STS-101 Mission Status Report #20

STS-101, Mission Control Center
Status Report # 20
Sunday, May 28, 2000 – 4 p.m. CDT

Atlantis’
astronauts were awakened at 3:11 p.m. CDT this afternoon to make final
preparations for their return to Earth following 10 days in space readying
the International Space Station for future occupation. Mission Control
awakened the astronauts to the march "El Capitan," by John
Philip Sousa.

Final deorbit
preparation begins at 8:13 p.m. CDT this evening on the crew’s timeline.
The space shuttle’s payload bay doors will be closed at 9:33 p.m. and
the spacecraft’s radiators will no longer provide cooling once they
are closed. Mission Control gives a "go" or "no go"
call for transition to the software phase known as "Ops 3"
at 9:45 p.m., shifting the onboard computers’ attention to deorbit and
entry tasks.

The astronauts
start getting into their launch/entry suits at 10:49 p.m., climb into
their seats at 11:13 p.m., perform a gimbal check of the Orbital Maneuvering
System engines at 11:35 p.m. and pre-start the auxiliary power units
to generate hydraulic power for the aerodynamic surfaces at 11:39 p.m.

The flight control
team in Mission Control will review the condition of the Shuttle Orbiter
and make a go/no go decision for the deorbit burn at 11:58 p.m. Atlantis
maneuvers to the deorbit burn attitude at midnight and fires the OMS
engines at 12:13 a.m. CDT to slow the forward speed and drop the spacecraft
from orbit. Touchdown is planned for 1:20 a.m. Central time Monday at
the Kennedy Space Center.

A second opportunity
for landing occurs one orbit later with a deorbit burn at 1:50 a.m.
and a landing at KSC at 2:56 a.m. CDT. The weather forecast for landing
indicates acceptable conditions, although forecasters will be monitoring
the progress of a front moving toward Florida throughout the day and
its potential effect on winds at the Shuttle Landing Facility runway.

Two opportunities
for a landing in Florida also are available on Tuesday and again on
Wednesday, if needed. Also on Wednesday, Atlantis could land at Edwards
Air Force Base, California, if required. Landing support will not be
called up for Edwards until Wednesday.

The next mission
status report will be issued following landing or wave-off Monday morning.

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