US, Australia conclude secretive hypersonic flight series

The United States and Australia have concluded a series of hypersonic test flights at the Woomera test range in South Australia.

The tests were conducted under the auspices of the Hypersonic International Flight Research Experimentation (HiFIRE) programme, says Australia's Department of Defence in a statement.

In the statement, defence minister Marise Payne congratulated Canberra's Defence Science and Technology Group (DST) and the US Air Force Research Laboratory (AFRL) "on another successful hypersonic flight at Woomera test range."

She said that the tests have achieved "significant milestones, including design assembly, and pre-flight testing of the hypersonic vehicles and design of complex avionics and control systems."

She said Canberra and Washington DC are drafting plans for future hypersonic work.

The statement also thanked Boeing, BAE Systems, and the University of Queensland as partners on the programme.

FlightGlobal requested details from the parties involved in the last tests, such as the speeds achieved and distances travelled, but this information was not forthcoming.

Previous HiFIRE launches have achieved speeds of Mach 7.5. The tests involve the ballistic launch of a vehicle that includes hypersonic inlet, a scramjet cumbustor (through which air flows at supersonic speeds) and a nozzle. It also carries instruments to transmit test data to researchers on the ground.

Boeing declined to comment on the launch, but BAE Systems Australia issued a statement.

"We were pleased to support the DST with the successful flight trial; the most complex of all HIFiRE flights conducted to date, to further the fundamental scientific understanding of hypersonic flight… This flight trial is a significant step forward in proving this technology and enhancing our collective understanding of how it could be employed across a range of applications."

Hypersonic speeds are defined as above M5.5. One clear application for the technology is Washington's Prompt Global Strike (PGS) initiative, which aims to develop a hypersonic, precision-guided conventional weapon that can deploy anywhere in the world within one hour.