The development of hypersonic weapons has become and continues to be one of the U.S. military’s top priorities. A recent contract award shows that the U.S. Navy is spending millions to keep developing a submarine-launched type that might eventually arm its future Columbia-class ballistic missile submarines. Now, the U.S. Air Force has announced that an air-launched hypersonic test bed it is developing in cooperation with NASA to support various projects will become the latest of America’s research and development “X-planes.” On Oct. 1, 2018, the Pentagon announced that the Navy had awarded the Charles Stark Draper Laboratory in Massachusetts a contract worth more than $13 million for various services in support of actual hypersonic weapon flight tests. Then, on Oct. 4, 2018, the Air Force Research Laboratory (AFRL) revealed that space launch firm Generation Orbit’s GOLauncher 1 (GO-1) hypersonic vehicle would now be known as the X-60A.

The full contracting notice for the Navy’s deal with Draper Labs is as follows:

“The Charles Stark Draper Laboratory, Cambridge, Massachusetts, is awarded a $13,380,171 cost-plus-fixed-fee contract to provide research into the applications of technologies to meet guidance requirements for operations on the Common Missile Compartment for the U.S. Columbia-class program and the United Kingdom Dreadnought-class program; provide specialized technical knowledge and support for the hypersonic guidance, navigation and control application; provide technical and engineering services to support the Guidance, Navigation and Control system that will support the Navy’s hypersonic flight experiments. Work will be performed in Cambridge, Massachusetts (81 percent); and El Segundo, California (19 percent), with an expected completion date of Sept. 30, 2019. Subject to the availability of funds, fiscal 2019 research, development, test, and evaluation funds in the amount of $13,380,171 will be obligated. No funds will expire at the end of the current fiscal year. This contract was a sole source acquisition pursuant to 10 U.S. Code 2304(c)(1)&(4). Strategic Systems Programs, Washington, District of Columbia, is the contracting activity (N00030-19-C-0001).”

The announcement does not specify what system Draper Labs, a non-profit research and development organization, will be working on. The basic description, though, sounds very similar to a submarine-launched hypersonic boost-glide vehicle that the Navy said it tested for the first time in 2017. Boost-glide vehicles are unpowered and typically use a ballistic missile to get to the appropriate speed and altitude. Pictures and video recently appeared to show researchers in China using a test apparatus slung beneath a high-altitude balloon for this purpose. Air-breathing hypersonic vehicles also require some sort of booster initially to get going fast enough for a high-speed jet engine, such as a ramjet, to take over. The Navy's test last year, officially known as the Intermediate-Range Conventional Prompt Strike Flight Experiment-1 (CPS FE-1), involved an Ohio-class ballistic missile submarine. The Navy’s Strategic Systems Program (SSP) office also oversaw that event, which took place at the Pacific Missile Range Facility in Hawaii.

USN An artist's conception of the future USS Columbia.

The launch proved that “the first conventional prompt strike missile for the United States Navy in the form factor that would eventually, could eventually be utilized if leadership chooses to do so in an Ohio-class tube,” U.S. Navy Vice Admiral Terry Benedict, director of SSP, said afterward. The contract with Draper Labs would seem to suggest that the Navy’s main goal is eventually integrating this weapon with the Columbia-class. Since those submarines will have the same Common Missile Compartment missile launch tube architecture as the United Kingdom’s future Dreadnought-class ballistic missile submarines, it is possible that the U.S. military could share the design with the British government, as well. Though not mentioned in the contracting notice, the individual tubes in the Common Missile Compartment are also the same basic size and shape as the ones in the Virginia Payload Module, which will go into the future Block V Virginia-class attack submarines, leaving open the possibility that they too may be able to use this weapon in the future.

USN A briefing slide from 2014, when the Columbia-class was still known simply as the "Ohio Replacement," showing the plan for the Common Missile Compartments, each of which contains a "quad-pack" of four missile launch tubes.

Of course, the U.S. military acknowledges that there is still much work to be done to fully understand that hypersonic vehicles will and won’t be able to do. Experiments continue simply to help identify materials that can withstand the heat and strain of sustained flight at five times the speed of sound or more, as well as advanced air-breathing jet engines that can handle that stress and keep the vehicle at a sustained speed. That’s where experimental systems such as the X-60A come into play. “The X-60A is like a flying wind tunnel to capture data that complements our current ground test capability,” U.S. Air Force Colonel Colin Tucker, the military deputy in the office of the Deputy Assistant Secretary of the Air Force for Science, Technology, and Engineering, said in a press release on Oct. 4, 2018. “It enables faster development of both our current hypersonic weapon rapid prototypes and evolving future systems.”

Generation Orbit An artists conception of the X-60A speeding away from its Learjet 35 launch aircraft.