According to SCMP , China's new supersonic unmanned aerial vehicle (UAV) has a lift-to-drag ratio of 8.4 in subsonic flight. Although it is not very high, it is on par with the F-22 Raptor, the US military's most advanced fighter jet.
The lift-to-drag ratio is an important parameter for measuring aerodynamic performance. A higher value indicates a greater ability of the aircraft to resist gravity, allowing it to fly further.
China's supersonic UAV proves superior to the US F-22 Raptor during testing. (Photo: EPA-EPE)
Nearly 20 years after its introduction, the technology behind the F-22 Raptor remains a secret. William Oehlschlager, a senior aerospace engineer with the Federal Aviation Administration (FAA), said in a presentation at Virginia Tech that the F-22 can achieve a maximum lift-to-drag ratio of 8.4. However, the faster the aircraft flies, the greater the drag it encounters. At Mach 1.5, the F-22's lift-to-drag ratio drops to about 4.
Meanwhile, China's new hypersonic UAV can maintain a lift-to-drag ratio of more than 4 even when flying at speeds six times the speed of sound, showing superior aerodynamic efficiency compared to the F-22.
This performance allows UAVs to operate flexibly even in thin air conditions at high altitudes, posing a challenge to missile defense systems that rely on flight trajectory prediction.
"Previously, the aerodynamic parameters of China's hypersonic aircraft were mainly based on theoretical models. But this time the data was obtained from wind tunnel tests under real-world constraints," said Zhang Chenan, aerodynamics expert at the Institute of Mechanics of the Chinese Academy of Sciences.
The experimental results of the research team led by Mr. Zhang were published in the peer-reviewed Chinese academic journal Acta Mechanica Sinica on February 23.
Mr. Zhang's team did not reveal the model of the new UAV, but it bears a strong resemblance to the MD-22 hypersonic aircraft announced in 2019.
Developed by the Guangdong Aerospace Science and Industry Research Institute under the Institute of Mechanics, the MD-22 is a reusable hypersonic flight technology testbed for near-space applications, offering ultra-long range and high maneuverability.
This unmanned aerial vehicle can transport a payload of 600 kg at speeds of up to Mach 7 over a distance of 8,000 km, equivalent to the distance between mainland China and the continental United States.
Weighing just 4 tons, the MD-22 can be propelled by a turbofan engine to take off from an airport runway or launched vertically from a rocket launch pad. It can withstand an overload of up to 6 times the force of gravity when performing high-speed turns.
The new UAV model described by Zhang's team is more than 12 meters long with a wingspan of nearly 6 meters, significantly larger than the MD-22. However, its aerodynamic structure with three engine bays protruding from the tail is virtually unchanged.
Chinese scientists and engineers have overcome challenges related to lift-to-drag ratio, stability, thermal protection and payload integration, achieving “engineering practicality” in the technology, the report said. Their future goals are to reduce costs, improve reliability and radar stealth performance to “transform from feature to practical use in stages.”
Aerodynamic design plays a crucial role in the success or failure of a hypersonic vehicle project. The US HTV-2 hypersonic aircraft crashed twice due to instability during high-speed flight, forcing NASA to halt the project. However, China has continued to support research and development in this field, and has conducted many test flights over the years.
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