yee@ames.arc.nasa.gov (Peter E. Yee) (07/29/88)
KSC SPACE SHUTTLE PROCESSING REPORT FOR - Thurs., July 28, 1988
STS-26 - DISCOVERY (OV 103) - PAD 39-B
The countdown for the Wet Countdown Demonstration Test is
scheduled to resume at 11 a.m. today at the T-11 hour mark. At
that time the Rotating Service Structure is scheduled to be moved
to the park position away from the vehicle.
The countdown clock will proceed to the T-8 hour mark and
will go into a built-in hold for a duration of three hours, 25
minutes. Operations scheduled while the clock is counting include
warming up the inertial measurement units, activating the fuel
cells and configuring the orbiter's communications systems for
the test.
Countdown activities will continue through the planned hold
at the T-8 hour mark at 2 p.m. to assure readiness for filling
the external tank with propellants tonight.
At 5:25 p.m., the countdown clock is scheduled to resume at
the T-8 hour mark. Preparations for loading the tank begin at the
T-6 hour mark at 7:25 p.m. The tank should be full of its half
million gallons of liquid oxygen and liquid hydrogen by 10:25
p.m. tonight.
At the T minus one hour, 10 minute mark the countdown will
enter another built-in hold for three hours, 45 minutes. During
this time several special tanking tests will be conducted using
both the liquid oxygen and liquid hydrogen systems. If the tests
are completed early, the countdown will proceed on toward the T-0
mark and if the tests run longer than planned, the count will
hold until the tests are completed.
Currently, the T-0 is planned for 5:30 a.m. Friday and 10
minutes later the external tank will be drained as scrub\turn
around activities are exercised. The clock will actually stop at
the T-10 second mark. The main engines will not be fired during
this test and the main engine start command is initiated inside
the T-10 second period.
The T-0 was moved up to give workers additional time to
perform post-test inspections of the solid rocket booster
hydraulic power units and to remove instrumentation from the
external tank inter tank area. These activities are art of the
turn around for the FRF.
The T-0 for the Flight Readiness Firing is planned for 7:30
a.m. Monday, August 1.