The Missile Defense Agency (MDA) is fast-tracking design and concept work on an innovative technology intended to destroy hypersonic weapons moving at five times the speed of sound along the boundary of the earth’s atmosphere. 

The Glide Phase Interceptor (GPI) program, now moving into a new developmental phase, is a Missile Defense Agency effort which just awarded development deals to Raytheon, Northrop Grumman, and Lockheed. The concept, which will soon enter into digital design, engineering and prototyping phases, is based upon the ability to intercept attacking a hypersonic glide body during its glide phase of flight before it reenters the earth’s atmosphere. 

A hypersonic boost-glide weapon flies beyond the earth’s atmosphere to glide at hypersonic speeds before descending on its target. Just before the missile begins its high-speed descent is the best opportunity to intercept it.

“So when you're in the glide phase -- which is higher up from the terminal, right, where a hypersonic vehicle is likely in its most vulnerable phase -- that's actually a pretty tough environment to be in,” Navy Vice Adm. Jon Hill, Director, MDA told reporters earlier this year, according to a Pentagon transcript. “And you can't take an air defense weapon and operate it there nor can you take a space weapon like an SM-3 and operate there, it's just a different environment.”

Initial thoughts were that a GPI might not come to fruition until the 2030s, Hill said. But new data collected from live fires during experiments on ship-based Aegis radar models and ground systems have moved the schedule up. Prototypes of the interceptor will integrate with the Aegis ship-based combat system which connects missile radar with fire control, computing, ship-based command and control, and missile firing technology. 

The GPI is expected to fire from the Vertical Launch Systems on the decks of Navy warships. While many details related to potential technologies for the program in the areas of propulsion, guidance, or speed are unavailable for security reasons, it seems significant that there may be ways to track a hypersonic missile traveling between radar fields of view and then launch a kinetic interceptor quickly enough to destroy the weapon. 

Hill said that the MDA is now “maturing technologies” and working with industry to evolve “seekers and materials for operating” in that portion of the atmosphere, as well as exploring propulsion techniques to succeed in firing an interceptor capable of reaching and destroying an hypersonic weapon during its glide phase.

One reason why the possibility of intercepting a hypersonic weapon may become more realistic relates to an interesting technology called “launch on remote.” This means detection and tracking can take place somewhere farther way, and not necessarily on the ship. Advanced sensing and networking technologies may enable radar systems to find a hypersonic missile and relay details to the ship’s fire control and launch systems. 

Launch-on-remote became possible in recent years through upgrades to ship-integrated Aegis radar systems and networking developments, enabling dispersed assets to pass targeting information and other crucial data to shoot off interceptors.

“We found that we can close the fire control loop with an Aegis ship that has already proven queuing launch-on-remote and engage on remote capability,” Hill said. 

Kris Osborn is the defense editor for the National Interest. Osborn previously served at the Pentagon as a Highly Qualified Expert with the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Master's Degree in Comparative Literature from Columbia University.

Image: Reuters.