The US Air Force has test-flown the almost-canceled AGM-183A Air-Launched Rapid Response Weapon (ARRW) in late February 2024 in a gainful bid to collect critical data related to hypersonic weapons. The Department of Defense is continuing the remaining tests, such as this, for a truly valuable look at how these Mach 5+ weapons are performing.
As far as clues on the upcoming test, some could be seen on social media and official Air Force sources over the weekend. The Defense Visual Information Service released photos of a live ARRW missile verge launched into action from a B-52H Stratofortress heavy strategic bomber at Andersen Air Force Base on the U.S. territory of Guam in the Pacific. Images generally similar to the view were taken at Edwards Air Force Base in 2023 ahead of a similar test.
Even more solid evidence about the incoming test was patched together by one Twitter user, who noticed several Notices to Airmen (NOTAMs) and Navigation Warnings (NAVWARNs) in the surrounding area of Kwajalein Atoll. These served to warn civilian aircraft and marine traffic from encroaching on certain areas, projected travel lanes laid out by the missile from its launch point to Kwajalein Atoll, and the location of aircraft used for special monitoring purposes.
Kwajalein Atoll, a US government missile test site in the Marshall Islands, supported atmospheric nuclear testing in the 1950s and now is home to tests of various missiles, particularly the Minuteman III intercontinental ballistic missiles launched from Vandenberg Air For Base in California.
The AGM-183A ARRW was developed as a hypervelocity, conventional missile for the rapid defeat of mobile and time-sensitive targets. It was one of several hypersonic missile programs initiated by the U.S. government following publicized Russian and Chinese developments in the mid-2010s. In 2018, according to Flight Global, the projectile was to be capable of speeds as high as Mach 20, or 15,345 mph.
However, the ARRW program suffered from developmental problems and failures in some of the tests, culminating in a cancellation in 2023. Despite this setback, the Air Force decided to move forward with the final two tests and launch the remaining developmental missiles to yield valuable data on hypersonic flight, a relatively under-researched field.
While hypersonic flight was first achieved in the late 1950s and modern ballistic missiles re-enter the atmosphere at Mach 18, the new generation of hypersonic weapons operates entirely within the atmosphere at high Mach numbers, which predisposes them to extreme levels of friction and pressure, previously not well understood.
Following the cancellation of ARRW, the Air Force shifted its focus to the Hypersonic Attack Cruise Missile (HACM). In 2023, Air Force Secretary Frank Kendall noted that HACM was “compatible with more of our aircraft and it will give us more combat capability overall” compared to ARRW. As a smaller missile, HACM can be carried by fighter jets, while the larger ARRW can only be carried by bombers. This size difference also suggests that a bomber can carry more HACMs than ARRWs, enabling a single aircraft to engage more targets during wartime.