Atlantis Commander Chris Ferguson has begun troubleshooting General Purpose Computer (GPC) 4, one of the four primary shuttle GPCs. GPC 4 was being used as the systems management computer when it failed at 6:07 p.m. EDT Thursday, generating an alarm that awakened the Atlantis crew. Ferguson configured GPC 2 as the systems management computer before going back to sleep 45 minutes later. A fifth GPC is loaded with backup software and operates independently, ready to take over in case of an endemic problem with the four primary computers.
While troubleshooting is underway on GPC 4, GPCs 1 & 2 are operating Atlantis’ systems and GPC 3 is in a standby mode. The first step in today’s procedure is underway, transmitting the memory of GPC 4 to Mission Control for evaluation.