COLUMBIA SCHEDULED TO DEPART KSC FOR MAJOR MODIFICATIONS IN PALMDALE, CA.

The orbiter Columbia, veteran of 26 Space Shuttle flights, is slated to depart Kennedy Space Center, FL, on Friday, Sept. 24, headed for Palmdale, CA. The oldest of four orbiters in NASA's fleet will undergo extensive inspections and modifications in Boeing's Orbiter Assembly Facility during a nine-month orbiter maintenance down period (OMDP).

This is Columbia's second OMDP, an action that periodically removes each of NASA's orbiters from flight operations. Though Columbia has undergone other major modifications in Palmdale, CA, its first OMDP was in 1994.

While in California, workers will perform more than 100 modifications on the vehicle. Columbia will be the second orbiter outfitted with the multi-functional electronic display system (MEDS) or "glass cockpit". Last year, 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 The new system improves crew interaction with the orbiter during flight and reduces the high cost of maintaining the outdated electromechanical cockpit displays currently onboard.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 her 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. Thus, Columbia will continue to be able to accommodate payloads requiring the orbiter's 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 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 as a result of the STS-93 mission.

Preparation work for an enhanced Global Positioning Satellite 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 communication capabilities for Columbia's future crew members and space walkers. In addition to scheduled weight saving modifications, Columbia's radiators or coolant lines will be enhanced for protection from orbital debris.

Columbia was rolled out of KSC's Orbiter Processing Facility bay 3 today, bound for the Shuttle Landing Facility's Mate-Demate Device. Later today, the orbiter will be mated, in "piggy-back" fashion, to the Boeing 747 Shuttle Carrier Aircraft (SCA). Ferry flight departure may occur as early as 7 a.m. Friday, Sept. 24.

The coupled orbiter and SCA are expected to make a one-day cross-country flight to California, with a planned refueling stop at the Naval Air Station in Fort Worth, Texas. All ferry flight plans are subject to weather restrictions and alternate landing sites may be selected en route if necessary. The original ferry flight plan included an overnight stop at Luke Air Force Base in Arizona for refueling and to accommodate several Air Force public affairs events. Following the crash of an F-16 at Luke on Monday and an expected one-day slip in Columbia's arrival in Arizona, Luke officials expressed Shuttle support concerns and agreed to cancel the visit.

Ferry flight rules state the orbiter/SCA cannot fly through precipitation, thick clouds or high turbulence. There are also wind and temperature restrictions. Following the modification period, Columbia is expected to return to KSC in July of 2000.

NOTE TO EDITORS: News media interested in viewing the orbiter/SCA departure from KSC must be at the KSC press site by 6 a.m. Friday for transport to the Shuttle Landing Facility. Media should call the KSC Press Site before close of business today to confirm the departure time.

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