It was registered as CF-BZY to Canada Veneers Ltd. of Saint John, New Brunswick on October 29, 1945, then exported to the USA in May, 1951 as registered first as N36992, later N3692, and later exported to Britain where it was registered as G-ASXG to the Grosvenor Estates on October 8, 1964. By that time the underwing floats had been replaced by retractable wing-tip floats.
On July 26, 1968 it was converted to a turboprop aircraft by Marshall of Cambridge, UK. Two 550 shp Pratt &Whitney Aircraft of Canada PT6A-20 turboprop engines replaced the original 450 hp Pratt & Whitney R-985 Wasp Junior nine-cylinder, air-cooled radial engines, while also a radar-nose and wrap-around wind screens were fitted.
The original G-21 and G-21A types were produced and certified under Type Certificate (TC) 654. Any alteration to the aircraft's certified layout needs an Supplemental Type Certificate (STC), for TC 654 there are 64 STCs, including one to install the two 550 shp PT6A-20 engines. An aircraft altered under an STC does not have to be re-certified and therefore does not legally receive a different designation.
Initiated by Angus McKinnon, the company and the FAA referred to the STC-covered conversions as a Grumman G-21A Hybrid or Grumman G-21A Turboprop, while the media used McKinnon G-21 Turbo-Goose as a designation. After the conversion, for which a McKinnon-supplied STC-covered kit was used, G-ASXG was technically still a Grumman G-21A, covered by the original TC 654, as confirmed by a representative of the current owner of the McKinnon type certificate.
It was re-imported into Canada in 1973 as C-FAWH and Dave Hilchie adds:
"I took this snapshot when I was working for Air West Airlines at Vancouver as a mechanic. We had just completed several months work on the aircraft that included stripping out the executive interior and installing high density passenger seating (10 seats), reversing the engine intake scoops from the bottom to the top of the nacelles, extensive avionics replacements and associated wiring and a complete exterior paint stripping and repainting in the Air West colors of basic white with black, red and orange trim."
Reportedly the aircraft was sold in 1978 to Provincial Airlines at Prince Rupert, and by 1986 it was owned by Jim Pattison Industries (also at Prince Rupert), while it had been reconverted to R-985 engines. It was sold to Air Bc Limited of Richmond before it was written off in a water landing accident on May 12, 1988. The remains were still in the bone-yard at Port Hardy Airport, British Columbia in November 2006."