Mission Control Center
STS-66 Status Report #16

Friday,  November 11,  5 p.m. CST

The STS-66 astronauts continued their observations of Earth’s atmosphere
and the other experiments on board Atlantis with only a few problems
punctuating their ninth day in orbit. 

The ATLAS-3 observations were put on hold for a little more than an hour
today due to an electrical problem. A power inverter that converts direct
current electricity to alternating current electricity for the ATLAS
instruments and their support equipment shut down unexpectedly. Payload
Commander Ellen Ochoa aboard Atlantis quickly switched to a backup
inverter that repowered the equipment. However, to ensure there was not an
electrical problem with the instruments themselves, flight controllers
delayed observations for a short while to analyze the situation. 
Observations with the ATLAS-3 instruments resumed about 4 p.m. 

Also, the crew switched the onboard flight control computer being used for
systems management to a backup mass memory unit after a connection between
the computer and the primary MMU proved faulty. Both the computer, one of
five flight control computers on board Atlantis, and the MMU are in
excellent condition. The problem was only in the connection between the
two devices. To restore full backup capability onboard, flight controllers
may eventually ask the crew to switch the Systems Manager function to a
different computer and assign another function to the current SM computer. 

During the day, Mission Specialist Joe Tanner took a brief break to talk
with a Chicago radio station, answering questions about Atlantis’s. 
Commander Don McMonagle took a phone call from Dr. Herman Smith, a retired
Marine Corps Captain in Houstan’s VA Medical Center, to commemorate
Veterans Day and christen a new patient bedside telephone system. 

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