‘Star Wars’ Shuttle Flight Prepared for Early Liftoff

With good weather expected, the shuttle Discovery and its seven-member crew were cleared Saturday for liftoff early today on a delayed “Star Wars” research mission now running two months behind schedule.

Four days after a faulty fuel pump sensor scuttled a launch try, engineers at launch pad 39A planned to pump a half-million gallons of supercool liquid oxygen and liquid hydrogen rocket fuel back into Discovery’s external tank late Saturday for a planned liftoff at 4:01 a.m. PDT today.

With no technical problems under study, National Aeronautics and Space Administration managers said they were optimistic about finally getting Discovery airborne, despite the threat of early morning fog.

“Everything is going smoothly and there’s nothing but good news at this point,” NASA test director Albert Sofge told reporters after agency managers cleared the shuttle for flight. Air Force meteorologists called for an 80% chance of early morning fog that would delay an on-time liftoff.

But the rising sun was expected to burn off any such fog, and forecasters predicted a 90% chance of getting Discovery into orbit by the end of the ship’s three-hour, 20-minute launch period.

Commander Michael Coats, 45, and his crew planned to strap in aboard the $2-billion orbiter before dawn to await liftoff on the 40th shuttle mission, the second of six flights planned for 1991.

A launch try Tuesday ended in failure six hours before liftoff because of abnormal readings from a main engine fuel pump pressure sensor. The faulty “transducer” was replaced by NASA workers and the shuttle was cleared for another launch attempt.

The astronauts planned to spend their first day in space activating the shuttle’s payload, a $260-million battery of military experiments, most of them which are devoted to Strategic Defense Initiative--”Star Wars”--missile defense research.

The goal of the mission is to learn how to detect small, hard-to-find enemy missiles against a variety of backgrounds so that future battle stations can launch interceptors or fire energy weapons in time to blast such rockets out of space.

While the results of the mission will be kept secret, details about the flight itself are not classified, the first time in shuttle history that a military mission has been openly conducted.

NASA originally hoped to launch Discovery on Feb. 26, but the flight was delayed more than a week because of work to replace three leaking rocket thrusters.

A March 9 launch date also passed by the wayside after engineers discovered cracks in the hinges of critical fuel line doors in the belly of the orbiter that must close properly in orbit to allow a safe re-entry.

Discovery is scheduled to land May 6 at Edwards Air Force Base in California.