Running two days late because of inclement weather, a Delta IV rocket with the Air Force’s Wideband Global SATCOM-3 (WGS-3) satellite roared into space today from Cape Canaveral's Space Launch Complex-37 at 8:47 p.m. EST today and successfully deployed WGS-3 into geostationary transfer orbit 41 minutes later. The WGS-3 mission is the third installment of the Wideband Global SATCOM (WGS) system which is a new high-capacity satellite communications system providing enhanced communications capabilities to America’s troops in the field for the next decade and beyond.
READ: DELTA IV WGS-3 MISSION BOOK FREE VIDEOS: WATCH VIDEO: OUR VIDEO OF THE LAUNCH OF WGS-3 WATCH VIDEO: DELTA IV LIFTS OFF WITH WGS-3 WATCH VIDEO: A REMOTE CAMERA CAPTURES THE DELTA LAUNCH ALL-ACCESS SUBSCRIBERS: DOWNLOAD VIDEO: OUR VIDEO OF THE LAUNCH OF WGS-3 DOWNLOAD VIDEO: DELTA IV LIFTS OFF WITH WGS-3 DOWNLOAD VIDEO: A REMOTE CAMERA CAPTURES THE DELTA LAUNCH DOWNLOAD VIDEO: LAUNCH WEBCAST REPLAY - PART 1 DOWNLOAD VIDEO: LAUNCH WEBCAST REPLAY - PART 2 DOWNLOAD VIDEO: REPLAY OF SCRUBBED LAUNCH ATTEMPT WEBCAST WGS satellites are designed to provide high-capacity communications to U.S. military forces. They will augment and eventually replace the Defense Satellite Communication System that has been the Department of Defense's backbone for satellite communications over the last two decades. WGS enables more robust and flexible execution of Command and Control, Communications, Computers, Intelligence, Surveillance, and Reconnaissance (C4ISR), as well as battle management and combat support information functions. WGS-3 augments the existing service available through the UHF F/O, WGS-1, and WGS-2 satellites by providing additional information broadcast capabilities. The Wideband Global Satcom system represents a huge leap in capability for the Department of Defense. For example, the first spacecraft alone is providing more capacity than the entire Defense Satellite Communications System (DSCS) constellation currently on orbit that it is replacing. This equates to 10 times the capacity of each DSCS satellite. The WGS-3 spacecraft is an approximately 13,200-lb communications satellite. WGS supports communications links in the 500 MHz range of the X-band and 1 GHz range of the Ka-band spectra. WGS can filter and route up to 4.875 GHz of instantaneous bandwidth. Depending on the mix of ground terminals, data rates, and modulation schemes employed, a WGS satellite can support data transmission rates between 2.4 and 3.6 Gbps. WGS has 19 independent coverage areas that can be positioned throughout its field of view. This includes eight steerable/shapeable X-band beams formed by separate transmit/receive phased arrays; 10 Ka-band beams served by independently steerable diplexed antennas (three with selectable RF polarization); and transmit/receive X-band Earth-coverage beams. WGS can tailor coverage areas and connect X-band and Ka-band users anywhere within its field of view. WGS spacecraft also feature innovative a xenon-ion propulsion system (XIPS), which is 10 times more efficient than conventional bipropellant systems, highly efficient triple-junction gallium arsenide solar cells, and deployable radiators with flexible heat pipes. Four 25-cm XIPS thrusters remove orbit eccentricity during transfer orbit operations. The thrusters are also used to perform orbit maintenance and any required station-change maneuvers during the mission’s life. The WGS-3 mission was launched on the first Delta IV Medium+ to fly in the 227 foot tall "5,4" configuration with four SRMs and the single-engine DCSS. The payload will be encapsulated in a 5-meter diameter payload fairing. The SRMs are approximately 60 in. in diameter and 53 ft. long, and are constructed of a graphite-epoxy composite. Two of the SRMs have thrust vector control (TVC) capabilities. The motors burned for approximately 94 seconds and were jettisoned approximately 6 seconds later. The WGS-3 mission began at T-5.5 seconds when the Delta Common Booster Core's RS-68 engine ignited, powered by liquid hydrgoen and oxygen. After verifying the pweformance of the main engine, computers commanded ignition of the four solid rocket boosters ignited at T-0.02 seconds and the rocket lifted off at T-0. Launch was delayed until the end of the approximately 82 minute launch window today because of wind shear in the upper atmosphere which could have exceeded the rocket's ability to compensate. The previous launch attempt on December 3 was delayed by thick clouds and rain and then finally scrubbed when an avionics card failed in ground support equipment used to collect data from the rocket on the launch pad. The 48-hour delay allowed for time to correct the ground support issue and for the weather to clear. Visible through partly cloudy skies from Melbourne 40 miles to the south, the Delta turned night into day as it climbed higher and faster, the roar of the solid rocket boosters rumbling across Cape. Maximum dynamic pressure occurs approximately 50 seconds into flight and at T+94 seconds, the four solid rocket motors burned out and were jettisoned in pairs at T+100 and 102 seconds. Unlike most expendable launch vehicles that release the payload fairing after first stage burnour and separation, the Delta IV M+ 5,4 jettisoned its payload fairing at at approximately 206 seconds into flight, followed 40 seconds later by main engine cutoff (MECO) at 346 seconds. Six seconds after MECO, the first stage and Delta Cryogenic Second Stage (DCSS) separated and the second stage ignited approximately 13 seconds later. At approximately 20 minutes into the mission, second stage engine cutoff 1 (SECO-1) occured, completing the first of two upper stage burns to place DCSS and WGS-3 into a preliminary parking orbit. Eight minutes later, the DCSS stage reoriented for restart and its second burn which began 28 minutes after launch. The second engine firing lasted approximately 3 minutes before the upper stage shut down for the final time. The WGS-3 spacecraft separation took place about 41 minutes after launch to complete another successful Delta IV EELV mission for the Air Force. This was third WGS satellite United Launch Alliance flew for the Air Force. The previous two WGS satellites were launched on an Atlas V in October 2007 and April 2009. The WGS program is the first Air Force program to launch on both an Atlas V and Delta IV Expendable Launch Vehicle since ULA was formed to combine management, manufacturing and operation of Lockheed Martin's Atlas V and Boeing's Delta IV launch vehicles. Secretary of the Air Force Michael Donley, who had planned to witness the launch from the Morrell Operations Center at CCAFS prior to a 24-hour weather delay, said he and the entire nation depend on the 45th Space Wing and other space associated programs. "The WGS provides a giant leap in communications bandwidth and technology," said Secretary Donley. "The launch of this satellite is another example of the Air Force bringing important and vital capabilities to our nation's military around the world." This mission marked the third flight of a Delta IV rocket this year from CCAFS, a record for one year. It also was the second launch of a WGS this year from here. WGS-2 launched atop an Atlas V rocket here April 3. "I am extremely proud to be a part of a team of space professionals that launched the third Wideband Global SATCOM satellite to complete the first phase of the WGS constellation," said Brig. Gen. Edward L. Bolton Jr., 45th Space Wing commander. "I am also pleased this marked our 20th launch of the year." (The Spacearium / SpaceflightNews.net) 
(Photo Credit: Pat Corkery / united Launch Alliance)
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