| Duke | |
| First Flight: | December 29, 1966 |
| Introduction: | July 1968 |
| Produced: | 1968–1983 |
| Number Built: | 596[1] [2] |
The Beechcraft 60 Duke is an American-built twin-engine, piston-driven fixed-wing aircraft designed and produced by Beechcraft. The aircraft has retractable tricycle landing gear and a pressurized cabin. The engines are turbocharged, which also pressurize the cabin with bleed air.
Development of the Beechcraft 60 began in early 1965, which was designed to fill the gap between the Beechcraft Baron and the Beechcraft Queen Air. On December 29, 1966, the prototype made its first flight. On February 1, 1968, the FAA issued the type certificate.[3] [4] Distribution to customers began in July 1968. The passenger cabin is fitted with club seating and entry is by means of a port-side airstair entry door in the rear fuselage.[5]
The Beechcraft A60, which came onto the market in 1970, represented an advancement over the Baron, with an improved pressurized cabin utilizing advanced bonded honeycomb construction, lighter and more efficient turbochargers, and improved elevators. The last variant, the B60, was introduced in 1974. The interior arrangement was renewed and the engine efficiency again increased by improved turbochargers.[6] The Beechcraft 60 was, despite its very good performance, only a moderate seller, principally because the complicated technology demanded a high expenditure on maintenance. Production was stopped in 1983.[1]
Most of the Duke B-60s still flying have retained their original equipment. Electro-mechanical systems, which were highly advanced when the aircraft was introduced, were superseded in other aircraft with simpler I/C controlled mechanical parts. The aircraft design uses turbocharged Lycoming TIO541-B4 engines that develop 380hp each. Other systems, parts, and FAA-certified technicians are increasingly difficult to locate. Normally, pilots figure 45USgal/h, plus another 40USgal for each takeoff and climb as typical fuel consumption for cross-country planning. Owners compare the Beechcraft B60 to classic sports cars—noting that they do not fly Dukes to economize.[7]
Some Dukes have been modified by Rocket Engineering of Spokane, Washington, replacing the Lycoming piston engines with Pratt & Whitney Canada PT6A-21 or -35 turboprops. Called the Royal Turbine Duke conversion,[8] the modification increases fuel capacity by 28USgal and the maximum useful load by 400lb. The take-off length required is shortened by over 1500feet to only 1000feet and the landing distance is reduced by over 2000feet to only 900feet. The maximum rate of climb is increased from 1600to, reducing the time to climb to 25000feet from 25 to 9 minutes. The cruise speed is increased to 290kn at 29000feet. The modification does have some disadvantages as it increases fuel burn from 56to and lowers the certified ceiling from 30000to.[9] [10] The supplemental type certificate was issued on May 12, 2006.[11]
The Duke was purchased by corporate and private pilot owners. Most were registered in the United States but examples were exported to many countries including Argentina, Australia, Brazil, Canada, Croatia, Finland, France, Germany, Honduras, Iceland, Serbia, Slovenia, Sweden, Switzerland, South Africa and the United Kingdom. One Duke was flown by the Jamaica Defense Force. Many remain in service in the early twenty-first century.
In reviewing the aircraft in 2008, Rick Durden of AVweb stated,[12]