Aircraft
Walter-powered King Airs, a better idea?
Dan Sigl, president of Seagull Aviation in Clintonville, Wis., has invested a significant portion of his career in Walter 601-powered derivatives of existi

Dan Sigl, president of Seagull Aviation in Clintonville, Wis., has invested a significant portion of his career in Walter 601-powered derivatives of existing airframes, specifically the Beech King Air series. The story of converting C90s to Walter power has its share of twists and turns, and the saga is far from over.

Sigl and his Wisconsin shop are associated with Performance Conversions of Incline Village, Nev., holder of the STC under which the aircraft in the accompanying pilot report was converted to Walter power. Robert Turnage is the managing director of Performance Conversions. Sigl’s shop is also at work on a new STC for the King Air 100 and also has a de Havilland Twin Otter project currently on the back burner. Another unrelated company, Lone Star Propjets of Waco, Texas, also has a separate STC for converting King Air 90s to Walter power.