The Buhl CA-1 Airster was a sports airplane developed in the United States in 1930. It was a conventional low-wing cantilever monoplane with fixed tailwheel undercarriage and an open cockpit for the pilot. The CA-1 was designed for air-racing and for use as a mail plane. No market was found for the aircraft and only the single prototype was ever constructed. A two-seat variant was developed with a second open cockpit in tandem with the pilot's and with a Townend ring and wheel spats, but this didn't sell either.