Pacific Air Transport and United Air Lines Transport Corporation (airlines) (defendants) operated airplanes that regularly flew over property owned by Hinman (plaintiff). Hinman brought suit against each airline for trespass, alleging that he had title to the airspace above his property of a height ranging from at least 150 feet to an indefinite distance, and that the airplanes had flown less than 100 feet above his property. Hinman sought an injunction preventing the airplanes from flying over his property, in addition to $90,000 in damages from each airline. The district court sustained each airline’s motion to dismiss. Hinman appealed to the United States Court of Appeals for the Ninth Circuit.