yee@trident.arc.nasa.gov (Peter E. Yee) (05/29/90)
Kennedy Space Center Shuttle status - Sunday, May 27, 1990 11 am
LAUNCH MINUS THREE DAYS
STS-35 - COLUMBIA (OV 102) - LAUNCH PAD 39-A
The STS-35 launch countdown began on time today at 1 a.m.
EDT at the T minus 43 hour mark. The countdown will lead up to a
planned liftoff of Columbia at 12:38 a.m. EDT on Wednesday, May
30. There are no problems with the vehicle or payload at this
time in the countdown.
Columbia's payload bay doors are scheduled to be closed for
flight this evening. The Astro-1 broad band x-ray telescope is
being serviced with argon today.
Today, technicians are removing platforms from the crew
cabin, removing engine covers and throat plugs from the orbital
maneuvering system and activating Columbia's navigation system.
The main engine controllers will be powered up for functional
checks and to checkout the gaseous nitrogen and helium purge sys-
tems.
At the pad, workers will be performing final cleaning and
wash down of the pad surface, flame trench and zero level of the
mobile launcher platform.
The countdown will enter the first of several built-in holds
at the T minus 27 hour mark at 5 p.m. this evening. After the
countdown clock resumes at 1 a.m. Monday, Columbia's fuel cell
storage tanks will be loaded with liquid oxygen and liquid
hydrogen reactants. For this countdown, Columbia's storage tanks
will be filled from tankers on the pad surface instead of from
the dewars at the Pad. This exercise will prove the capability to
load reactants from tankers, the method that will be used for an
extended duration orbiter flight. The capacity of the dewars at
the pad is not sufficient to support an EDO flight.
STS-35 flight crew members arrived at KSC's Shuttle Landing
Facility today at 11 a.m. for final flight preparations. Today,
the crew will be briefed on the status of the countdown and other
pertinent events.
Weather forecasts for the time of launch on Wednesday are
favorable with an 80 percent chance of being within required con-
ditions. Winds are forecast to be out of the southwest direction
at 12 knots. The expected temperature at the time of launch is 75
degrees. Clouds are forecast to be scattered at low mid and upper
levels.