The son of a former Virginia governor was one of two persons who died Sunday when their home-built airplane crashed minutes after takeoff from an airport in Fauquier County, authorities said yesterday.

Pilot Albertis Sydney Harrison III, 57, of Prince William County, and passenger Mary Celeste Lobi, 43, of Fairfax Station, died instantly when their craft went down shortly before 4 p.m. Sunday in a field near Morrisville, Va., the Virginia State Police reported.

Harrison's father, Albertis S. Harrison Jr., was governor from 1962 to 1966 and is a retired justice of the state Supreme Court.

The cause of the crash was not immediately known. The National Transportation Safety Board and Federal Aviation Administration were continuing their investigation yesterday.

Officials said the plane, worth about $120,000, was destroyed.

Officials described the home-built Glassair plane that Harrison had been flying as a popular, high-performance craft that can be built from a kit. The plane had been approved for flight by the FAA. Harrison was listed as its second owner.

Ben Owen, a spokesman for the Experimental Aircraft Association, said more than 10,000 small planes built from kits or from plans are in use in this country, not counting one-person "ultralight" craft.

Owen said home-built planes have a safety record roughly equal to factory-built small craft.

Safety Board spokesman Michael Benson said witnesses reported seeing the plane reach an altitude of about 2,000 feet before descending abruptly and spinning into the ground.

State police spokeswoman Lucy Caldwell said weather was good at the time of Sunday's crash.

She said four small planes have had accidents in the state since Thursday, noting that use of small craft typically increases in the spring.