Saturday, July 2, 2011


ATLAS V (WGS-2), AV-016, 4 April 2009
On 4 April 2009 (8:31 p.m. on 3 April 2009 in local time), an ATLAS V 421 launch
vehicle equipped with a four-meter-diameter payload fairing, two SRBs, and a single-engine
CENTAUR upper stage lifted off Complex 41 successfully. The mission was designed to place
the second Wideband Global SATCOM spacecraft (WGS-2) in a geosynchronous transfer orbit.
Boeing Satellite Systems was under contract to build a total of six WGS spacecraft based on the
Boeing 702 satellite platform.
The new satellites were built and orbited to offset the eventual
decline of America‘s Defense Satellite Communications System III (DSCS III) constellation.
They also complemented DSCS III Service Life Enhancement Program (SLEP) spacecraft. Each
of the newer WGS-2 satellites supplied more than 10 times the capacity of instantaneous
bandwidth (e.g., 4.875 gigahertz) than the older DSCS III SLEP spacecraft. According to the
flight scenario, the ATLAS V rolled into a flight azimuth of 93.17 degrees. The flight featured
two CENTAUR burn phases, and the spacecraft separated successfully approximately half an
hour after lift-off. The  WGS-2 weighed approximately 13,000 pounds at lift-off, but a
considerable amount of onboard fuel was expended getting the satellite into its 22,300-mile-high
geosynchronous orbit. Consequently, the spacecraft‘s  mass  dropped to just 7,600 pounds onorbit.   Following a transition period, the  constellation of  six, new, fully-operational WGS
spacecraft would replace the old DSCS III constellation around 2013.
On 9 April 2008, Eastern Range officials approved the WGS-2 launch for 6 August
2008, but the mission moved into indefinite status shortly thereafter. A new launch date of 11
October 2008 was requested on 27 May 2008, and officials approved it in early June 2008. The
mission continued to see-saw back and forth between indefinite status and new launch dates over
the next nine months as planners continued to wrestle with technical issues. In the meantime,
however, technicians and engineers managed to erect the ATLAS V booster on its stand on 27
June 2008. The two SRBs were attached to the ATLAS V on 2 July 2008, and engineers erected
the CENTAUR upper stage one week later. Officials completed a Launch Vehicle Readiness
Test on 14 July, and they wrapped up a Wet Dress Rehearsal on 8 October 2008. The spacecraft
45 SW History, 1 Jan  – 31  Dec 2007, Vol I, p 88; News Release, ULA, ―United Launch Alliance Atlas V
Successfully Launches NRO Satellite,‖ 10 Dec 2007.
The first WGS-2 satellite was designated WGS-2 (F-1), and it was launched aboard an ATLAS V from Complex
41 on 11 October 2007. Each satellite cost approximately $350 million. Those satellites launched on ATLAS V
vehicles were designated WGS-2 spacecraft. Other WGS satellites  – earmarked for DELTA IV missions  – were
designated WGS-3 spacecraft.
45 SW History, 1 Jan – 31 Dec 2009, Vol I, pp 95, 96; Justin Ray, ―Atlas 5 rocket successfully launches military
satellite,‖, 3 Apr 2009; 45 SW Public Affairs, ―New satellite will grow warfighter capabilities,‖
45th Space Wing Missileer, 10 Apr 2009; News Release, Boeing, ―Boeing-Built Satellite WGS-2 Sends 1st Signals
From Space,‖ 6 Apr 09; Fact Sheet, ―Wideband Global SATCOM Satellite,‖, Feb 2010.37
was encapsulated on 25 February 2009, and engineers mated the spacecraft to the launch vehicle
on 4 March 2009. Officials completed the Spacecraft/Launch Vehicle Integrated Test on 6 March
2009. They anticipated a tentative launch date  of 17 March 2009, assuming the Space Shuttle
Discovery’s STS-119 countdown went on 15 March 2009.
Following Discovery’s successful lift-off from Complex 39A, preparations for the WGS-
2 flight got underway on 17 March 2009. Unfortunately, a valve on the CENTAUR upper stage
sprang a leak during fueling operations, and the ATLAS V launch was scrubbed at 2349Z on 18
March 2009. Officials approved a new launch date of 1 April 2009, pending determination of the
root cause for the valve malfunction and proper corrective action. The countdown slipped to 3
April 2009 a few days later. There were no unplanned holds during the countdown, and the
ATLAS V lifted off without incident at 0031:00.233Z on 4 April 2009. The mission was