California Code, Public Utilities Code - PUC § 21404

Liability of the owner or pilot of an aircraft carrying passengers for injury or death to the passengers is determined by the rules of law applicable to torts on the land or waters of this state, arising out of similar relationships. Every owner of an aircraft is liable and responsible for death or injury to person or property resulting from a negligent or wrongful act or omission in the operation of the aircraft, in the business of the owner or otherwise, by any person using or operating the same with the permission, express or implied, of the owner.