Ar-Rehman: July 2025

6th-Gen fighters are under development phase

Known as Tempest in the UK, which began the effort, the supersonic Global Combat Air Programme fighter is not only the first fighter to be built in Britain in 40 years, it's one of the first of a whole new class of combat aircraft with an advanced design incorporating a raft of new technologies and capabilities that verge of science fiction. One of the world's first sixth-generation fighters has moved closer to its first flight, as BAE Systems unveils the prototype Combat Air Flying Demonstrator, now under construction for the Global Combat Air Programme by Britain, Italy and Japan. Expected to become operational by 2035 as a replacement for the Typhoon Eurofighter and a major advance on the F-35 Lightning II, the first major step in the program is to complete the demonstrator aircraft for its first flight in 2027. Its purpose is to help iron out any bugs in the design and develop the processes needed to manufacture the final aircraft.

On the other side of the world, China is reportedly developing a 6th-generation fighter J-36 Fighter. 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 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 China, 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 war birds 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). Following are the some of the important points of J-36:-

The Chengdu J-36 boasts a stunning top speed of Mach 2.5.

This would make it significantly faster than America’s premier stealth fighters, the F-22 Raptor and F-35 Lightning II, and put it on par with the legendary F-15 Eagle.

The secretive J-36 is described as a tailless delta-wing design with an exceptionally large wingspan and an unusual, powerful “tri-engine” configuration.

If the reports are accurate, the J-36 represents a major leap in China’s aerospace industry and a formidable new threat in the race for air dominance.

Of course, with this fighter being very new, sources vary on this data point.

For Tempest until now, we've had to rely on artist's concepts and mock ups of the final Tempest fighter, but the release of the admittedly unadorned rendering of the demonstrator and of the actual airframe on the factory floor provide the first concrete idea of the finished product. According to BAE Systems, by structural weight the demonstrator is already two-thirds completed, including the fuselage and wings. It's the product of a tranche of new digital manufacturing techniques which include 3D printing for rapid prototyping and simplification of components, digital twins, model-based systems engineering virtual simulations and cobotics, which are robots designed to work closely and safely with human workers. Even though the demonstrator has yet to be completed, test pilots from BAE Systems, Rolls-Royce and the RAF have already flown over 300 simulated hours. This has allowed for rapid improvements of the flight controls by putting them and the simulated aircraft through complex flight operations.

Along with these improvements, the Tempest boasts a modular design for quick upgrades, integrated AI and machine learning systems, Loyal Wingman controls which turn the fighter into a command and control centre for swarm drones, new stealth technologies and a virtual cockpit that can be easily reconfigured to suit a particular mission or task. In addition to identifying manufacturing problems, the program also deals with a new high-speed pilot ejector seat and a new Rolls-Royce jet engine. The expected end result will be a pilot-optional fighter with twice the payload of the F-35A and enough range to carry out transatlantic flights without refuelling for an engine which has enough surplus electrical generating capacity to handle energy weapons and hypersonic launchers. "This significant and challenging project will deliver the UK’s first crewed combat demonstrator aircraft in four decades," said Tony Godbold, Future Combat Air Systems Delivery Director, BAE Systems. The program is accelerating the development of advanced design approaches and manufacturing techniques, helping to sharpen the UK’s industrial edge and deliver benefits beyond the production of the aircraft. "As well as developing a unique aircraft, we’re building the technical foundations, workforce readiness and digital maturity essential to deliver the next generation of combat air capability."

If reported Mach 2.5 figure is correct for J-36, it 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. It 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 Mach 2.5 figure is 30 December, 2024 article by Dan Arkin of Israel Defence 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. We can reasonably speculate that the power plant 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.

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