The Space Tracking and Surveillance System (STSS) demonstration satellites, built and operated by Northrop Grumman [NOC], contributed to a successful sea-based Aegis missile defense test April 15 by acquiring, after being cued remotely, a target missile during the midcourse phase of its flight, according to a company statement. Sensor payloads onboard each satellite were designed and built by Raytheon [RTN].

STSS demonstrators tracked an intermediate range ballistic missile (IRBM)–from midcourse to termination, according to the Missile Defense Agency (MDA). The target was intercepted when an SM-3 Block 1A missile released its kinetic warhead, hitting and destroying the IRBM, MDA said.

“This event showed the flexibility of the STSS satellites. They were cued remotely by forward-based radar in the Command, Control, Battle Management and Communications system, which is a key capability for a future operational constellation,” said Doug Young, vice president, missile defense and warning for Northrop Grumman’s Aerospace Systems sector.

“The event also provided significant risk reduction for a follow-on, operational system. It closely emulated a large part of the communication chain that would be used in an operational engagement,” Young added.

The IRBM was launched from the Reagan Test Site located on Kwajalein Atoll in the Republic of the Marshall Islands. A forward-based AN/TPY-2, X-band, transportable radar located on Wake Island detected and tracked the missile. The radar sent trajectory information to the Command, Control, Battle Management and Communications system, which processed and transmitted remote target data to an Aegis destroyer, the USS O’Kane (DDG-77). The destroyer developed a fire control solution and launched an SM-3 missile about 11 minutes after the target was launched, according to MDA.