STS-35

Infobox Space mission
mission_name = STS-35
insignia = Sts-35-patch.svg
shuttle = Columbia
launch_pad = 39-B
launch = December 2, 1990, 1:49:01 a.m. EST
landing = December 10, 1990, 9:54:08 p.m. PST, Runway 22, Edwards Air Force Base, Calif.
duration = 8/23:05:08
altitude = 190 nautical miles (352 km)
inclination = 28.45 degrees
orbits = 144
distance = 3,728,636 miles (6,000,658 km)
crew_photo = Sts-35-crew.gif
crew_caption =
previous = STS-38
next = STS-37

STS-35 was the tenth flight of Space Shuttle "Columbia", the thirty-eighth shuttle flight, and a mission devoted to deploying ASTRO-1, an observatory consisting of 4 telescopes. The mission launched from Kennedy Space Center in Florida on December 2, 1990.

Crew

Number in parentheses indicates number of spaceflights by each individual prior to and including this mission.

* Vance D. Brand (4), Commander
* Guy S. Gardner (2), Pilot
* Jeffrey A. Hoffman (2), Mission Specialist 1
* John M. Lounge (3), Mission Specialist 2
* Robert A. Parker (2), Mission Specialist 3
* Samuel T. Durrance (1), Payload Specialist 1
* Ronald A. Parise (1), Payload Specialist 2

Crew Notes

Jon McBride was originally assigned to command this mission, which would have been his second spaceflight. He chose to retire from NASA in May 1989 and was replaced as mission commander by Vance Brand.

Mission parameters

*Mass:
**"Orbiter Liftoff:" 121,344 kg
**"Orbiter Landing:" 102,462 kg
**"Payload:" 12,095 kg
*Perigee: 352 km
*Apogee: 362 km
*Inclination: 28.5°
*Period: 91.7 min

Mission highlights

December 2, 1990, 1:49:01 a.m. EST. Launch first scheduled for May 16, 1990. Following Flight Readiness Review (FRR), announcement of firm launch date delayed to change out a faulty freon coolant loop proportional valve in orbiter's coolant system. At subsequent Delta FRR, date set for May 30. Launch on May 30 scrubbed during tanking due to minor hydrogen leak in tail service mast on mobile launcher platform and major leak in external tank/orbiter 17 inch (432 mm) quick disconnect assembly. Hydrogen also detected in orbiter's aft compartment believed associated with leak involving 17 inch (432 mm) umbilical assembly.

Leakage at 17 inch (432 mm) umbilical confirmed by mini-tanking test June 6. Could not repair at pad and orbiter returned to VAB June 12, demated and transferred to OPF. Changeout of orbiter-side 17 inch (432 mm) umbilical assembly made with one borrowed from Shuttle "Endeavour"; external tank fitted with new umbilical hardware. ASTRO-1 payload reserviced regularly and remained in "Columbia"’s cargo bay during orbiter repairs and reprocessing.

"Columbia" rolled out to Pad A for second time August 9 to support a September 1 launch date. Two days before launch, avionics box on BBXRT portion of ASTRO-1 payload malfunctioned and had to be changed out and retested. Launch rescheduled for September 6. During tanking, high concentrations of hydrogen detected in orbiter's aft compartment, forcing another postponement. NASA managers concluded that "Columbia" had experienced separate hydrogen leaks from beginning: one of umbilical assembly (now replaced) and one or more in aft compartment which had resurfaced. Suspicion focused on package of three hydrogen recirculation pumps in aft compartment. These were replaced and retested. Damaged Teflon cover seal in main engine number three hydrogen prevalve replaced. Launch rescheduled for September 18. Fuel leak in aft compartment resurfaced during tanking and mission scrubbed again. STS-35 mission put on hold until problem resolved by special tiger team assigned by Space Shuttle director.

"Columbia" transferred to Pad B October 8 to make room for "Atlantis" on Mission STS-38. Tropical storm Klaus forced rollback to VAB October 9. Vehicle transferred to Pad B again October 14. Mini-tanking test conducted October 30, using special sensors and video cameras and employing a see-through Plexiglas aft compartment door. No excessive hydrogen leakage detected. Liftoff December 2 delayed 21 minutes to allow Air Force range time to observe low-level clouds that might impede tracking of Shuttle ascent. Launch Weight: 256,385 lb (116,294 kg). As of today, this is the most delayed launch of the space shuttle program.

Primary objectives were round-the-clock observations of celestial sphere in ultraviolet and X-ray astronomy with ASTRO-1 observatory consisting of four telescopes: Hopkins Ultraviolet Telescope (HUT); Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); Ultraviolet Imaging Telescope (UIT); and Broad Band X-Ray Telescope (BBXRT). Ultraviolet telescopes mounted on Spacelab elements in cargo bay were to be operated in shifts by flight crew. Loss of both data display units (used for pointing telescopes and operating experiments) during mission impacted crew-aiming procedures and forced ground teams at Marshall Space Flight Center to aim ultraviolet telescopes with fine-tuning by flight crew. BBXRT, also mounted in cargo bay, was directed from outset by ground-based operators at Goddard Space Flight Center and not affected. Other experiments: Shuttle Amateur Radio Experiment-2 (SAREX-2); ground-based experiment to calibrate electro-optical sensors at Air Force Maui Optical Site (AMOS) in Hawaii; and crew conducted Space Classroom Program: Assignment: The Stars, to spark student interest in science, math and technology. Crew experienced trouble dumping waste water due to clogged drain, but managed using spare containers. Mission cut short one day due to impending bad weather at primary landing site, Edwards Air Force Base, California. Science teams at Marshall and Goddard Space Flight Centers estimated 70 percent of planned science data achieved.

December 10, 1990, 9:54:08 p.m. PST, Runway 22, Edwards Air Force Base, CA. Rollout Distance: 10,447 feet (3.184 km). Rollout Time: 58 seconds. "Columbia" returned to KSC on December 20. Landing Weight: 225,329 lb (102,208 kg).

ee also

*Space science
*Space shuttle
*List of space shuttle missions
*List of human spaceflights chronologically

External links

* [http://science.ksc.nasa.gov/shuttle/missions/sts-35/mission-sts-35.html NASA mission summary]
* [http://www.nss.org/resources/library/shuttlevideos/shuttle38.htm STS-35 Video Highlights]