Photos by Eric Brady | The Roanoke Times

Investigators' vehicles are clustered at the edge of a field at Virginia Tech's McCormick Farm in Rockbridge County on Sunday near the spot where a Pilatus single-engine aircraft went down.

Todd Gunther (center, facing camera), an investigator with the National Transportation Safety Board, talks with Virginia State Police and other local personnel on Sunday near the crash site.

At least two people were killed in a plane crash Sunday morning in Rockbridge County after the pilot reported an equipment failure and diverted to Lynchburg Regional Airport, a Federal Aviation Administration spokesman said.

Authorities did not identify the occupants. But a son of the family that owns the aircraft said his parents, Daniel and Cynthia Dorsch, were scheduled to fly in the plane on Sunday. Daniel Dorsch is a former CEO of Checkers Drive-In Restaurants and a business owner in central Florida.

The Pilatus PC-12, a single-engine aircraft, crashed about 10:30 a.m. Sunday after departing from Teterboro Airport in northern New Jersey about 7:30 a.m. for Tampa Executive Airport in Florida, FAA spokesman Jim Peters said. The plane crashed on McCormick Farm, which is owned by Virginia Tech.

"The pilot told air traffic control that an exterior panel came off the exterior of the aircraft," Peters said. The pilot said he was diverting to Lynchburg.

The National Transportation Safety Board is leading the investigation with aid from the FAA, the Virginia State Police and local jurisdictions.

The state police dispatch center in Salem received a call from a resident about a plane in distress at 10:06 a.m., spokesman Sgt. Rob Carpentieri said.

The plane was flying at an altitude of 26,000 feet and climbed to 32,000 feet shortly before the crash, said Todd Gunther, an NTSB investigator. The aircraft later dropped off the radar.

Gunther said in a news conference Sunday afternoon that NTSB officials would interview witnesses to the crash as part of a field investigation, and that a preliminary report would be issued in the following days. He said a factual report would follow in nine months.

Nearby residents Bruce Holden and Jennifer Ramsey said they heard what sounded like an engine being revved up. Holden, who lives about a mile and a half from the farm, said he heard the sound of an engine winding up, and then it sounded like it was "getting ready to blow."

Ramsey said she heard what sounded like a motorcycle engine being revved up and down. Then, she felt her house shake.

"I thought my oak trees hit the house," she said. Minutes later, she heard sirens.

McCormick Farm is an agricultural research and extension center and is nestled in a rural area with woods and rolling hills. A few homes are nearby.

The plane was registered to Nicholas, Elliott & Jordan LLC, a company with a Tampa address, according to online records. The principal of the corporation, Daniel Dorsch, is a licensed pilot.

Jordan Dorsch said his parents were scheduled to fly the Pilatus PC-12 his father owns from New Jersey to Florida on Sunday. He said they had not arrived at the airport hours after they were expected and that he had been unable to contact them.

Daniel Dorsch served as CEO of Checkers from 1999 to 2003. Dorsch now owns businesses in central Florida, including several Papa John's Pizza outlets and Fun Bike Center Motorsports.

According to media reports, Dorsch has donated to causes such as the family of a Tampa-area high school quarterback who was killed in a car crash in May.

Multimedia producer Jordan Fifer and news researcher Belinda Harris contributed to this report.