United Launch Alliance Sends Communications Satellites to Orbit
The evening of March 15th brought the second United Launch Alliance (ULA) launch of 2019, the first of the year from the Launch Complex 37 site at Cape Canaveral Air Force Station in Florida. ULA supported the launch of the tenth Wideband Global SATCOM (WGS-10) communications satellite for the United States Air Force using their Delta IV rocket.

According to the ULA Launch profile, the WGS-10 launch utilized the Medium+ (5,4) configuration of the ULA Delta IV rocket. The single common core Delta IV M+ relies on a RS-68A engine system assisted by 4 solid rocket motors to provide additional thrust. It stands approximately 218 ft tall including a 47 ft payload fairing (PLF) that encapsulates the payload during flight. It is also comprised of the Delta Cryogenic Second Stage (DCSS) that supports the spacecraft into orbit once first stage separation occurs.
WGS-10 is the fourth Block II follow-on spacecraft to be deployed into the constellation of communications satellites utilized by the United States Department of Defense. This satellite is capable of delivering communications using the X-band and Ka-band spectra.


This launch closes out a series of ten launches of the WGS constellation, eight supported by the Delta Iv M+ configuration, two supported by the Atlas V configuration.

The March 15th launch was initially scheduled for 6:56 p.m. however, there were anomalies that arose during countdown that required all ground teams to work together and delayed the flight well into the 2 hour launch window. First, the teams on the pad did not clear in time to begin fueling procedures which resulted in a new targeted lift off time of 7:11 p.m. This launch time held until an issue with the pressurization of a first stage helium bottle arose and pushed the lift off to 7:52 p.m. Finally an issue with NASA’s Tracking and Data Relay Satellite System (TDRSS), which provides ascent telemetry data tracking information during launch, pushed lift off even further into the window for a final targeted launch time of 8:26 p.m.

Once launch occurred, all flight teams reported nominal launch, flight, and satellite deployment operations. This was the 39th successful launch of the Delta IV since its debut in 2002.



The final flight of the Delta IV M+ (4,2) is expected in July of this year carrying a Lockheed Martin Global Positioning System (GPS) navigation satellite to orbit for the United States Air Force.
Please visit our WGS-10 launch gallery under the Gallery tab for all launch photography.
To view launch & deployment in its entirety please view the launch stream below.