Australian, U.S. HIFiRE rocket achieves Mach 7.5

CANBERRA, Australia, May 18 (UPI) -- Australia and the United States have successfully fired an experimental rocket with a speed of more than seven times the speed of sound.

The rocket, which reached an apogee, or highest altitude, of about 172.7 miles, is part of a joint research program called HIFiRE, or Hypersonic International Flight Research Experimentation Program. It is being conducted by Australia's Defense Science and Technology Group and the U.S. Air Force Research Laboratory with Boeing and the University of Queensland providing expert technical design and analysis.

The aim of the program is to explore fundamental technologies critical for sustained hypersonic flight, which is five times and more of the speed of sound.

"The success of this test launch takes us one step closer to the realization of hypersonic flight," said Dr. Alex Zelinsky, chief scientist of the Australian Department of Defense. "It is a game-changing technology identified in the 2016 Defense White Paper and could revolutionize global air travel, providing cost-effective access to space."

The experimental rocket was launched the Woomera Test Range in South Australia.

The Australian Department of Defense said the targeted speed achieved was Mach 7.5, or seven and a half times the speed of sound. The speed of sound in dry air at 68 degrees Fahrenheit is about 1,126 miles per second, or 768 miles per hour.