GPS IIR-15 in Orbit

A ‘replenishment’ Block-IIR Global Positioning System (GPS) satellite for the U.S. Air Force has been put into orbit. The Delta II rocket carrying the GPS IIR-15 (M) spacecraft lifted off from Space Launch Complex 17A at Cape Canaveral Air Force Station, FL, USA, at 2.50pm EDT on 24th September. Following a nominal 68-minute flight, the rocket deployed the satellite into a transfer orbit. The GPS IIR-15 (M) is the second of the modernised GPS satellites incorporating various improvements to provide enhanced accuracy, resistance to interference and performance for users. The Boeing Delta II 7925-9.5 configuration vehicle used for the mission featured a Boeing first-stage booster powered by Pratt & Whitney Rocketdyne RS-27A main engine and nine Alliant Techsystems (ATK) solid rocket boosters. An Aerojet AJ10-118K engine powered the storable-propellant restart-able second stage. A Thiokol Star-48B solid rocket motor propelled the third stage leading to spacecraft deployment. The rocket flew with a nine-and-a-half-foot-diameter Boeing payload fairing.