First flight of the Pathfinder 21 was in 1995. After Soloy cancelled the 19 seat project, it sat mostly idle at Olympia, WA after 1999. This is all that remains of the prototype conversion after parting out.

The Soloy Pathfinder 21 was a conversion of a Cessna 208B powered by the Soloy Dual Pac (two side-by-side P & W PT-6 engines driving a single propeller) developed with Pratt & Whitney Canada. A 72 inch fuselage extension aft of the wing and extra capacity for cargo or baggage under the fuselage were other modifications. Soloy abandoned the program when the FAA required it be certified under FAR 25 (Transport category) requiring higher airframe strength that would be too expensive if not impossible to implement.