60 - Two 285kW (380hp) Lycoming TIO541E1A4 turbocharged fuel injected flat six piston engines driving three blade constant speed Hartzell propellers. B60 - Two 285kW (380hp) Avco Lycoming TIO541E1C4s.
60 - Max speed 460km/h (248kt), cruising speed 395km/h (214kt). Range with optional fuel and 45 minute reserves 1890km (1020nm). B60 - Max level speed 455km/h (246kt) at 23,000ft, max cruising speed 443km/h (239kt) at 25,000ft, cruising speed 431km/h (233kt) at 25,000ft. Initial rate of climb 1601ft/min. Service ceiling 30,000ft. Max range at 20,000ft with reserves 2078km (1122nm).
60 - Empty equipped 1860kg (4100lb), max takeoff 3050kg (6725lb). B60 - Empty equipped 1987kg (4380lb), max takeoff 3073kg (6775lb).
Standard seating for four with optional fifth and sixth seats and toilet.
Beechcraft built 584 Dukes between 1968 and 1982, including 113 60s, 121 A60s and 350 B60s.
Four or six place light business twin
Between the Beech Baron and Queen Air in size, performance and general capabilities, the Duke was a pioneer in the pressurised high performance light business twin class.
Beechcraft began design work on its new Model 60 in early 1965, with the first flight of the prototype occurring the following year on December 29. US FAA Certification was awarded on February 1 1968.
Design features of the Duke include turbocharged Lycoming TIO541 engines driving three blade propellers and a 0.32 bars (4.6psi) cabin pressure differential. The airframe was based loosely on the Baron's wing and undercarriage, plus a new fuselage employing bonded honeycomb construction. Optional fuel tanks in the wings were offered, increasing range.
Deliveries of the initial 60 model began in July 1968. Further development led to the improved A60. Appearing in 1970 it introduced an enhanced pressurisation system and longer life yet lighter turbochargers which increased the maximum altitude at which the engine could deliver maximum power, thus improving performance.
The definitive model of the Duke family is the B60. New interior arrangements and more improvements to the turbochargers were the main changes to this model, which first appeared in 1974. Production ceased in 1982.
Since its appearance the Duke has been regarded as something of a hot ship, with its high performance in a relatively small package the main attraction. However, this image did not translate into anything other than modest sales because of the Duke's relatively complex systems (turbochargers and pressurisation among them) and high operating costs.