The US Air Force Space and Missile Systems Center has awarded a contract modification to perform the launch services for the wideband global SATCOM-4 (WGS-4) satellite.

Scheduled to launch between December 2011 and February 2012, the WGS-4 will be launched by United Launch Alliance, aboard a Delta IV evolved expendable launch vehicle.

The Delta IV Medium+ (5,4) configuration will use a single common booster core with a Pratt & Whitney Rocketdyne RS-68 main engine with four Alliant Techsystems GEM 60 solid rocket motors, for the launch.

The Delta IV will also be have a PWR RL10B-2 upper stage engine and a 5m diameter upper stage and composite payload fairing.

Part of a new high-capacity satellite communications system, the WGS-4 will provide enhanced communications capabilities to US troops during critical operations in future.

The WGS will also perform command and control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR), and battle management and combat support information functions in a robust and flexible manner.

The fourth satellite of the WGS system and the first in the block II series, the WGS-4 will be launched from Space Launch Complex-37 at Cape Canaveral Air Force Station, Florida.

Following the launch, the WGS-4 will join the existing WGS-1, 2 and 3 satellites and provide additional information broadcast capabilities.