Howard Plagens of the National Transportation Safety Board said Monday that his team will also look at the time it took emergency crews to respond.
Witnesses have said it seemed like a long time before fire crews arrived at the scene of Sunday's crash at Travis Air Force Base in Fairfield.
The crash killed 77-year-old pilot Edward Andreini of Half Moon Bay. No spectators were hurt.
Base spokesman Jim Spellman disputed witness accounts, saying crews were dispatched promptly and responded within a minute or two.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
A pilot who had thrilled audiences for decades with acrobatic stunts was killed when his vintage biplane crashed upside-down on a runway at a Northern California air show.
Sunday's tragedy brought to a quick halt the "Thunder Over Solano" show at Travis Air Force Base, which was attended by an estimated 100,000 spectators. No one else was injured.
The Air Force identified the pilot as Edward Andreini, 77, of Half Moon Bay. Federal Aviation Administration records show he was the registered owner of the 1944 Stearman biplane, a World War II-era plane commonly used to train pilots.
Andreini was trying to perform a maneuver known as "cutting a ribbon" where he inverts the plane and flies close to the ground so that a knife attached to it can slice a ribbon just off the ground, Col. David Mott, 60th Operations Group commander at the base, told the San Francisco Chronicle.
Andreini's website said audiences would be "thrilled at the sight of this huge biplane performing double outside loops, square loops, torque rolls, double snap rolls, and ... a heart-stopping, end-over-end tumble maneuver." It said he had flown since he was 16.
The plane, flying low over the tarmac, crashed and caught fire, letting off a thick plume of black smoke seen in video of the aftermath.
Roger Bockrath, a retired photojournalist who was photographing the afternoon show, chronicled the routine and witnessed the crash. He said Andreini, flying into a sometimes gusty wind, passed on two attempts before trying a third time, hitting the tarmac and sliding to a stop in an open field.
"He got down too low and hit the tarmac. He skidded about 500 feet and just sat there. The plane was essentially intact, just wrong side down," Bockrath told The Sacramento Bee.
Bockrath said nearly 2 1/2 minutes went by before someone appeared with a fire extinguisher. By then, the aircraft was fully enflamed and collapsing from the heat. He said it took a total of five minutes before fire crews arrived.
The National Transportation Safety Board is heading up an investigation. Lynn Lunsford of the FAA said the FAA was already on site and will be a member of the team.