Aerospace Technology Development

Maintenance, Mods and New Components for the Shuttle

NASA-Thiokol Agreement

NASA AND THIOKOL PROPULSION OF Brigham City, Utah, have completed negotiations for a contract for the postflight review, manufacture and delivery of 73 Space Shuttle Re-usable Solid Rocket Motors. "This purchase will support Shuttle launches for several more years," said Ben Goldberg, manager of the motor project at Marshall Space Flight Center. "This contract includes performance, as well as cost incentives for our industry partner. We're seeking ways to reduce cost while maintaining the important level of safety. Our overriding requirement in this program continues to be safety."

This glass cockpit initially installed in the orbiter Atlantis is currently being installed in Columbia. This upgrade improves crew-orbiter interaction with easy-to-read, graphic portrayals of key flight indicators such as attitude display and Mach speed.

In addition to 35 sets of flight motors, the contract also includes three motors that will be used in ground testing to ensure quality and prove new materials, manufacturing techniques and hardware suppliers. The manufacture and delivery of the new motor components to Kennedy Space Center in Florida is set to begin this fall and continue through September 2004.

The original solid fuel motor was redesigned in 1986. The motors—two used per flight—are the primary component of the Shuttle Solid Rocket Boosters. Providing 6.6 million pounds of thrust, or 71.4 percent of what the Shuttle needs for liftoff, they burn out after about 123 seconds and descend by parachute into the Atlantic Ocean.

Experts Study Shuttle Maintenance Practices

Following a recent discovery of maintenance-related damage to Space Shuttle electrical wiring, a team of leading aerospace experts, chaired by Ames Research Center Director Dr. Henry McDonald, has formed to review the overall safety of Shuttle maintenance and refurbishment practices and recommend improvements. Preliminary findings were expected sometime in the fall. The team also includes top maintenance experts from NASA, the military, the aerospace industry and the commercial aircraft industry and other experts from around the country.

Columbia Scheduled for Major Modifications

The orbiter Columbia, the oldest of the four Space Shuttles and veteran of 26 flights, is undergoing extensive inspections and modifications during a nine-month orbiter maintenance down period (OMDP) at Boeing's Orbiter Assembly Facility in Palmdale, California. This is Columbia's second OMDP, an action that periodically removes each of NASA's orbiters from flight operations. Its first OMDP was in 1994. It is expected to return to Kennedy Space Center in July 2000.

While in California, workers will perform more than 100 modifications on the vehicle. Columbia will be the second orbiter outfitted with the multifunctional electronic display system (MEDS), or "glass cockpit." Last year, the Shuttle Atlantis had the full-color, flat-panel displays installed on its flight deck during an OMDP. The new system improves crew interaction with the orbiter during flight and reduces the high cost of maintaining the outdated electromechanical cockpit displays currently onboard.

While sister ships are being outfitted with external airlocks in support of the International Space Station assembly, Columbia's internal airlock will not be removed during this OMDP to enable the orbiter to continue to accommodate payloads requiring its 60-foot-long cargo bay. Though not currently slated to dock with the International Space Station, Columbia will be given additional wire harnesses and connectors while at Palmdale to allow for the installation of the Orbiter Docking System at Kennedy Space Center. This prepares Columbia for docking operations with the space station if plans change.

While at Palmdale, Columbia's 100 miles of wiring will be given a thorough inspection. This is part of NASA's fleet-wide wiring inspection. The wiring problem was first identified on Columbia after the STS-93 mission.

Preparation work for an enhanced Global Positioning System capability will also be performed on Columbia. When installed, the new system will more accurately pinpoint the orbiter's location in flight.

A space-to-space orbiter radio and wireless video modification will increase communications capabilities for Columbia's future crewmembers and spacewalkers. In addition to scheduled weight- saving modifications, Columbia's radiators or coolant lines will be enhanced for protection from orbital debris.

For more information, visit http://spaceflight.nasa.gov/shuttle/index.html