ULA Delta IV Sends U.S. Air Force WGS Payload Thundering to Orbit

AmericaSpace's Mike Killian took this time-elapsed image from the Kennedy Space Center press site parking lot. Photo Credit: Mike Killian/ARES Institute

CAPE CANAVERAL, Fla – The U.S. Air Force launched the Wideband Global SATCOM-4 or WGS-4 satellite at 7:38 p.m. EST from Cape Canaveral Air Force Station’s Space Launch Complex-37 (SLC-37). 

The WGS-4 mission marks the 18th Delta IV launch and the second launch of the Delta IV Medium+ (5,4) launch vehicle in this configuration. As currently scheduled, ULA has 11 launches planned for this year.

“We are honored to have worked closely with our Air Force and mission partners to enable today’s successful launch of the WGS-4 satellite.  WGS-4 will provide important capabilities to the soldiers, sailors, airmen and marines protecting our freedoms around the world,” said Jim Sponnick, ULA vice president, Mission Operations. “This mission begins the most aggressive launch campaign in the history of the EELV program, with nine national security and two NASA launches scheduled this year.” 

The United Launch Alliance puts out an impressive display of fire and smoke as it lifts off from Space Launch Complex 37. Photo Credit: Pat Corkery/United Launch Alliance

This marks the fourth installment of the WGS system. These satellites are viewed as a crucial tool to provide enhanced communications capabilities to soldiers in the field. According to a ULA press release, the WGS system will allow for better execution of Command and Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance or C4lSR. 

WGS-4 is part of a partnership between the U.S. Department of Defense and the Australian Department of Defence.  

A Delta IV Medium turns night into day as seen from the NBC building located at the Kennedy Space Center press site. Photo Credit: Jason Rhian

Skies above Cape Canaveral remained clear throughout the day and into the evening giving providing favorable conditions for launch at 100 percent – a truly rare occurrence with the ever-changing weather conditions in Florida. 

This is only the second time that a Delta IV Medium has flown with four solid rocket boosters. The first time was for the launch of the WGS-3 satellite. Photo Credit: Jeffrey J. Soulliere

The Delta IV Medium-plus configuration, as it is known, uses a single common booster core powered by a Pratt & Whitney Rocketdyne RS-68 engine. Attached to the bottom of the first stage of this rocket are four Alliant Techsystems’ (ATK) GEM 60 solid rocket motors. The upper stage measures five meters in diameter and is powered by a PWR RL10B-2 engine with the satellite safely cocooned in a five-meter diameter composite payload fairing (also produced by ATK). The fairing made the rocket appear different as many Delta IV Medium’s fairings taper as they reach the top – this version did not, giving the rocket a more robust look. 

“It was a beautiful launch, said the 45th Space Wing’s Chief of Media Relations Christopher Calkins. “The 45th Space Wing is extremely proud of the partnership that propelled this crucial payload to orbit.”

United Launch Alliance successfully launched a Delta IV Medium with its WGS-4 payload from Cape Canaveral Air Force Station's Space Launch Complex-37. Photo Credit: Jason Rhian

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