Following a failed flight test in March of 2023, the US Air Force announced it would cancel plans to procure the AGM-183A hypersonic missile. A month later the service seemingly reversed course, announcing it would decide at a later date whether or not to acquire the weapon.
The Air-launched Rapid Response Weapon (ARRW; pronounced: ‘Arrow’) program aims to develop an air-launched hypersonic glide vehicle (HGV) prototype capable of sustained flight speeds between Mach 6.5 and Mach 8, and with an operational range of circa 1,600 km. The United States Air Force (USAF) has designated the objective Air-to-Ground Missile weapon system as the AGM-183A. The weapon is intended to be launched at high altitude by B-52 and B-1 bombers and be deployed against highly defended targets. The B-52 could carry a total of four missiles externally, while the B-1 could accommodate 31 missiles through combined internal and underwing carriage. A possible launch via F-15EX fighters has also been proposed, although the weapon’s size would probably preclude such deployment.
The complete AGM-183 consists of an all-up-round (AUR) integrating the HGV with a booster rocket. Like all HGVs, the ARRW does not have a conventional propulsion system. Instead, the booster rocket ignites after the weapon system is released by the bomber, and accelerates the AGM-183A to hypersonic speeds. After the booster burns out, the protective nose cone separates to release the inert wedge-shaped HGV which continues to glide toward its target at hypersonic speed. According to some sources the HGV could reach speeds up to Mach 20, and would destroy the target through the kinetic energy released by the high-speed impact.
Testing Programme
ARRW was initiated as a rapid prototyping project aimed at fielding an operational capability as quickly as possible in response to an urgent need – in this case Russian and Chinese advances in hypersonic weaponry which need to be balanced quickly. USAF awarded Lockheed Martin an initial USD 480 M ARRW design contract in May 2018. This was followed in December 2019 by a USD 989 M contract modification for the ARRW critical design review, test and production readiness support. Successful airborne captive carry tests of the HGV beneath the wing of a B-52 bomber were conducted in 2019 and 2020.
Launch- and flight-testing of the ARRW booster rocket began in April 2021. All three flight tests attempted in that year failed, each time for a different reason, leading Congress to cut the 2022 program budget in half. The final two booster tests, conducted in 2022, were successful. This opened the door for flight tests of the full operational prototype, consisting of the complete All Up Round including both the hypersonic glide vehicle and the booster rocket. The first of four planned AUR flight tests took place on 9 December 2022. Following release from the B-52, the missile accelerated to hypersonic speeds, completed the planned flight path, and struck the offshore target area, thereby meeting all test objectives. However, the second operational prototype test, conducted on 13 March 2023, was declared a failure. The comprehensive test was designed to evaluate the AGM-183A’s ‘end-to-end performance’ from captive carry through launch, booster ignition, shroud separation, and hypersonic body glide to impact. Citing operational security, USAF declined to provide details of the failure. Instead, the service announced that – although several test objectives had been met – the test was unsuccessful overall because vital data was either not collected or lost.
Wrapping Up…
On 29 March 2023 – 16 days after the last failed test – USAF seemed to announce the impending cancellation of the AGM-183 program. Andrew Hunter, the Assistant Secretary of the Air Force for Acquisition, Technology and Logistics, informed Congress that USAF “does not currently intend to pursue follow-on procurement of ARRW once the prototyping program concludes.” He added that USAF did wish to complete the two remaining planned AUR flight tests in order to collect data which could flow into future hypersonic development programs. To support the final tests and evaluation, USAF is requesting USD 150 M in funding for Fiscal Year (FY) 2024. According to concurrent USAF statements, remaining program elements planned in 2024 include “complete contract closeout, finalise documentation and analysis, and activities to support the leave-behind capability.” The “leave-behind capability” refers to an unspecified number of production-representative weapons which could be used for further research or, hypothetically, even be deployed in combat.
…Or Not?
Then, on 28 April 2023, Air Force Secretary Frank Kendall seemed to contradict Hunter. In testimony before Congress, Kendall stated that a final decision regarding AGM-183A procurement had not been made. Rather, the service would await the conclusion of the complete AUR testing cycle and conduct a comprehensive evaluation of the results before committing to either procurement or termination. “We haven’t stopped on ARRW. We still have funds to complete the test program. And we’ll reserve judgment until we see how that does and we’ll look at our priorities going forward,” Kendall told the House Armed Services Committee. He added that, if the final test flights are successful, “we’ll revisit it … as we build the [2025] budget and see what will be done in the future.”
A USAF spokesperson later confirmed the position expressed by Kendall, stating that Hunter had merely been referencing the fact that the Pentagon was not requesting procurement funding for FY 2024. The spokesperson added that – if the testing and system production readiness review demonstrate the AGM-183A’s operational utility – “the AF will [then] need to look at our weapons mix and see if ARRW falls within the requirements.”
However, closer inspection of the various official’s statements shows that there is no great contradiction between their respective positions. Kendall himself has frequently voiced dissatisfaction with the pace of the program. As recently as 28 March 2023 – one day before Andrew Hunter’s testimony – Kendall openly stated that USAF was more committed to its second air-launched hypersonic weapon program, the Hypersonic Attack Cruise Missile (HACM). The Air Force Secretary reiterated that sentiment in late April, stating “HACM, we think, offers the most potential to us at this point.” Kendall stated that HACM has demonstrated a “reasonably successful” development schedule to date and promises a “greater combat capability overall.” This statement of preference is in and of itself telling, as HACM is not expected to achieve operational utility before 2027, and purportedly will have only half the objective range of the AGM-183A. Kendall’s evaluation most likely reflects a conviction that ARRW is technologically too immature. The one major advantage of HACM is the fact that it could be carried by a greater variety of aircraft including US and allied tactical fighters, providing greater flexibility and deployment options.
Decision Time
Given the pattern of negative evaluations made by senior civilian USAF leadership in recent years, it would seem logical that the latest deferment of judgement regarding a procurement decision is primarily aimed at securing the funding to conclude the planned ARRW testing cycle, in order to flow the results into other research projects. Given past congressional cuts to programs which fail to perform in testing, the Pentagon must anticipate that funding for a scrapped program would be terminated. Congressman Ken Calvert, Chairman of the House Appropriations Committee defense subcommittee, hinted at this in a 28 March 2023 exchange with Kendall. “I don’t like to call it [research and development] welfare, but it seems to go on forever,” Calvert said.
In a speech delivered on 9 May 2023, Deputy Defense Secretary Kathleen Hicks gave the most recent indicator that the ARRW will not continue past the current testing cycle. Specifically referencing ARRW, Hicks underscored the need to be vocal about learning from potentially unsuccessful experiments. “Some tests worked. Some tests didn’t. But even then, we still learned a lot of useful things from ARRW — which we’re applying to the many other hypersonic missiles we’re developing and procuring across DoD. […] We have to embrace the fact that being truly innovative requires a willingness to fail, and learn from failure, and try again.”
Sidney E. Dean