NASA’s TDRS-4 Satellite Raised to Graveyard Orbit
A NASA Tracking and Data Relay Satellite (TDRS) launched in 1989 recently completed end-of-mission decommissioning activities that included boosting the retired satellite above the Earth’s congested geosynchronous orbital belt, NASA said May 8.
The satellite, dubbed TDRS-4, far exceeded its original 10-year design life and was ultimately forced into retirement by worn-out batteries. Built by TRW Space and Electronics Systems — which becamein 2002 — TDRS-4 is the second TDRS satellite to be retired. The first TDRS satellite taken out of service, TDRS-1, was decommissioned and raised to a graveyard orbit in June 2010.
NASA has seven TDRS satellites still in service and has Boeing Satellite Systems building three new TDRS craft under a fixed-price contract originally awarded in 2007 and now worth about $1.4 billion including an unexercised option for a fourth satellite. The first of those satellites, TDRS-K, is scheduled for launch in December followed by TDRS-L in 2013 and TDRS-M in 2015.
A U.S. Government Accountability Office report published in March — “NASA: Assessments of Large-Scale Projects” — blamed late subcontractor payload deliveries and technical issues found during spacecraft integration and testing for cost overruns and schedule erosion that ultimately prompted NASA to delay the launch of TDRS-K from June to December.
Launch is targeted for mid-December from Cape Canaveral Air Force Station, Fla., aboard aAtlas 5 rocket. TDRS-L would launch a year later, in December 2013.