A faint, eerie light illuminated the flight deck of the space shuttle simulator in Building 5 at the Johnson Space Center, where the five future crew members of the shuttle's seventh flight were practicing launching satellites.

Astronaut John Fabian sat in the commander's seat, in the left-front corner of the cockpit, checking data displayed on a computer screen against a checklist of procedures in a flight manual. Beside him, pilot Rick Hauck stared out the front window into the void.

Mission specialist Sally Ride, in faded jeans and a T-shirt, stood at the rear of the flight deck, flipping switches for Fabian. Astronaut Norman Thagard squatted in the center of the cabin, peering over Fabian's shoulder, and commander Bob Crippen, in sport shirt and slacks, gazed out the rear window.

Beyond that window, the open cargo bay glowed green against the ebony of space. Stars beamed in the blackness, lacking the twinkle normally provided by the atmosphere. Filling the left side of the window was the vertical curve of the Earth's surface. It was an odd-looking Earth, checkered in yellow and orange, without blue seas or white cloud spirals.

Crippen apologized for this minor failure of NASA's computers to live up to their legendary ability to create mock space flights that cannot be distinguished from the real thing. "It's better simulated out the front window," he said.

The crew was performing a four-hour simulation, one of the deadly serious, breathtakingly lifelike computer games used since the days of the Apollo program to train astronauts for every detail of their flights and to test their response to every combination of system failures that Space Center engineers can dream up.

This night's game was satellite deployment. The STS7 crew, scheduled to launch two satellites from the shuttle Challenger during their flight next month, were practicing launch procedures designed for the fifth shuttle flight last November. They are to use the same procedures on their own mission.

Through radio headsets they conferred with "L.D.," an invisible engineer masterminding the session from a control booth somewhere in the building.

Reading from his checklist, Fabian led Ride through a switch-flipping series to start the launch of ANIK, a Canadian communications satellite.

"We're coming up on 20 minutes," said Crippen, checking a digital clock on the flight-deck wall showing the countdown for the satellite launch.

"My recorder's on," Ride responded, after turning on the videotape recorder that would photograph the launch.

"The camera's ready," Fabian said. "We're entering the mechanical sequence in 18 seconds." That sequence, Crippen said, is an automatic process in which the sun shield protecting the satellite opens, restraints holding it are released and the satellite spins up into launch position in the cargo bay.

Outside, in the bay, the white dome of the sun shield split down the middle and folded apart like the two valves of a clamshell. In the shell's center, a pale, block-like object seemed to rise from the floor of the cargo bay. It began to spin slowly, then faster.

This was the ANIK satellite, mounted on the payload-assist module (PAM), the spring-like device that shoves the satellite upward, away from the shuttle. "It's starting to spin out. That's how it stabilizes," Crippen said.

Ride pulled out a cue card for the next procedure and read instructions to Fabian, who watched his display screen and talked back to the computer by punching buttons rapidly.

"Fuel cell!" he cried suddenly. A symbol on his screen indicated a failure in one of the shuttle's fuel cells.

"Let's ignore that. It ain't serious," Crippen said quickly.

Everybody laughed. "Isn't Crip wonderful to have around?" Ride said. Crippen helped design the shuttle, and his familiarity with its workings is a source of delight to the rest of his crew.

"That's me: Filter Crip," he said. "If you pay attention to every message you get around here, you never get to fly."

Four minutes later, ANIK took off, spinning and rising slowly out of the cargo bay, atop what looked like a glowing orange cylinder. It floated steadily upward, diminishing into the blackness.

Ride turned off the videotape recorders, Fabian closed the sun shield and they went to work again, this time preparing to deploy SBS, the business satellite launched on the fifth flight.

Time after time, they ran through the deployment procedures, encountering a computer failure here, a loss of communication there. Sometimes they salvaged the launch by switching to backup equipment. Other times they checked their flight rules and chose to abort.

In the world outside, beyond the vast, closely guarded hangar where the simulators are housed, the last game of baseball's World Series was in progress. "L.D." reported the score from time to time over the radio, but the shuttle crew, engrossed in its own game, hardly seemed to mind missing the play-by-play.

In the final months before the scheduled launch June 18 of STS7, Sally Ride's world has been a dizzying parade of simulator sessions, technical briefings and hours spent studying the stacks of procedure manuals that would govern every moment of her space flight. As one of the mission specialists, her duties aboard Challenger will include deploying satellites, manipulating the shuttle's mechanical arm, tending experiments being carried in the orbiter and repairing anything that breaks down in flight.

Her flight's launch was delayed about two months because of problems with a previous mission, but Ride said the postponements gave her extra training time. "It wasn't disappointing at all," she said. "I mean, shoot, who cares about two months?"

She was at her desk by 7 a.m. each day and often stayed in the simulator until 10 p.m. She ended the day sprawled on the rug in her den, clad in sweatshirt and jeans and perusing another manual while a "Burns and Allen" rerun on television provided background noise. She spent her lunch hours jogging or lifting weights in the Space Center gymnasium. When she felt the need for escape, she went flying with a fellow astronaut in a T38 jet.

"I have lost my dominant trait, which has been not to work at things," she said. "I'm really working hard, and I have been for three years. And I enjoy it. In fact, I'm obsessed with it."

Much of her time has been spent on the third floor of the Space Center's Building 4 in a large, cluttered office she has shared with the other crew members. In the last year, NASA has moved crews of upcoming shuttle flights into group offices, on the theory that the more time together during training, the better their teamwork in the orbiter.

As flight commander, Crippen has had his own office, decorated with awards and a lone pinup partially hidden behind a plant and opening off the bigger room inhabited by his crew, its walls papered with shuttle photos, orbit maps and posters. Ride's favorite poster showed the black silhouette of a turkey superimposed with a red circle and diagonal bar: a spoof using international code to say "No Turkeys Allowed."

Fabian and Hauck, both of whom entered the space program as astronauts with Ride in 1978, shared her elation over the approaching flight.

Fabian, 44, quit as professor of aeronautics at the Air Force Academy when he was chosen unexpectedly as a mission specialist.

"I had always been too tall or undereducated or not had enough flying time . . . when NASA was looking for crew members in the past," he said. "The chance to come to NASA seemed to be a very slim hope . . . but it really did seem to be a once-in-a-lifetime opportunity to get involved in something where you could contribute more than your time."

Hauck, 42, a former Navy test pilot with a master's degree in nuclear engineering, applied unsuccessfully to become an astronaut in 1964. Like Fabian, he had feared he was too old to be accepted in 1978. His sharp blue eyes became boyishly bright when he talked about the launch.

"I think the whole thing is going to be a tremendous experience," he said. "I think it's a totality . . . being almost free of the Earth's restrictions, being up there where you'll be able to see so much in such a short period of time . . . . "

Much of the time, the astronauts needed to draw on their excitement about flight in order to maintain interest in the mass of technical details that must be mastered during training. Almost daily, the crew met with engineers working on one or another of the shuttle's systems to learn procedures and ferret out flaws.

At a meeting one morning with three young programmers from the group working on the shuttle's mechanical arm, the astronauts discussed--in the impenetrable engineering slang spoken by everyone at the Space Center--their agenda for a training session.

"I think we'd like to do some track-and-capture positions," Fabian said. "Everybody always feels comfortable after they've done five or six track-and-captures and gotten their hands warmed up. We're hoping for any malfunctions you want to throw at us . . . . I'd like to see one or two MCIU-autosafing malfunctions and a couple of consistency check autobrakes . . . . It gets rather uninteresting after that."

What an uninitiated listener would not have realized is that the maneuvers Fabian was describing, when played out in space with the shuttle's mechanical arm, may create scenes worthy of the movie, "2001, A Space Odyssey." One of the objectives of the seventh flight is to perform an aerial ballet with an experimental German satellite called SPAS-01.

The astronauts are to place SPAS-01 in orbit, fire the shuttle's steering jets at it to watch how it wobbles, back 1,000 feet away, then approach it again and retrieve it with the arm. Meanwhile, cameras on SPAS-01 are to photograph the soaring of the shuttle and the arm's delicate maneuvers.

The purpose of the exercise is to demonstrate the arm's talent for retrieving objects from space. NASA hopes to use that talent to recapture and repair an ailing satellite during the shuttle's scheduled 13th flight in April, 1984.

Other training sessions dealt with more familiar skills, such as preparing food for meals on board. Crew members and their support crew spent several hours one morning in a life-sized mockup of the shuttle Columbia, learning how to operate the portable food heater and add ice water to packaged tea. At the end of the class, like high school home economics students, they were forced to eat the results for lunch.

"We had ham sandwiches, broccoli, crushed pineapple, cashews, cookies and peach ambrosia--which we all passed on," Ride said later as she stood in the mockup of the mid-deck.

The mockup, an exact facsimile of the shuttle's living quarters, is a metal room measuring perhaps 10 feet on each side, with a silver-colored floor gridded with storage hatches, and stark, white walls lined with rows of locker drawers. It is rather like being inside a bank vault.

Showing a visitor around, Ride opened her white plastic food tray with clear-topped compartments for ham, cheese spread, bread, mustard and other items. Two trays are stored together in a plastic bag inside a food locker. Crew members warm them in what looks like an aluminum suitcase containing electric heating coils. Proferring a leftover cookie, she said, "I'm still trying to convince the food people that I don't need 3,000 calories a day."

One by one, she opened the lockers, pulling out drawers full of cloth-bound procedure manuals, maps, reference tables, equipment diagrams, checklists. One fat book was labeled CAP for "crew activity plan." "This tells us what to do when--minute-by-minute stuff," she said.

Larger drawers contained cameras used by the astronauts to shoot television and movie footage of their life in space, a medical kit with bottles of antibiotics, motion-sickness pills and other drugs, and a complete tool kit.

"Rick Hauck and I are in charge of the tools," she said. "We're the two mechanics on the flight . . . . We can replace cathode ray tubes and change computers. I actually knew how to do that before, because I had to know how to do that for the capcom capsule communicator job."

Ride fingered a blue canvas hammock dangling from one wall of the living quarters.

"This is a sleeping bag," she said, "but it's not obvious that we need sleeping bags. We probably won't use them." Astronauts on past flights have often opted not to use the vertically suspended bags, preferring to sleep in seats in the cockpit or anchor themselves to floor or walls with tape or string so they will not float around the cabin.

In the middle of the cabin floor was the portable treadmill that can be anchored there when astronauts want to exercise. Straps called bungees fit over the shoulders to hold the astronaut in place and exert resistance to mimic gravity, so the exercise requires muscular effort.

"This is an access way up to the flight deck that you can float up," Ride said, pointing to a hole in the ceiling lined with white canvas. "We're supposed to keep our spacesuits here, but we're not going to. We'll keep 'em somewhere else. The most fun Crip had on his previous shuttle flight was floating to and from mid-deck, and he says we need to have that kind of fun, too."

A ladder led to the flight deck by a different route. Inside, large seats for the commander and pilot faced the small front windows, framed by a maze of instruments, keyboards, four computer display screens and panel upon panel of switches. Taped between the switches were typed cards with sequences of instructions in case of malfunctions.

Smaller seats swiveled out of the wall at the rear of the flight deck for the mission specialists, and large ceiling windows were designed to provide a view of the Earth, normally overhead when the shuttle is in orbit. Rear windows looked out over the mockup's cargo bay, the enormous deck where satellites and other experimental equipment are stored. During orbit, the roof of the cargo bay is open to the sky and Earth above.

Scrambling down the ladder to the mid-deck, Ride exclaimed, "And I forgot to show you this, the WCS."

The WCS, or waste collection system, is the toilet that makes it possible for the shuttle to accommodate astronauts of both sexes. Housed in a closet in one wall of the living quarters, it operates by air suction and looks much like an airplane lavatory. "Supposedly, it works pretty well," she said.

During Ride's training, every aspect of the mission was broken down into components and rehearsed, first in the classroom or in the shuttle mockup, which looks like the real thing but does not contain working computers. Later it was done in the simulator, in which all switches connect to computers programmed to create potential in-flight situations.

The astronauts' most elaborate and stressful training took place during "integrated sims," sessions in which all of Mission Control is staffed with engineers and programmers who work with the crew in the simulator as if they were in space.

During these sessions, which can last as long as 56 hours and may cover the events of an entire flight, programmers called "sim sups" simulation supervisors throw in failures affecting every shuttle system. That is to test not only the astronauts but also hundreds of engineers monitoring the flight on the ground.

Overseeing each system is an engineer at a console in the Space Center's Mission Control room, using radio communication and a computer terminal to track ever-changing data on such topics as the shuttle's altitude, speed and coordinates, its electrical and environmental equipment, the state of its engines and fuel supply, and weather conditions.

Each system's representative, known by acronyms such as "FIDO" or "EECOM, communicates over radio headsets antibiotics, motion-sickness pills and other drugs, and a complete tool kit.

"Rick Hauck and I are in charge of the tools," she said. "We're the two mechanics on the flight . . . . We can replace cathode ray tubes and change computers. I actually knew how to do that before, because I had to know how to do that for the capcom capsule communicator job."

Ride fingered a blue canvas hammock dangling from one wall of the living quarters.

"This is a sleeping bag," she said, "but it's not obvious that we need sleeping bags. We probably won't use them." Astronauts on past flights have often opted not to use the vertically suspended bags, preferring to sleep in seats in the cockpit or anchor themselves to floor or walls with tape or string so they will not float around the cabin.

In the middle of the cabin floor was the portable treadmill that can be anchored there when astronauts want to exercise. Straps called bungees fit over the shoulders to hold the astronaut in place and exert resistance to mimic gravity, so the exercise requires muscular effort.

"This is an access way up to the flight deck that you can float up," Ride said, pointing to a hole in the ceiling lined with white canvas. "We're supposed to keep our spacesuits here, but we're not going to. We'll keep 'em somewhere else. The most fun Crip had on his previous shuttle flight was floating to and from mid-deck, and he says we need to have that kind of fun, too."

A ladder led to the flight deck by a different route. Inside, large seats for the commander and pilot faced the small front windows, framed by a maze of instruments, keyboards, four computer display screens and panel upon panel of switches. Taped between the switches were typed cards with sequences of instructions in case of malfunctions.

Smaller seats swiveled out of the wall at the rear of the flight deck for the mission specialists, and large ceiling windows were designed to provide a view of the Earth, normally overhead when the shuttle is in orbit. Rear windows looked out over the mockup's cargo bay, the enormous deck where satellites and other experimental equipment are stored. During orbit, the roof of the cargo bay is open to the sky and Earth above.

Scrambling down the ladder to the mid-deck, Ride exclaimed, "And I forgot to show you this, the WCS."

The WCS, or waste collection system, is the toilet that makes it possible for the shuttle to accommodate astronauts of both sexes. Housed in a closet in one wall of the living quarters, it operates by air suction and looks much like an airplane lavatory. "Supposedly, it works pretty well," she said.

During Ride's training, every aspect of the mission was broken down into components and rehearsed, first in the classroom or in the shuttle mockup, which looks like the real thing but does not contain working computers. Later it was done in the simulator, in which all switches connect to computers programmed to create potential in-flight situations.

The astronauts' most elaborate and stressful training took place during "integrated sims," sessions in which all of Mission Control is staffed with engineers and programmers who work with the crew in the simulator as if they were in space.

During these sessions, which can last as long as 56 hours and may cover the events of an entire flight, programmers called "sim sups" simulation supervisors throw in failures affecting every shuttle system. That is to test not only the astronauts but also hundreds of engineers monitoring the flight on the ground.

Overseeing each system is an engineer at a console in the Space Center's Mission Control room, using radio communication and a computer terminal to track ever-changing data on such topics as the shuttle's altitude, speed and coordinates, its electrical and environmental equipment, the state of its engines and fuel supply, and weather conditions.

Each system's representative, known by acronyms such as "FIDO" or "EECOM, communicates over radio headsets with the flight director, who makes all decisions regarding the flight. Beside him, the capsule communicator radios instructions to the astronauts.

In one four-hour integrated simulation, during which the STS7 crew and its ground support team were practicing shuttle landings, there were fuel and oxygen leaks, computer and electrical failures, communications foulups and speed-brake malfunctions. After each practice landing, astronauts and engineers discussed their performance by radio with the flight director and the "sim sup."

During one debriefing, Crippen remarked, "In the real world, we would have debated that decision a little bit more."

"I guess I'm hearing words that bother me slightly," the simulation supervisor replied, "and that's 'in the real world' versus the simulation . . . . When we script a case, we script everybody, and we try to predict what the real reaction would be."

The goal of integrated simulations is to prepare for every possible failure before a flight takes place, according to Bryan O'Connor, an astronaut who served as a capcom during the fifth shuttle flight. "It all fits into the game," he said. "They play it very realistically here."

At times, the players react as emotionally as they would during a real flight. O'Connor said that during one 56-hour simulation of the fifth flight the shuttle crew tried without success throughout the first day to launch the SBS satellite.

On the morning of the second day, he said, "The crew came on the radio and said . . . ,'We got the SBS up!' . . . This whole Mission Control room broke into cheers."

He said that even though the programmers create thousands of possible malfunctions, they have learned over the lifetime of the space program that they cannot always second-guess fate.

"The best example of something that had never been simulated was on Apollo 13," he said. "They had an explosion of the oxygen tank in the command and service module . . . . The thing blew up on the way to the moon. It turned out oxygen and water were the two consumables that suffered."

The accident meant that the planned moon landing could not take place, and left crew members unsure whether they would have enough oxygen and water to return to Earth.

They decided to use the lunar module as a life raft," O'Connor said. Lights, heat and other life-support systems were turned down as low as possible.

"The crew were miserable, but they survived," he said. "The public has long since forgotten this, but they haven't forgotten it here. The public thinks Apollo 11 first man on the moon was the triumph of the space program. As far as this room is concerned, Apollo 13 was."

Despite the memory of Apollo 13, most astronauts regard integrated simulations as worst-case scenarios, laced with more failures than any real flight would have. Asked after the landing simulation about one computer scenario that would have made it impossible to land, Crippen laughed and said, "They can always give you enough failures that the plane will crash."

On a clear blue Texas afternoon, Ride drove to Ellington Air Force Base for a rare break in the routine and tension of shuttle training. She changed into a well-worn blue flying suit, nipped in at the waist, with a NASA insignia and a space shuttle patch on the sleeve. She laced her brown flying boots.

Ride dialed a number from the base office to get a weather report, and another number to file a flight plan to Barksdale, a base near Shreveport, La. Then she picked up her light blue flying helmet and her parachute from their hooks in the parachute room reserved for astronauts and strolled across the field to No. 907, one of NASA's sharp-nosed, little T38 jets.

John Fabian arrived, suited up. Ride climbed into the rear cockpit seat and Fabian into the front as mechanics made final adjustments. Then the engines roared, and the slender white jet began to roll slowly toward the far end of the field. Ride, wearing her helmet and oxygen mask, waved as it with the flight director, who makes all decisions regarding the flight. Beside him, the capsule communicator radios instructions to the astronauts.

In one four-hour integrated simulation, during which the STS7 crew and its ground support team were practicing shuttle landings, there were fuel and oxygen leaks, computer and electrical failures, communications foulups and speed-brake malfunctions. After each practice landing, astronauts and engineers discussed their performance by radio with the flight director and the "sim sup."

During one debriefing, Crippen remarked, "In the real world, we would have debated that decision a little bit more."

"I guess I'm hearing words that bother me slightly," the simulation supervisor replied, "and that's 'in the real world' versus the simulation . . . . When we script a case, we script everybody, and we try to predict what the real reaction would be."

The goal of integrated simulations is to prepare for every possible failure before a flight takes place, according to Bryan O'Connor, an astronaut who served as a capcom during the fifth shuttle flight. "It all fits into the game," he said. "They play it very realistically here."

At times, the players react as emotionally as they would during a real flight. O'Connor said that during one 56-hour simulation of the fifth flight the shuttle crew tried without success throughout the first day to launch the SBS satellite.

On the morning of the second day, he said, "The crew came on the radio and said . . . ,'We got the SBS up!' . . . This whole Mission Control room broke into cheers."

He said that even though the programmers create thousands of possible malfunctions, they have learned over the lifetime of the space program that they cannot always second-guess fate.

"The best example of something that had never been simulated was on Apollo 13," he said. "They had an explosion of the oxygen tank in the command and service module . . . . The thing blew up on the way to the moon. It turned out oxygen and water were the two consumables that suffered."

The accident meant that the planned moon landing could not take place, and left crew members unsure whether they would have enough oxygen and water to return to Earth.

They decided to use the lunar module as a life raft," O'Connor said. Lights, heat and other life-support systems were turned down as low as possible.

"The crew were miserable, but they survived," he said. "The public has long since forgotten this, but they haven't forgotten it here. The public thinks Apollo 11 first man on the moon was the triumph of the space program. As far as this room is concerned, Apollo 13 was."

Despite the memory of Apollo 13, most astronauts regard integrated simulations as worst-case scenarios, laced with more failures than any real flight would have. Asked after the landing simulation about one computer scenario that would have made it impossible to land, Crippen laughed and said, "They can always give you enough failures that the plane will crash."

On a clear blue Texas afternoon, Ride drove to Ellington Air Force Base for a rare break in the routine and tension of shuttle training. She changed into a well-worn blue flying suit, nipped in at the waist, with a NASA insignia and a space shuttle patch on the sleeve. She laced her brown flying boots.

Ride dialed a number from the base office to get a weather report, and another number to file a flight plan to Barksdale, a base near Shreveport, La. Then she picked up her light blue flying helmet and her parachute from their hooks in the parachute room reserved for astronauts and strolled across the field to No. 907, one of NASA's sharp-nosed, little T38 jets.

John Fabian arrived, suited up. Ride climbed into the rear cockpit seat and Fabian into the front as mechanics made final adjustments. Then the engines roared, and the slender white jet began to roll slowly toward the far end of the field. Ride, wearing her helmet and oxygen mask, waved as it passed.

The plane waited at the end of the runway, its engine a faint hum, and at last it came shooting along in a white blur.

It lifted smoothly like a wild swan and passed through cloud shadows, one wing tilting in a wide, graceful arc. Then it rose, crossed the sky in the east and faded to nothing. graphics/1 photo: Astronaut Sally Ride climbs from cockpit of shuttle replica, the 1G trainer. By Lucian Perkins--TWP graphics/2 photo: As an astronaut candidate, Sally Ride tries out an ejection seat in a training exercise at Vance Air Force Base in Oklahoma. She was selected as a crew member on the shuttle flight scheduled for June 18. graphics/3: Emblem of the June 18 mission passed.

The plane waited at the end of the runway, its engine a faint hum, and at last it came shooting along in a white blur.

It lifted smoothly like a wild swan and passed through cloud shadows, one wing tilting in a wide, graceful arc. Then it rose, crossed the sky in the east and faded to nothing.