Apr 15 1985
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(New page: The turnaround clock began running when the Space Shuttle Discovery left the KSC launch pad at 8:59 a.m. April 12 and stopped 70 hours and 35 minutes later...)
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The turnaround clock began running when the Space Shuttle Discovery left the KSC launch pad at 8:59 a.m. April 12 and stopped 70 hours and 35 minutes later when NASA declared the orbiter Challenger, configured for launch of the Spacelab 3 mission, "hard down" on the pad, the KSC Spaceport News reported.
The tightly coordinated effort began approximately one minute after Discovery's launch. After launch control center's firing room 1 issued the command for automatic washdown of the pad structures, an operational TV scan, ordnance system resistance checks, and statusing fire and leak detectors commenced operation. About 15 minutes after launch, when it was certain the Space Shuttle would not return to the launch site, a convoy of waiting vehicles moved into action.
Workers dumped small cryogenic (hydrogen and oxygen) tanks at the 155-foot level of the fixed service structures (FSS). Two Lockheed and EG&G teams inspected in minutes the hydrogen and oxygen farms, high-pressure hydrogen gas battery, and the gaseous battery beneath the pad, clearing the way for another team to safe and secure the oxygen and hydrogen farms. Following dumping of the cryogenic tanks, two other teams began a level-by level quick-look inspection of the FSS and rotating service structure, setting the stage for safety and security procedures, including configuring purge line valves and doors, making environmental checks in the mobile launch platform (MLP), and checking operation of elevators. At the same time, others removed ordnance from the external tank vent arm and tail service masts, secured guard rails where necessary, and cleared the pad for entry of general repair crews.
Some damage was anticipated during a launch. In this case, pins had melted off some of the solid-fuel rocket booster holddown posts on the MLP; burnaway (or sacrificial) plates needed repairing; FSS light bulbs had blown at various levels; and some SRB waste residue was present. A 40-foot piece of waterpipe at the 95-foot level of the FSS, part of the Firex system, was bent at a 90° angle.
The KSC integrated control schedule called for removal of the MLP by 7 p.m. the day after launch and for it to be at the doors of the Vehicle Assembly Building (VAB) by midnight. To accomplish this, workers had to mount service platforms, disconnect waterpipes, and move flame deflectors. They also serviced the hydrogen burn pond and its several igniters.
On schedule, the crawler/transporter crew moved into position to begin the return of the MLP to the VAB. At 11:30 p.m. April 13, crawler 1 and MLP 1 reached the entrance of high bay 3; at 12:17 the next day the crew started the journey to the pad with Challenger. The Space Shuttle was "hard down" on the pad at 6:25 a.m. April 15. (KSC Spaceport News, Apr 26/85, 4)
NASA announced that Edward Taylor, a technician at Langley Research Center, modified an existing system, the uresco ultrasonic immersion testing system, by adding a holding device that permits accurate ultrasonic testing of small diameter polymeric tubes used in research programs, particularly small graphite fiber reinforced epoxy specimens, testing which formerly had to be done by hand.
The existing uresco system could not test curved or cylindrical shapes. Taylor's device rotated the tubes about their longitudinal axis while a high-frequency sound wave, transmitted through the tube wall, checked for flaws. This new method would permit nondestructive testing of tubular specimens without altering the electronic or mechanical configuration of the system.
Engineers checked graphite tubes for defects, trapped gases, void spaces, or foreign elements like a piece of metal. If they found a defect, engineers then decided if the tube would perform as one homogeneous material; if not, it was discarded. (NASA Release 85-57)
NASA announced it selected McDonnell Douglas Astronautics Co. and Rockwell Internatl.'s Space Station Systems Division for fixed-price con- tracts for definition and preliminary design (Phase B) of the structural framework and other elements of a permanently manned Space Station. Johnson Space Center (JSC) would manage the 21-month contracts, which had an estimated value of $27 million each. NASA previously announced other industry teams selected for negotiations for definition and preliminary design of other Space Station elements [see March 14].
In addition to work on the Space Station structural framework, the JSC contracts would cover interface between the Space Station and Space Shuttle; mechanisms such as the remote manipulator systems; attitude and thermal control; communications and data management systems; plans for equipping a module with sleeping quarters, wardroom, and galley; and plans for extravehicular activity. (NASA Release 85-56)
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