yee@trident.arc.nasa.gov (Peter E. Yee) (09/19/90)
KSC SHUTTLE STATUS REPORT - TUESDAY, SEPT. 18, 1990 11:30 AM STS-35 - COLUMBIA (OV 102) - PAD 39-A Launch of Columbia was scrubbed last night at about 6:35 p.m. EDT when concentrations of hydrogen in the aft compartment began climbing. The scrub was called shortly after the tanking operation of liquid hydrogen transitioned from the "slow-fill" to the "fast-fill" mode. The team continued troubleshooting the source of the leak for the remainder of the evening. Engineers are analyzing the data collected. The source of the leak has not yet been iden- tified. Officials are discussing the troubleshooting test results and will determine a course of action for further testing. There is a possibility of conducting another tanking test. The details and date of the test are being discussed. Today, the residual hydrogen in the external tank is being boiled off and is expected to be complete late tonight. A purge of the tank will follow the boiloff. After the tank has been purged, the power reactant storage and distribution system storage tanks will be drained of the liq- uid hydrogen and liquid oxygen reactants. Access to the aft compartment is expected late tomorrow af- ternoon. The aft compartment flight doors are scheduled to be removed tomorrow morning and platforms will be installed for ac- cess in the aft. The Rotating Service Structure was moved back around the vehicle at about 9:15 a.m. this morning. The Orbiter Midbody Um- bilical Unit is currently being connected to the vehicle in preparation for offloading the onboard reactants. The payload bay doors are scheduled to be opened tomorrow. The STS-35 flight crew departed KSC at 11 a.m. today, bound for Houston to continue mission training at the Johnson Space Center. STS-41 - DISCOVERY (OV 103) - PAD 39-B Hypergolic propellants were loaded aboard the orbiter this past weekend. Work to replace a fuel duct on main engine 2 is continuing today. This activity is scheduled to be complete later this week. A flight readiness test of the main engines is planned Thursday and a partial helium signature test is set for late Friday to check the new duct. Flight batteries for the Ulysses Inertial Upper Stage are scheduled to be installed Thursday. STS-38 - ATLANTIS (OV 104) - OPF BAY 2 Servicing activities of the freon coolant loop are continu- ing this week. An auxiliary power unit controller was reinstalled. Atlantis is being prepared for rollover to the VAB the end of the month.