First Release Of USAF’s New HACM Hypersonic Cruise Missile Has Happened Over Australian Range

The U.S. Air Force’s scramjet-powered Hypersonic Attack Cruise Missile (HACM) has finally reached the flight test phase, with at least one “release” having been carried out so far over a range in Australia. HACM has suffered significant delays, and the Air Force has taken the risky step of scaling back overall testing plans to try to keep the program on schedule. The stated goal is to be able to make a decision to start rapidly acquiring HACMs in 2027.

The Air Force has been working on HACM in cooperation with the Royal Australian Air Force (RAAF). The program has been conducted, in part, under the broader umbrella of the U.S.-Australian Southern Cross Integrated Flight Research Experiment (SCIFiRE). The Defense Advanced Research Projects Agency’s (DARPA) Hypersonic Air-breathing Weapon Concept (HAWC) project also fed into HACM. Raytheon (now formally RTX), in cooperation with Northrop Grumman, was chosen to develop the missile in 2022. The weapon has reportedly been designated AHM-4A in a new branch of the U.S. military’s joint service nomenclature system for aircraft and missiles.

A rendering DARPA put out during the preceding Hypersonic Air-breathing Weapon Concept (HAWC) effort. DARPA

“The U.S. Air Force, in partnership with Australia, has conducted a flight test of the Hypersonic Attack Cruise Missile (HACM) as part of our continuous work to advance long-range strike capabilities,” an Air Force spokesperson confirmed to TWZ today. “This effort is part of the Southern Cross Integrated Flight Research Experiment (SCIFiRE), a collaborative agreement built on more than 15 years of partnership between our two nations.”

“Leveraging this enduring alliance, the Royal Australian Air Force executed the release of a HACM flight test unit over a designated Australian test range, gathering crucial data to advance the program’s objectives,” the spokesperson added. “The flight was the culmination of an extensive series of tests designed to measure the missile’s performance under realistic flight conditions.”

The spokesperson did not name the test range where the “release” was conducted or say when that occurred. Whether the missile flew under its own power for any amount of time after release is unknown. What aircraft was used to carry the missile aloft is also not known. TWZ has reached out for more information.

The Air Force did say previously that it planned to conduct HACM launches in Australia. The expectation has long been that this would be done at the country’s sprawling Woomera Test Range, which provides an ideal location for extended-range flight testing activities in general. The U.S. and Australia have partnered on other hypersonic testing at Woomera in the past, as seen in the video below. The remote inland location of the range complex makes it well suited for conducting more sensitive tests away from prying eyes, as well.

The Government Accountability Office (GAO), a Congressional watchdog, has also reported in the past that RAAF F/A-18F Super Hornets would be used to conduct at least some of the HACM test launches. This would fit with today’s statement from the U.S. Air Force saying that it was the RAAF that “executed the release.” The Air Force’s initial launch platform is the F-15E Strike Eagle, though others are expected to follow.

A pair of RAAF F/A-18F Super Hornets. RAAF

To date, neither the Air Force nor Raytheon has released a confirmed picture or rendering of HACM. In 2023, the Air Force did release a picture, seen below, showing an air-breathing hypersonic cruise missile test article related to either HACM or the preceding HAWC effort.

USAF

“The missile consists of two stages, a rocket booster and a scramjet cruiser, which separates from the booster and eventually dives toward its target,” according to GAO. Scramjets do not function effectively at lower speeds, and designs powered by them require some form of initial boost to a high Mach velocity. Hypersonic speed is generally defined as anything above Mach 5, but what HACM’s peak speed might be is unknown.

Two-stage air-breathing missile-like hypersonic vehicle designs have been tested on several occasions in the past. This includes Boeing’s scramjet-powered X-51 Waverider and HyFly 2 hypersonic test vehicles, among others. The X-51 (as its name indicates) and HyFly 2 also notably had so-called ‘waverider’ configurations designed to ‘skip’ on the shockwaves generated during high-speed flight to help provide additional lift. Whether HACM might also use this principle is not known.

It’s also worth noting here that Castelion’s Blackbeard hypersonic missile also has a two-stage configuration. It remains unconfirmed whether or not the second stage of that weapon is powered, but it does not appear to be an air-breathing design either way. Castelion is currently developing an air-launched version of Blackbeard for the U.S. Navy, which is also in flight testing now, as well as a ground-launched type for the U.S. Army. You can read more about that missile here.

Coming soon to a theater near you…BLACKBEARD!<a href="https://x.com/USPACOM?ref_src=twsrc%5Etfw" rel

Source: www.twz.com — article syndicated from the publisher’s feed; all rights remain with the original publisher.