SHUTTLE'S JOURNEY TO PALMDALE DELAYED.

Byline: Jim Skeen Daily News Staff Writer

Space shuttle Columbia's arrival in Palmdale for modifications is being pushed back three months, to late August, as a result of changes in NASA's launch schedule.

Columbia's delayed return to Palmdale is the result of slips in the preparation of the orbiter's next payload, the X-ray telescope Chandra. The Chandra flight, originally planned for January, has slipped to July.

``We're not anticipating any large layoffs,'' said Alan Buis, spokesman for Boeing's Reusable Space Systems Division. ``The worst case is a couple of dozen would be temporarily laid off, but that might not happen.''

Columbia is tentatively scheduled to arrive Aug. 29 at U.S. Air Force Plant 42 for modifications by the Boeing division, which is is in negotiations with United Space Alliance, NASA's prime shuttle contractor, for the modification contract.

When Columbia does arrive in Palmdale, it will receive modifications similar to those Boeing performed on the orbiter Atlantis last year - an effort Boeing officials described as the most extensive modification effort yet. The Atlantis modification work cost $70 million and lasted 10 months.

During Atlantis' stay, workers installed a glass cockpit, touch-screen electronic display panels that replaced its 1970s video screens and mechanical gauges.

Workers also put in a modern global positioning navigation system, which tells the shuttle where it is in space using signals from orbiting satellites that the shuttle fleet helped launch.

Previous shuttle modification efforts have employed about 300 people.

National Aeronautics and Space Administration studies indicate performing the modifications in Palmdale costs about $5.3 million more than doing the work in Florida. However, the Kennedy Space Center cannot launch nine to 12 flights a year and at the same time perform modifications without building $48.8 million in additional facilities.