arkin also mentions that the J-36 is “a powerful tri-engine aircraft” but doesn’t go into specifics.

That’s not surprising, as the J-36 program is understandably still shrouded in secrecy.

That said, we can reasonably speculate that the powerplant is either the WS-10 or the WS-15 (codename “Emei”) afterburning turbofan engine, both of which are produced by the Shenyang Aeroengine Research Institute, a subsidiary of the Aero Engine Corporation of China (AECC).

The WS-10 is what currently powers the PLAAF’s Chengdu J-20 Weilong (“Mighty Dragon;” NATO reporting name “Fagin”) 5th Generation stealth fighter, whilst the WS-15 is the intended replacement for the next batch of J-20 production.

As noted by the Editorial Staff of Military Watch Magazine in a March 27, 2023 piece, “The WS-15 is expected to not only have a much longer life and lower maintenance requirements than the WS-10, but also a massively greater power output which will give the J-20 more thrust than any other tactical combat aircraft in the world. The engine is also expected to introduce two or three-dimensional thrust vectoring capabilities for improved manoeuvrability.” As it is, the WS-10 engine is certainly no slouch, as it generates 135 kilonewtons (30,000 pounds-force) of thrust and enables the J-20 to attain a top speed of Mach 2.0.

Another possibility is the Guizhou WS-13 (codename “Taishan”), which powers the PRC’s other stealth fighter, the J-35. The WS-13 is a modified version of the Russian RD-33 engine, and generates 86.37 kN (19,420 lbf) with afterburner.

Other Noteworthy Features of the J-36

This fighter combines fly-by-wire technology with a tailless delta-wing design that provides it with an extremely low radar signature, high stability, and advanced maneuverability at high speeds. Moreover, the warbird is equipped with computer-controlled flight surfaces and reduced drag, ensuring fuel efficiency and extended operational range.

Reportedly, it has an exceptionally large wingspan for a fighter jet, with a wingspan of 24 meters (78.74 feet); for the basis of comparison and contrast, the J-20 has a wingspan of 13.01 meters (42.68 feet), and the F-35 has a wingspan of 11 meters (35 feet).

Meanwhile, fuselage length is estimated at 22.5 meters (73.81 feet).

About the Author: Christian D. Orr, Defense Expert

Christian D. Orr is a Senior Defense Editor. He is a former Air Force Security Forces officer, Federal law enforcement officer, and private military contractor (with assignments worked in Iraq, the United Arab Emirates, Kosovo, Japan, Germany, and the Pentagon). Chris holds a B.A. in International Relations from the University of Southern California (USC) and an M.A. in Intelligence Studies (concentration in Terrorism Studies) from American Military University (AMU).