The SAI KZ I was a sport aircraft built in Denmark in 1937, the first aircraft built by the Kramme & Zeuthen firm.
The KZ I was a low-wing cantilever monoplane of conventional design, with fixed tailwheel undercarriage and an open cockpit with a single seat. Construction throughout was of wood.
Only a single KZ I was constructed, and it disappeared during the course of World War II. During the 1970s, a flying replica was built, with work started by Gunnar Fjord Christensen in 1972 and sold to the Danmarks Flymuseum in 1977. The completed aircraft, powered by a more powerful but heavier, Volkswagen flat-four engine, flew for the first time on 20 November 1988 and in 2008 remains part of the museum's collection.