A hypersonic hiccup for the US Air Force

A key multi-million dollar American hypersonic missile project looks doomed after another unsuccessful flight test. At a time when Russia has been firing hypersonic missiles against Ukraine, the setback for the US military was confirmed by Frank Kendall, the Pentagon’s air force secretary. The air-launched rapid response weapon (ARRW), launched from a B-52H strategic bomber and capable of reaching in excess of Mach 5 - five times the speed of sound – was intended to be the US Air Force’s primary hypersonic weapon. However, following the failed test last week, Kendall indicated ARRW’s fate might be sealed and research efforts would be switched to a second “more promising” programme called hypersonic attack cruise missile (HACM). “We see a definite role for the HACM concept. It’s compatible with more of our aircraft, and it will give us more combat capability overall. So we’re more committed to HACM at this point in time than we are to ARRW,” he told the House appropriations defence subcommittee. Hypersonic missiles which could ultimately reach speeds of up to Mach 20 have generated an intensive arms race between the US, Russia and China. Flying faster than a mile a second and manoeuvring throughout the flight, hypersonic missiles test the limits of weapons development. Russia is the first of the rival great powers to deploy an operational system. The Kinzhal hypersonic missile was first used in combat against Ukraine on March 19 last year. It was unveiled by President Putin five years ago. The Pentagon’s ARRW missile potentially has greater capability than the Kinzhal. In December, a full assessment of ARRW was carried out and the results were optimistic, despite initial test failures. In the recently released defence budget for 2024, the air force requested $150 million to continue development. But if the next planned tests fail, the programme may be scrapped. The budget for the alternative HACM system allows for $380 million to be spent on development in 2024. HACM is a scramjet-powered hypersonic air-launched cruise missile which will be fitted initially to the F-15E Strike Eagle fighter aircraft. Assuming flight tests go well, the HACM capability could be operational by 2027. The US Army and US Navy are working together to produce a long-range hypersonic missile. The navy version will be put on the Zumwalt-class guided-missile destroyer.