Raytheon concept for an air-breathing hypersonic cruise missile. (Raytheon)

UPDATED To Include Raytheon Statement. WASHINGTON: A Raytheon-built hypersonic cruise missile built under the Defense Department’s classified Hypersonic Air-Breathing Weapons Concept (HAWC) program successfully completed its first flight last week, the department revealed today.

“The HAWC free flight test was a successful demonstration of the capabilities that will make hypersonic cruise missiles a highly effective tool for our warfighters,” said Andrew (Tippy) Knoedler, HAWC program manager in DARPA’s Tactical Technology Office, in a press release this afternoon. “This brings us one step closer to transitioning HAWC to a program of record that offers next generation capability to the U.S military.”

UPDATE BEGINS “This is a history-making moment, and this success paves the way for an affordable, long-range hypersonic system in the near term to strengthen national security,” said Colin Whelan, vice president of advanced technology at Raytheon Missiles & Defense, in a statement. “This test proves we can deliver the first operational hypersonic scramjet, providing a significant increase in warfighting capabilities.” UPDATE ENDS

 

DARPA is running the HAWC project, which is aimed at fleshing out the underlying technologies required for scramjet-powered hypersonic cruise missiles. The Air Force is the advanced research agency’s transition partner for the project.

The first HAWC free-flight test was initially planned for late last year, following a successful Sept. 2020 captive carry test for both the Raytheon missile and a competing variant built by Lockheed Martin. That test, as first reported by Air Force Magazine, reportedly would have involved the Lockheed Martin missile, but was scrubbed due to problems.

During last week’s test, the DARPA press release said, the scramjet engine built by Northrop Grumman “compressed incoming air mixed with its hydrocarbon fuel and began igniting that fast-moving airflow mixture, propelling the cruiser at a speed greater than Mach 5 (five times the speed of sound).”

Scramjets take in oxygen from the atmosphere, rather carrying bulky oxygen tanks — as boost-glide rocket boosters do. Thus, air-breathing hypersonic missiles can be made smaller, to be carried by fighter jets rather than big, heavy bombers.

But flying at greater than Mach 5 (scramjet powered cruise missiles are estimated to be able to fly at about Mach 7) through the atmosphere also creates friction, heating up an air-breathing hypersonic weapon in ways a boost-glide design, which spends most of its time in a near-vacuum, does not. Scramjets remain experimental, as do many of the materials designed to keep temperatures on the missile down so that avionics and other subsystems can function.

DARPA’s press release said the goals of the mission were “vehicle integration and release sequence, safe separation from the launch aircraft, booster ignition and boost, booster separation and engine ignition, and cruise.” The agency stated that all “primary test objectives were met.”

DARPA requested $10 million for HAWC in fiscal year 2022, but the agency has not released a projected date for transitioning the project to the Air Force.

“The HAWC flight test data will help validate affordable system designs and manufacturing approaches that will field air-breathing hypersonic missiles to our warfighters in the near future,” the agency’s press release said.

Other Efforts

Meanwhile, the Air Force is working on another highly classified air-launched hypersonic cruise missile called the Hypersonic Attack Cruise Missile (HACM) — itself based on the research being done under the HAWC project. The service asked for $190.1 million for the effort in its 2022 budget request.

A third effort, called Project Mayhem, is also underway, but very little is known about the program, which is technically known as the Expendable Hypersonic Air-Breathing Multi-Mission Demonstrator Program.

Those programs are significantly less mature, however, than the Air Force’s major hypersonic R&D effort, the AGM-183A Air-Launched Rapid Response Weapon (ARRW), also being developed in tandem with DARPA.

ARRW (pronounced arrow) is a hypersonic glide vehicle designed to be carried by a B-52 bomber. The Air Force is seeking about $161 million in fiscal 2022 to produce the first 12 ARRW missiles, on top of some $238.3 million in R&D funds. Lockheed Martin Space is the prime contractor.

So far, that program has been a bit of a bust. ARRW’s failed its first flight test in April. The second booster flight test, on July 28, also failed because the engine failed to ignite, and the service still hasn’t released any information on what caused the problem. Nonetheless, the service — for the moment, anyway — remains wedded to beginning production of the missile in 2022.

However, new Air Force Secretary Frank Kendall last week during the annual Air Force Association conference presaged a potential shake up in the service’s overarching plans for hypersonic missiles. Kendall raised concerns both about the maturity of the service’s operational concepts for such high-speed, long-range and highly maneuverable missiles, as well as its acquisition strategy.