07/31/2009. Remarks by Walter van Tilborg: "The DA-9 of Leeon Davis was one of many original designs which were all characterized by the V-tail. Davis was a very active designer with some 11 subsequent designs in his name (only the DA-10 was not built and the DA-4 was completed as DA-2C). The DA-9 was not intended for amateur construction, but mainly built as engine test bed.

Work on the DA-9 started in 1986 and when first flown on May 25, 1990 the aircraft had a 40 hp two-cylinder engine which was basically a "half" Continental A65. In 1995 the DA-9 was re-engined with a 90 hp Continental C90 and the aircraft was then also used to establish several FAI climb-to-altitude records."