PA-23-250 Aztec is a light multipurpose aircraft developed by the American company Piper Aircraft Inc. The aircraft is an evolution of the PA-23 Apache model. An improved six-seater variant with a Lycoming O-540 250 hp engine. produced under the designation RA-23-250 Aztec, in 1959-60, the US Navy purchased 20 aircraft, giving them the designation UO-1, which was changed to U-11A in 1962. Aztec aircraft were produced until early 1982. In the final serial configuration - the designation RA-23-250 Aztec F, there was also a similar model RA-23T-250 Turbo Aztec F.