Atlas 5 rocket deploys new GPS navigation satellite
BY SPACEFLIGHT NOW
Posted: August 2, 2014
CAPE CANAVERAL -- A rocket launch to serve the world blasted off Friday night from Florida carrying a new Global Positioning System satellite to transmit omnipresent navigation and timing information to users across the planet.
Lifting off at 11:23 p.m. EDT, an Atlas 5 rocket set sail on a three-and-a-half-hour trek to reach the navigation network and deploy the GPS 2F-7 spacecraft into an orbit 11,000 nautical miles high and tilted 55 degrees to the equator.
It was the second launch just this week for United Launch Alliance, which successfully flew its Delta 4 rocket on Monday night. In fact, it was the sixth national security space launch in less than four months for Atlas and Delta rockets, conducted in three pairs of flights in an unprecedented tempo in the life of the Evolved Expendable Launch Vehicle program.
Majestically clearing the towers at Complex 41, the Atlas-Centaur rocket began pitch, yaw and roll maneuvers to obtain the proper northeastward heading while minimizing aerodynamic stresses on the 189-foot-long rocket.
Atlas pushed through Mach 1 in 78 seconds and the region of maximum air pressure at 91 seconds, as planned, as the RD-180 main engine consumed kerosene fuel and supercold liquid oxygen.
Approaching booster engine cutoff four minutes into flight, the vehicle was burning propellants at a rate of 1,600 pounds per second, weighing only a quarter of what it did at liftoff before the first stage separated and the Centaur lit.
It was a lengthy first firing of Centaur that paralleled the eastern seaboard and flew above the North Atlantic, putting the vehicle into a preliminary orbit of 11,000 by 90 nautical miles.
"Positioning, Navigation and Timing provided by the Global Positioning System is widely recognized by military, civil, and commercial users, and is highly integrated into the Joint Force," said Lt. Gen. Jay Raymond, of U.S. Strategic Command's joint functional component command for space.
"The dependence of joint warfighting on GPS services and the asymmetric advantage they provide to our way of warfare means that we must protect and defend this vital capability or face the reality of conducting our operations under very different circumstances."
Valued at $245 million, GPS 2F-7 will take Plane F, Slot 3 of the constellation in a reshuffling plan that ultimately enhances the network.
The satellite currently in that spot -- GPS 2R-2, launched aboard Delta 245 in July 1997 -- will be freed to maneuver elsewhere within the same F Plane and replace the 22-year-old GPS 2A-14, one of the longest serving GPS spacecraft. It went up in July 1992 aboard Delta 211.
It was the third GPS launch since February, with one more planned for this year -- on Oct. 29 -- aboard another Atlas 5 rocket from the Cape to further bolster the constellation.
Two more Block 2Fs are due to launch next year -- in the spring aboard a Delta 4 and in June aboard an Atlas 5. The last two in the series flies in 2016 aboard Atlas 5 rockets.
The current constellation is comprised of six GPS 2A satellites, a dozen GPS 2Rs, seven 2R-Ms and six GPS 2Fs. GPS 2F-7 should be operational in four to six weeks.
"GPS is the Department of Defense's largest satellite constellation with 31 operational satellites on-orbit," Col. Bill Cooley, director of the Global Positioning System Directorate.
The next Atlas 5 launch is scheduled for Aug. 13 from Vandenberg Air Force Base in California carrying the WorldView 3 commercial Earth-imaging spacecraft. The next Atlas launch from Cape Canaveral is planned for Sept. 16 with the mysterious CLIO satellite payload.
After the GPS 2F-8 deploy on Oct. 29, Atlas wraps up its year on Dec. 11 with a National Reconnaissance Office payload launch from Vandenberg Air Force Base in California.
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