The US Air Force (USAF) has taken delivery of the fourth Wideband Global SATCOM (WGS) military communications satellite from Boeing, following completion of on-orbit testing in January 2012.

Boeing Space & Intelligence Systems vice president and general manager Craig Cooning said the fourth WGS satellite adds substantial capacity and resiliency to the WGS constellation.

During the on-orbit testing at Cape Canaveral Air Force Station in Florida, US, the satellite was launched aboard a United Launch Alliance Delta IV rocket to demonstrate its communications payload features functionality by passing test signals through each of its 19 antenna beams.

The tests also validated the satellite’s beam-steering functions.

WGS-4, the first spacecraft in the programme’s upgraded Block II series, features a switchable radio frequency bypass to enable faster relay of airborne intelligence, surveillance and reconnaissance imagery at data rates three times greater than Block I satellites.

The satellite is expected to join the existing WGS-1, 2 and 3 satellites in mid 2012, to help provide additional communications capability to the USAF.

Schriever Air Force Base operations personnel are currently conducting additional tests and preparing to move WGS-4 into its operational position.

Built on the Boeing 702HP platform, WGS satellites feature efficient xenon-ion propulsion, deployable thermal radiators and advanced triple-junction gallium-arsenide solar arrays that enable high-capacity, flexible payloads.

The unique flexibility of the WGS communications payload allows it to interconnect terminals operating in different frequency bands and reposition coverage beams as per mission requirements.

USAF’s WGS constellation are designed to support missions including to and fro tactical communications between ground forces, and relaying data and imagery from airborne intelligence, surveillance and reconnaissance platforms.

Boeing has also been awarded a $673m contract modification by the air force for production and launch of the eighth and ninth WGS satellites in January 2012.