China has just marked the start of a slew of new experiments to be conducted in the nation’s newest wind tunnel, and one of the key applications of the cutting-edge facility is to make the People’s Liberation Army’s next-generation fighter jets more stealthy and fuel-efficient.

The new tool for aerodynamic research, a continuous transonic wind tunnel built by the state-owned Aviation Industry Corp of China (AVIC), features a formidable size: a volume of 17,000 cubic meters weighing a cool 6,000 metric tons.

Codenamed the FL-62, the wind tunnel is able to provide a stable wind field for precise measurements to cut short the design time for a new aircraft.

A wind tunnel consists of a tubular passage with the object under test mounted in the middle. Air is made to move past the object by a powerful fan system or other means. The test object, often called a wind-tunnel model, is instrumented with suitable sensors to measure aerodynamic forces, pressure distribution, or other aerodynamic-related characteristics. A wind tunnel is vital to simulate the airflow around an aircraft before it conducts a real flight test.

The advances in computational fluid dynamics (CFD) modeling on high-speed supercomputers has reduced the demand for wind-tunnel testing but the modeling results are still not completely reliable and wind tunnels are used to verify CFD predictions.

The AVIC did not specify the exact location of the FL-62 wind tunnel but previous reports by Chinese papers said the nation was constructing a “wind-tunnel cluster” in the city of Mianyang in the southwestern province of Sichuan.

The AVIC said in a press release that the FL-62 would help determine the design of China’s sixth-generation fighter jets.

The Global Times reported that the new fighters would incorporate artificial intelligence to command multiple unmanned aerial vehicles and would be fitted with lasers and high-power microwaves weapons. They will be the new cachet of the nation’s capabilities in warplane development.

The fifth-generation J-20, which has just entered mass production, is the most advanced fighter currently in service with the PLA Air Force.

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The massive hypersonic wind tunnel inaugurated at the Chinese Academy of Sciences is being touted by state media as another milestone of China’s research and development of cutting-edge facilities. Photo: CCTV screen grab

Hypersonic wind tunnels can also help find design flaws in China’s planes and ballistic missiles and simulate space vehicles re-entering the atmosphere.

State broadcaster China Central Television also revealed in March that China was wrapping up construction of the world’s most high-speed wind tunnel to test a future hypersonic spaceplane theoretically capable of a whopping Mach 25, or 30,625km/h, 25 times the speed of sound.

The 265-meter hypersonic wind tunnel tailor-made to test aircraft, arguably one of the largest in its category globally, is now taking shape at the Chinese Academy of Sciences’ Laboratory of High Temperature Gas Dynamics.