Midshipman First Class Michael R. Olmstead, the first U.S. Naval Academy student to be court martialed since 1922, was found guilty of involuntary manslaughter today in the car accident death of his Academy roommate and closest friend.

Olmstead, a shy 21-year-old senior, stood at attention, his hands clenched at his sides, as Capt. Neuland Collier delivered the verdict in a makeshift courtroom here draped in green felt.

"It is my duty as president of the court," Collier read in clipped tones, "to inform you that the court . . . finds you guilty of the charge in the specification."

With those words, Olmstead's face drained of color and his shoulders slumped. His parents, seated behind him, had tears in their eyes. Their son, who had dreamed of a naval career since kindergarten, now faces possible expulsion.

Olmstead was accused of drinking, driving and recklessly causing the death of his friend, Midshipman Scott Thomas, who was 20 at the time of the accident last May 11. The two were returning from a night on the town and just crossed Dorsey Creek Bridge on Academy grounds when Olmstead's Porsche sports car veered off the road and slammed into a tree. Thomas was thrown to his death.

Tonight, moments after the verdict, Olmstead stood somber and mute as his attorney, Lt. Cmdr. John Holt, read a statement to the press for his young client.

"Today my first thoughts are with the family of midshipman Scott Thomas. Scott was my closest friend at the Naval Academy. I am very sorry he was killed . . .," Holt read.

"This case involves a tragic car accident. Abuse of alcohol was involved . . . I hope others, particularly midshipmen who have followed my case, may have learned something from my personal tragedy and can avoid a similar accident."

Olmstead must return to the same courtroom Monday to face sentencing by the six officers who found him guilty. The maximum penalty, along with expulsion, would include forfeiture of all pay and benefits and three years in prison.

"We will have to leave ourselves to the mercy of the court," Olmstead's father, Leroy, said as the family left the Academy's darkened grounds, emptied by the midshipmen's spring break.

Despite the possible penalties, Olmstead, who has kept up with his classes here and is within months of graduation, said in his statement, "I maintain my desire to graduate from the Naval Academy and become a Naval officer."

Although it is possible for the jurors to allow him to remain at the Academy, legal observers said that would be an unusual decision because most servicemen found guilty of a serious offense are discharged.

For the past two weeks, Olmstead has watched as the prosecutor, Lt. David Acton, asked the jury to find him guilty of gross negligence. Acton asserted that Olmstead was intoxicated, insisted upon driving and did so at speeds so high that he could not have negotiated the curving road even if he was "stone, cold sober."

The defense pinned its hopes on raising a doubt in the jurors' minds about who was actually driving.

Olmstead's attorney Holt contended that no one -- not even his client, who was lapsing in and out of an alcohol-induced blackout -- could say with certainty who was behind the wheel. There were no witnesses to the accident. Furthermore, Holt argued that the smash-up was purely and simply an accident at an "inherently dangerous" intersection.

As the two sides battled, Olmstead became an unlikely and reticent celebrity here, a piece of history in this enclave of granite tradition. It has been 58 years since a midshipman was court martialed, and in that 1922 case the charge was hazing a plebe. The defendant was found guilty, but the verdict was later reversed.

Olmstead, too, has a right to appeal, first to the academy's superintendent, Vice Adm. William Lawrence, and then on through the military appeals courts.

Tonight, in his statement, Olmstead had only glowing words for Lawrence and the academy. "I have had an excellent first semester this year," his statement said, "and continue to make plans for a career in the service of the Navy.