N2GP Inside the hangar at Planes of Fame Air Museum. The sleek Duke was introduced by Beech in 1968, aimed at the owner-flown segment of the business aircraft market. It was powered by a pair of 380hp Lycoming TIO-541 six cylinder turbocharged engines driving Hartzell three-blade propellers. This Duke Model 60 was built in 1969 and is one of about 125 built. Owners found the engines expensive to overhaul and maintaining the aircraft was likened to a high-end sports car. Later models included the A60 and B60 with modified turbochargers and cabin pressurization. (mehr von N2GP)