The Prototype of the Saunders ST-27 was first flown on the 28th of May 1969 in Montreal. The aircraft sign was CF-YBM-X. The photo shows the prototype in front of the Montreal hangar. In winter 1970 the flight test program came to an end. The ST-27 got its canadian type certificate in spring 1971. It was first planned to sell the airplane to canadian Millardair, but it was not taken up. In January 1972 the plane was sold to Aerolineas Centrales de Columbia. It got the sign HK-1286X, later just HK-1286. The HK-1286 in ACES colours In 1976 the airplane got withdrawn from use and was stored. In Juli 1978 the plane returned to the Saunders Company and recieved the sign C-GYCQ. In January 1979 it was sold to Otonabee Airways and finally withdrawn from use in December 1980.