He was the scion of one of the oldest and wealthiest families in Gaithersburg, an heir to an automobile dealership fortune who at age 29 had risen from floor sweeper in his father's showroom to general manager of that multimillion-dollar car business.

Robert Victor Aschenbach's life was as charmed as he himself was charming, his close friends recalled yesterday. After all, they said, only "Robbie" could walk away from a spectacular accident last year that occurred while he was indulging in his favorite passion, race-car driving.

But on Wednesday night, about a half hour after closing his father's King Pontiac showroom at 10 p.m., Aschenbach lay on the floor of a Rockville nightclub, the casualty of a barroom brawl he had tried to break up. Several hours later, he had died of a skull fracture, authorities said.

Montgomery County police have charged Timothy Robert Doyle, 33, of 18446 Stone Hollow Dr. in Gaithersburg in Aschenbach's death, according to police spokesman Phillip B. Caswell. It was Doyle who knocked Aschenbach to the floor of J.J. Muldoon's, a new Rockville restaurant, police said.

Aschenbach was injured in the fall but remained conscious and later died in the foyer of his home in the exclusive Spring Meadows Estates subdivision of Montgomery, police said. Doyle was released on a $50,000 bond after his arrest late Thursday, police said.

Aschenbach's death stunned many in Gaithersburg, a city of 26,000 that counts Aschenbach's maternal grandfather, Lawson King, among its founding fathers.

"It's almost unbelievable because Robbie was such a vibrant young guy," said Gaithersburg Mayor Bruce A. Goldensohn, who knew Aschenbach for years. "He was never known as being a roughneck or ever in any kind of trouble."

Through a spokesman, members of Aschenbach's large family declined to comment on his death. But others who knew him recalled Aschenbach as a "natural" businessman who would almost certainly have inherited a large part of his family's fortune.

Robert Aschenbach was born to wealth but never flaunted it or his family's own prominence, his friends said yesterday. Lawson King, his grandfather, owns a huge cattle farm and a block of stores in Gaithersburg's old section, while Conrad V. Aschenbach, his father, owns two car dealerships, including the King Pontiac business, where the property alone is valued at over $3 million, according to county records.

The younger Aschenbach, whose own home was assessed at $216,200, enjoyed the good life, working 12- and 14-hour days at the family's business and spending weekends racing a $50,000 Trans Am racer, his friends said.

"With Robbie, though, you never had the feeling you were dealing with a millionaire," said Goldensohn, who recently bought a car from his friend. "Although he was the kid who got the job at Daddy's store, it was obvious he had a talent for business."

Aschenbach rapidly moved up through used-car and new-car sales to become general manager of King Pontiac, said Phil Dorsey, a close friend and a King Pontiac manager. "Robbie made the whole atmosphere of the place," said Dorsey. "His whole life was the car business. Everybody knew eventually it would be his."

Dorsey and Aschenbach worked together until 10 p.m. Wednesday, said Dorsey, and after closing the storeroom Aschenbach and another friend stopped for a drink at J.J. Muldoon's, two blocks away. Details of the altercation at the restaurant remained sketchy yesterday, but Aschenbach apparently was knocked to the floor as he tried to break up a fight, according to Dorsey and a spokesman for the nightclub. Aschenbach's companion, identified as L.C. McCutcheon, the administrative officer of the Gaithersburg Fire Department, could not be reached for comment.

Aschenbach was still conscious at the bar but passed out as he was driven home by a friend, police said. Aschenbach apparently walked into his house by himself. A family member found him laying face down in the house foyer at 7:45 a.m. Thursday, police said.

Doyle was arrested at his home Thursday night and charged with murder, Caswell said. Doyle was unavailable for comment.

Aschenbach is survived by his parents and two brothers and two sisters, who worked with him at their father's car dealership. A memorial service is scheduled for 2 p.m. today at Epworth United Methodist Church.