The pilot, identified as Eddie Andreini, 77, of Half Moon Bay, crashed while performing an acrobatic aerial maneuver at about 2:05 p.m., according to the base.
“Local emergency responders told us that the pilot did not survive,” Federal Aviation Administration spokesman Lynn Lunsford said.
The investigation will be handled by the National Transportation Safety Board and the Federal Aviation Administration.
“You could see the flames coming off of it and black smoke as they were waiting for the fire trucks,” a civilian witness told The San Francisco Examiner.
The witness, who did not want to be named, said it appeared the pilot was doing an upside down stunt before crashing.
“I guess [the plane] was too low,” the witness said.
Pilots of both civilian and military aircraft had been performing various aerial maneuvers before a crowd of people when the crash occurred.
The air show last took place at the military base three years ago.
The Federal Aviation Administration and National Transportation Safety Board are scheduled to hold a press conference regarding the crash at 11 a.m. Monday at Travis Air Force Base.
Bay City News Service and The Associated Press contributed to this story.