Members of a Rockville family flew the Stars and Stripes from a pole in their front yard yesterday as they awaited news of their Navy son, lost with eight others when a Navy jet went down near Guam on Wednesday.

No sign of the plane or the nine persons on board has been found since it went down in fair weather about 130 miles from the west Pacific island. But navigator Lt. j.g. Richard A. Thomson remains alive, his family believes, and will soon be calling home.

"He's a stubborn son-of-a-gun," his father, Donald Thomson said yesterday as he, his wife and older son gathered with friends and relatives. His father, himself a Navy veteran, said his 26-year-old son was born in Guam, and has been based there for more than a year.

Neighbors, friends and relatives gathered yesterday at the Thomsons' house on Bradley Avenue to comfort each other. The Thomsons tried unsuccesfully to contact relatives of the other area man lost in the crash, identified by the Navy as Petty Officer Thomas J. Jorgensen, 23, of Fairfax.

Navy officials said the plane, a VA-3-B two-engine jet, disappeared from radar screens on Wednesday but refused to speculate on what caused it to go down.

Navy spokeswoman Lt. Roberta Hackney in Guam said the search, involving several Navy and Coast Guard ships and aircraft, was continuing.

"If the plane made it to the water safely, all aboard stand an excellent chance of being alive," Hackney said. She said the plane, on a flight from Japan to Guam, was equipped with survival gear and that all aboard had received survival training.

According to the Navy, the type of jet lost carries a crew of three, and up to six passengers. A modification of the A-3 Sky Warrior attack bomber, it can land on aircraft carriers and is typically used for pilot training and ferrying passengers and aircrew.

Thomson, who is unmarried, attended Rockville High School and joined the Navy after graduating from Shepherd College in West Virginia.

"He loves his work," his older brother Donald Jeffrey Thomson said yesterday. "And even if he's gone, we do know that he died doing something that he loved. Except that he's not dead."