“It’s embracing a not-invented-here” attitude, Will Roper, the Assistant Secretary of the Air Force for Acquisition, Technology and Logistics, who was previously the head of the Pentagon's secretive Strategic Capabilities Office, told journalists in September 2018. The idea is about “just taking the fastest path to the goal line with the technology that exists.” Since the Navy faces the most challenges in developing a weapon that a ballistic missile submarine will be able to fire, it is in charge of developing the boost-glide vehicle itself, according to Aviation Week. On Oct. 1, 2018, the service awarded a contract worth more than $13 million to the Charles Stark Draper Laboratory in Massachusetts to support that work.

US Army A rendering of the AHW hypersonic boost-glide vehicle.

The vehicle itself is a conical design made of a composite of metals and other materials, including carbon fiber, which is derived from the one the Army had been developing for the AHW program. This, in turn, was based on a concept that Sandia National Laboratories had worked on between 1979 and 1985 known as the Sandia Winged Energetic Reentry Vehicle Experiment (SWERVE). Given this experience, Sandia will produce the actual prototypes and the Army will be responsible for flight testing them, sources told Aviation Week. Each of the three services involved in the program will use their own boosters for ground-, air-, and submarine-launched applications. Without any power of its own, a hypersonic boost glide vehicle requires some other means of getting it up to the appropriate altitude and speed, which has traditionally involved the use of ballistic missiles.

US Army A rocket booster carrying an Army's AHW hypersonic boost-glide vehicle blasts off during the first successful flight test of the system in 2011.

There remain few details about the exact size and capabilities of the new boost-glide vehicle. SWERVE was approximately 100 inches long and could reach a peak of Mach 12 before gliding along at a sustained Mach 8 for a full minute. The Army’s goal for AHW was also a sustained speed of around eight times the speed of sound that would allow the weapon to travel around 3,700 miles in just 35 minutes. The Pentagon had initially treated AHW as a less risky, more mature backup to the Defense Advanced Research Projects Agency’s (DARPA) more ambitious Force Application and Launch from Continental United States program, or FALCON. That project used half-cone boost-glide vehicle designs known as Hypersonic Test Vehicles (HTV) that held the promise of being faster, more maneuverable, and more accurate than those derived from SWERVE. These are important considerations for hypersonic vehicles, which by definition fly faster than Mach 5, and derive most of their benefits from that extreme speed and the ability to maneuver at those speeds. We at The War Zone have written in depth about the game-changing nature of these weapons, which open up the possibility of short- or no-notice strikes against time-sensitive and other critical targets, even at extreme ranges. That they can maneuver within the atmosphere along a less predictable flight path makes them even harder to spot and defend against compared to more traditional long-range weapons, such as ballistic missiles.

US Army An Army briefing slide describing the AHW program as of April 2012.