Midshipman Timothy Powell Scott, 18, a resident of Potomac and a first-year student at the U.S. Naval Academy at Annapolis, died Friday in Carroll County General Hospital in Westminster, Md., of injuries suffered in an auto accident that day.

A spokesman for the Maryland State Police said Mr. Scott was traveling east at a high rate of speed on Rte. 26 in Eldersburg when his car ran off the right side of the road and struck a utility pole, a fence post and the porch of a house.

Police said they believed Mr. Scott and his two passengers, Midshipmen Richard Michael McBride, 19, of Houston and Brett James Muilenburg, 18, of Titusville, Fla., had been drinking before the accident.

McBride and Muilenburg, classmates of Mr. Scott at the Naval Academy, were treated in area hospitals and released.

Mr. Scott was born in San Francisco and came to Potomac with his family in 1963. In 1975, he accompanied his family to Hawaii. The family returned to Potomac and Mr. Scott entered the Naval Academy in the autumn of 1980.

He played varsity soccer and football at Iolani High School in Honolulu and was a member of the varisty soccer team at the Naval Academy.

Mr. Scott was the third generation of his family to attend the Naval Academy.A grandfather, the late Capt. Edward E. Hazlett, was a member of the class of 1915. Mr. Scott's father, former Navy Lt. Richard Underhill Scott, was a member of the class of 1948.

In addition to his father, of Potomac, Mr. Scott's survivors include his mother, Elizabeth Hazlett Scott, and one sister, Polly Super, also of Potomac; one brother, Peter, of Bethesda, and a grandmother, Elizabeth Hazlett of Chapel Hill, N.C.

The family suggests that expressions of sympathy be in the form of contributions to the Naval Academy Foundation Inc., Annapolis.