WASHINGTON — Air Force Secretary Frank Kendall said Wednesday he is more bullish about the future of the AGM-183A Air-Launched Rapid Response Weapon after two recent flight test successes — but the key hypersonic program has not yet proven itself.

Lawmakers earlier this year pulled almost $161 million in procurement funding the Pentagon requested to buy ARRW weapons in 2022, citing testing failures and delays that had extended the program’s schedule. In 2021, three attempts to test launch ARRW all ended in failure.

After that funding was withdrawn and half steered to hypersonic testing, Kendall said in March ARRW “still has to prove itself,” and the service must consider its future mix of weapons and how hypersonics might fit in.

This year, two successful ARRW tests bolstered the program, and Air Force acquisition chief Andrew Hunter said in July it is already more advanced than previous hypersonic programs.

Asked at Wednesday’s Defense News Conference in Arlington, Virginia, if this year’s testing successes signaled the program has proven itself, Kendall said no.

“We still have work to do on ARRW,” Kendall said. “I’m becoming more optimistic about it, as they have successes. But we haven’t finished the flight test program.”

Kendall said questions about the program’s cost-effectiveness, place in the Air Force’s hypersonic inventory, and how it might grow in the future still have yet to be answered.

Asked what more he wants to see from ARRW, Kendall said it needs to reach its full capability. The previous test phase that wrapped up with July’s successful test focused on the weapon’s booster, but its all-up-round, or full-system, testing will begin this fall.

Hypersonic weapons are able to fly at speeds greater than Mach 5 and are highly maneuverable, meaning they’re able to quickly change course midflight. This means they could be better able to penetrate defenses and harder to track and shoot down than conventional ballistic missiles that follow a predictable parabolic arc. Chinese and Russian investments in hypersonic technology and testing successes have increased pressure on the Pentagon to speed up progress on its own weapons.

Kendall declined to say whether the upcoming fiscal 2024 budget might seek to move funding back into procurement for ARRW.

He said the Air Force is interested in both air-breathing scramjet and boost glide variants for hypersonic weapons. Each type brings different capabilities, which would force adversaries to defend against multiple weapons, Kendall noted. The hope is this would give a potential enemy more problems than it would be able to handle.

However, cost remains a major challenge, Kendall said, adding that the Air Force shouldn’t “blindly embrace hypersonics as a panacea.”

“They’re a valuable tool to have in the toolbox,” he said. “We have to think about what targets they’re most appropriate for, where that increased cost and so on has value, and returns on investment.”

William LaPlante, the under secretary of defense for acquisition and sustainment, said later at the Defense News Conference it remains to be seen whether the defense industry will be able to produce hypersonic weapons at a significant rate.

“The old joke about hypersonics [is] hypersonics is the weapon of the future for 60 years,” LaPlante said. “We’ve never, ever produced and manufactured hypersonics, ever in this country. It’s been entirely [science and technology]. I ask this question all the time, and I get reassurance that they’re ready. But the proof will be in the pudding.”

Joe Gould contributed to this report.

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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