The five-man crew of the shuttle Discovery waited out bad weather and then rocketed flawlessly into orbit Monday to deploy a $100 million NASA communications satellite and carry out a series of experiments.

Discovery, carrying four deliberately injured rats and 32 chicken eggs for student projects, blasted away with a thundering roar at 9:57 a.m., one hour and 50 minutes behind schedule because of heavy fog and concern about high-altitude wind along the shuttle's flight path.The 4.5 million-pound space freighter majestically climbed away from launch pad 39B, trailing 600-foot tongues of incandescent flame and thrilling thousands of spectators jammed along Florida's "space coast" as it arced east over the Atlantic Ocean and streaked toward space.

At the controls were commander Michael Coats, 43, and John Blaha, 46. Also on board were astronauts James Bagian, 37, Robert Springer, 46, and James Buchli, 43. All five were decked out in bulky, bright-orange spacesuits that are part of a new post-Challenger emergency bail-out system.

Discovery's three main engines shut down on schedule 8 1/2 minutes after blastoff and the orbiter separated from its external fuel tank, achieving a safe elliptical orbit.

Coats and Blaha fired Discovery's two big maneuvering rockets 40 minutes later to circularize the orbit at an altitude of 184 miles. The crew then opened the shuttle's payload bay doors, exposing their satellite payload to space, and received a formal "go" for orbital operations from mission control in Houston.

At the White House, President Bush watched the launching on television and apologized for getting to a meeting late, saying, "I just couldn't pull myself away from watching the Discovery."

"It was great!" said astronaut David Hilmers, a veteran of Discovery's Sept. 29 launch on the first post-Challenger flight. "It was beautiful."

"This is the kind of Monday to start a week on," said launch director Robert Sieck.

J.R. Thompson, director of the Marshall Space Flight Center in Huntsville, Ala., said, "I'm not worried about any problems right now. All of the engine data looked very nominal. We're not aware of any propulsion problems at all and not any total vehicle problems at all."

As Discovery completed its first orbit, flying back over Florida, Coats took time to thank technicians at the Kennedy Space Center for a good job replacing the shuttle's liquid oxygen turbopumps - work that delayed launch more than two weeks.

"It seems like a fitting time as we're passing over Florida . . . again to tell some of the main engine people they did . . . a good job getting our engines in shape here," he said. "Well done from all of us. We sure appreciate all the good work they did getting the engines in shape and ready to go. They sure worked well."

Earlier, after separation from the external tank, Coats rolled the orbiter over so it could be photographed. The shuttle Atlantis suffered major tile damage during the second post-Challenger launch Dec. 2, possibly caused by debris falling from its tank and boosters.

"We saw a few things come off at . . . about 50 seconds that made some smears on the windows," Coats said. "Now that we're pointed down to the Earth, it's just beautiful. We can see a few smudges on the windows. Looks like bug smudges."

The primary goal of the five-day mission was the deployment of a giant $100 million Tracking and Data Relay Satellite - TDRS - six hours and 12 minutes after blastoff. The satellite, working with another such relay station already in orbit, will allow NASA to stay in near-constant contact with future shuttle crews.

Launch of the 28th shuttle mission, the third since the 1986 Challenger disaster and the first of seven planned for 1989, came more than three weeks behind schedule because of a series of technical problems, including the replacement of all three of the ship's high-pressure liquid oxygen turbopumps.

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Retrieval ships spot boosters

Discovery's two solid booster rockets splashed into the Atlantic Ocean 160 miles offshore right on schedule Monday after guiding the shuttle toward orbit.

"The boosters are in the water within sight of the retrieval ships," said Michael Hardee, who works at NASA's Marshall Space Flight Center in Huntsville, Ala. "It'll be a while before they get close to them and start retrieving them."

It takes more than 24 hours before the casings of the rockets, which are used again, can be towed to shore for close inspection.

The solid rocket boosters separated from the shuttle two minutes, six seconds after liftoff and hit the water about five minutes after that.