Posted: Sat, Apr 19, 2003, 9:54 PM ET (0154 GMT)
NASA announced late Friday that it has delayed the launch of the Space Infrared Telescope Facility (SIRTF) spacecraft until mid-August because of continuing issues with its launch vehicle. SIRTF was scheduled to launch this month on the first flight of the Delta 2 Heavy, but engineers found problems with one of the nine strap-on boosters that require the motor to be replaced. According to a NASA statement, engineers identified "multiple delaminations within the layers of material that comprise the engine nozzle exit-cone liner" in the GEM 46 motor. The GEM 46 had originally been developed for the Delta 3 and was being used for the first time on the Delta 2, which normally uses smaller GEM 40 motors. NASA had previously delayed the launch of SIRTF from April 18 until the 26th to permit more time for inspections and analysis. The motor cannot be replaced in time to permit a launch before NASA has to focus on the launches of twin Mars Exploration Rovers scheduled for early and late June, hence the postponement until mid-August. The extended delay will allow NASA to launch the Galaxy Evolution Explorer (GALEX) on a Pegasus booster on April 28; the launch has been scheduled for roughly a week after the SIRTF launch.
