High-Speed Strike Weapon (HSSW)
ATK is developing the scramjet engine for the Hypersonic High-Speed Strike Weapon (HSSW) in response to the Department of Defense’s need for a rapid strike weapon.

The design for the HSSW uses ATK’s solid rocket motor capabilities to boost the weapon to Mach 4, where the scramjet engine kicks in to accelerate to speeds approaching Mach 5. The HSSW can be launched from bombers, fighter jets, submarines, and surface ships.

ATK is the world leader in the development of hypervelocity and air-breathing propulsion systems. In 2004, the X-43 hypersonic flight vehicle built by ATK for NASA set the world speed record for air-breathing powered flight at Mach 10 or nearly 7,000 miles per hour. ATK is also designing and developing scramjet propulsion engines for the X-51 Robust Scramjet program, a U.S. Air Force initiative to advance the state of the art for liquid hydrocarbon and hydrogen-fueled scramjet propulsion systems.