Delta 4 Delivers 5th WGS Satellite to Orbit in 1st Flight Since October Anomaly

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WASHINGTON — The U.S. Air Force’s fifth Wideband Global Satcom (WGS) X- and Ka-band communications satellite was delivered safely to orbit May 24, marking a successful return to flight for United Launch Alliance’s Delta 4 rocket following an upper stage anomaly that had grounded the rocket since October.

The Boeing-built WGS-5 satellite, the second of the upgraded Block 2 WGS satellites, was dropped off in a supersynchronous transfer orbit approximately 41 minutes after its Delta 4 launcher lifted off from Cape Canaveral Air Force Station, Fla., at 8:27 p.m. EDT. Boeing expects to maneuver the $342 million satellite into a circular geosynchronous orbit this summer.

WGS-5 will be the first satellite in the constellation to cover North America, according to Luke Schaub, chief of the Wideband Satcom Division in the Military Satellite Communications Systems Directorate at Air Force Space and Missile Systems Center, Los Angeles. The first four WGS satellites are positioned to cover other areas of the world “between the eastern Atlantic and western Pacific” — an area that includes the Middle East — and WGS 5 will bring the constellation to near worldwide coverage, he said.

Speaking to reporters during a prelaunch media teleconference May 9, Schaub said the new satellite will support Western Hemisphere-based defense organizations including U.S. Northern Command, Southern Command, Strategic Command and the Missile Defense Agency.

The WGS-5 launch had been scheduled for January but was postponed after the Pratt & Whitney Rocketdyne RL-10 upper-stage engine on the Delta 4 carrying the Air Force’s GPS 2F-3 satellite to orbit last October underperformed due to a fuel leak in the interior of the RL-10’s thrust chamber. The rocket’s guidance system and flight computers compensated for the lower thrust, delivering the Boeing-built navigation satellite to its proper orbit with the help of reserve fuel, United Launch Alliance said at the time.

The WGS-6 satellite, meanwhile, has completed testing at Boeing’s El Segundo, Calif., facilities and has been shipped to Cape Canaveral in preparation for a launch now scheduled for August. Four more satellites, WGS-7, -8, -9 and -10, are in production at Boeing Space and Intelligence Systems’ El Segundo satellite factory.