05/15/2013. Remarks by Johan Visschedijk: "The Duet, known originally as the Minor III, is a side-by-side two-seat version of the Luton L.A.4A Minor, developed originally by Group Captain Alfred Stanley Knowles in association with the former Phoenix Aircraft Ltd. Design began in 1968 and registered G-AYTT on March 4, 1971, the prototype Duet flew for the first time two years later, on June 22, 1973. A special category CofA was granted on June 24, 1974.

During 1976 shaped wing tips were developed for the Duet, and flight testing with these began in early 1977. The new tips increased the wing span, and resulted in reduced stall speed, increased rate of climb and improved gliding angle.

A second example was built by Colin Woods, registered G-DUET (c/n D.001) on December 19, 1978, it was deregistered on April 30, 2002."