The pilot of the twin-engine Beachcraft Bonanza was from Texas and had flown to Santa Rosa Tuesday, returning to Texas on Wednesday with two men and a woman on board, Navajo County sheriff's Commander Bob Sutton said.
He had stopped for fuel at Holbrook Municipal Airport in Arizona on the way to Santa Rosa on Tuesday, and also on Wednesday just before the plane crashed, Sutton said.
But he said the pilot had become ill by the time he returned for fuel.
"He must have caught something in California because the guy at the airport who talked to him while he was returning to Texas said he had been puking," he said.
The pilot apparently decided to lie down while the other three went out for a bite to eat in Holbrook.
Shortly after they took off again, the freshly fueled plane caught fire and crashed about a quarter-mile east of the airport in a desert area, according to the Federal Aviation Administration.
Sutton said there is no way to tell if the pilot's illness had anything to do with the crash.
"Autopsies have to be done before they'll ever determine that, if they can even determine that. We may never know," he said.
Since the pilot was from Texas and the flight was only for a day, Sutton said authorities are assuming the passengers were also from Texas.
He was not sure why they went to Santa Rosa or if the same people were on the returning flight.