yee@trident.arc.nasa.gov (Peter E. Yee) (09/12/90)
This KSC status report was prepared at 11:30 a.m. Tuesday, Sept.11th. The countdown dress rehearsal for the STS-41 Discovery/Ulysses mission concluded at 11:07 with a planned simulated cutoff of Discovery's main engines. The astronauts are now scheduled to simulate an emergency egress from the orbiter. Today's successful countdown dress rehearsal is primarily an electrical test of the Space Shuttle systems and launch complex systems, and a procedural exercise for the astronauts working together with the launch team. In parallel, the payload test team conducted an exercise to simulate problems which could arise during the actual countdown. The test team's decisions on managing unexpected problems which could arise with Ulysses, the Inertial Upper Stage, or the Payload Assist Module will now be discussed. Data from the testing of Discovery's cooling system over the weekend shows that the small freon leak is not likely to worsen and that flying as is will be the KSC recommendation. The leak will continue to monitored, however, the leakage rate of about 1% per day is believed not likely to change. The next major step toward launch begins this afternoon with the Interface Verification Test between Ulysses with its attached upper stages and Discovery. This test verifies the electrical connections established between the payload and the orbiter, and also connections with the payload control panel and the associated computers on the flight deck. On Pad 39-A the work to install the liquid hydrogen recirculation pump package has been completed. Because the work took longer than scheduled to complete, the helium signature leak test of the hydrogen side of the main engines and main propulsion system was rescheduled from last night to second shift today. Launch is still targeted to occur toward the early part of next week. From the NASA Kennedy Space Center, this is George Diller.