His friends at the Johnson Space Center call Dr. William E. Thornton the "last angry man," mostly for the way he responds to bureaucratic reasons why things can't be done on space flights.

"Dr. Bill just tells the bureaucrats in no uncertain terms how he's going to do it and then leaves it at that," is the way it's put by an astronaut friend of the oldest American to fly in space. "Bill Thornton doesn't take no for an answer."

There was a time when Thornton, 54, thought he might never fly in space, but the emergence of what is euphemistically called "space adaptation syndrome"--or space sickness--got him a seat on the eighth shuttle flight. Of the 16 shuttle crew members who have flown so far, five have suffered loss of appetite, four had general malaise, five had headaches, four had stomach "awareness," three had nausea and six vomited.

Thornton is in orbit, and in the spotlight, because his colleagues feel he is the nation's foremost authority on space sickness--on what might cause it and what might be done to prevent it.

In the 16 years Thornton has been an astronaut, he has done more to condition his colleagues and keep them well in orbit than anybody else in the program. Thornton designed and built the treadmill that all astronauts use to exercise in space. He designed and built the half-dozen medical electronic devices that astronauts have used to measure body functions in orbit. And he is designing a lower-body-pressure suit that would keep fluids from leaving the legs and moving into the upper torso and head in the absence of gravity.

In a 20-minute televised news conference today, Thornton demonstrated what he is doing in orbit to get a better understanding of the causes of "space-adaptation syndrome." He took his four crewmates one by one and showed viewers on Earth how he is using his instruments to measure their reactions to weightlessness. Thornton's telecast was as much an educational experience as it was a fascinating telecast.

He began by saying that weightlessness produces instant changes in body shape. He said as much as 1 1/2 liters of fluid move from the legs toward the head on the first day a person is in orbit.

Explained Thornton: "It makes our faces rather broad and puffy. In order to study this, we have Dale Gardner here one of the five crewmen modeling the latest in legwear, and this is a stocking that has some special tapes on it which, when pulled into place, may stop that movement of body fluids."

Thornton noted that the shift of body fluids to the head puts pressure on the brain and may be a factor in the headaches some astronauts have suffered in space. The shift in fluids may also have something to do with how the eyes perceive motion and light in space, partially triggering nausea and malaise in some astronauts.

With that, he held up Gardner's leg, displaying a white nylon stocking that extended from ankle to hip, then pulled on several straps to tighten the stocking.

Thornton put Guion Stewart Bluford II, the black astronaut, on the treadmill and directed him to run. Meanwhile, Thornton demonstrated a small tape recorder worn by Bluford to record eye and hand motions, as well as another device--designed by Thornton and worn by Bluford--to record blood pressure and heart rate.

Thornton then called on Cmdr. Richard H. Truly to show instruments that measure how the brain reacts to light stimuli.

"We all know commanders have large brains," Thornton joked, "which is why I'm demonstrating this equipment with our commander Dick Truly."

If anybody can find what causes space sickness, it is probably Thornton. His colleagues describe him as the most intense "workaholic" in the astronaut corps. His friends say he comes to work at 7 every morning and doesn't leave until 7 at night, seven days a week. Said one astronaut: "I've never seen him relax."

Truly makes constant jokes about Thornton's working habits in space. Acknowledging the doctor's hard work on the flight, Truly said at the end of Thornton's telecast today that he and his other colleagues were sick of what he called Thornton's "chamber of horrors."

With that, Truly picked up the hammer and moved across the cabin to where the camera suddenly showed Thornton being held against the bulkhead by the three other astronauts. Taped against the wall like a man about to be crucified, Thornton appeared to be attacked from all sides by knives, wrenches, hammers, even pliers. Turning to the camera, Truly raised the hammer as if to strike Thornton. Then the show faded from the screen and a muffled scream was heard.

Although the oldest astronaut waited 16 years to get into space, Thornton will be there again next year when he joins six other crewmen on the third flight of Spacelab, now scheduled for November, 1984.

Joked one of his colleagues: "He'll make it if he slows down a little and stops working so hard. On the other hand, I don't know how anybody can get him to slow down. I guess he'll make that flight next year anyway."