China building world's fastest hypersonic wind tunnel

China is building the world's fastest hypersonic wind tunnel to develop spaceplanes, official media has reported.

"The 265-metre-long tunnel can be used to test hypersonic aircraft that can travel at speeds of up to Mach 25 (30,625 kph), 25 times the speed of sound," Han Guilai, a researcher with China's State Key Laboratory of High Temperature Gas Dynamics of the Chinese Academy of Sciences (CAS), told China Central Television over the weekend.

Han said the current wind tunnel could simulate flights ranging from Mach 5 to 9. Researchers from CAS in Beijing have successfully tested one hypersonic plane in a wind tunnel at such speeds, state-run Xinhua news agency reported.

The research was published in the journal 'Science China: Physics, Mechanics & Astronomy' in February. It unveiled the 'I Plane' model, which is capable of transporting people and payloads from Beijing to New York within two hours, beating any commercial airline flight.

Wind tunnels move air around objects, making it seem like the objects are really flying. Spacecraft engineers use them to test ideas for various spacecraft designs. Long after the design work is finished, wind tunnels help make spacecraft better and safer.

The new wind tunnel will help China take the lead in wind tunnel building, though competition from other countries is still fierce, Han said.

"The new tunnel will aid the engineering application of hypersonic technology by duplicating the environment of extreme hypersonic flights. Once issues are discovered during these ground tests, they will be ironed out before test flights begin," Han said.