| Duke | |
|---|---|
 | |
| General information | |
| Type | Light aircraft |
| Manufacturer | Beechcraft |
| Number built | 596 [1] [2] |
| History | |
| Manufactured | 1968–1983 |
| Introduction date | July 1968 |
| First flight | December 29, 1966 |
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. [3] 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 Electro-mechanical systems, which were highly advanced when the aircraft was introduced, were superseded in other aircraft with simpler I/C controlled mechanical parts.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 380 horsepower (280 kilowatts) each. Other systems, parts, and FAA-certified technicians are increasingly difficult to locate. Normally, pilots figure 45 gallons per hour (170 L/h), plus another 40 US gal (150 L) 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 28 US gal (110 L) and the maximum useful load by 400 lb (180 kg). The take-off length required is shortened by over 1,500 ft (460 m) to only 1,000 ft (300 m) and the landing distance is reduced by over 2,000 ft (610 m) to only 900 ft (270 m). The maximum rate of climb is increased from 1,600 to 4,000 ft/min (500 to 1,200 m/min), reducing the time to climb to 25,000 ft (7,600 m) from 25 to 9 minutes. The cruise speed is increased to 290 knots (540 km/h) at 29,000 ft (8,800 m). The modification does have some disadvantages as it increases fuel burn from 56 to 66 gal/h (210 to 250 L/h) and lowers the certified ceiling from 30,000 to 28,000 ft (9,100 to 8,500 m). [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]
Built to the quality standards of a King Air, the six-place Duke sported 380 hp [280 kW], Lycoming TIO-541 engines – rare beasts, those – which means when both come due for overhaul, the choice is the overhaul or buying a small house in the Midwest. The assertive lines of the airframe made for a startlingly attractive airplane, but led to high costs of manufacture and, surprising to the casual onlooker, horrendous drag. There are those who claim that the Duke was purposefully designed to be about 30 knots [55 km/h] slower than it could easily have been on the available power simply because otherwise it would have been faster than the flagship of the Beech line, the King Air. The roughly 230-knot [430 km/h] maximum cruise speed is only marginally less than that of a King Air 90 and about the same as a Cessna 421, which carries more on slightly less horsepower. While the Duke shares the delightful handling of the Beech line, should pilots have the joy of single-engine operation, they will be up against the highest rudder-force of any piston twin – 150 pounds-force [670 newtons] at Vmc – which happens to be the maximum the FAA allows. Owners report buying a Duke partially because of its looks, but selling it because of the cost of keeping it running. They describe King Air maintenance costs in a piston-twin airframe and recognize that the value of the airplane is entirely dependent on the engines. A gear-up landing means an engine teardown and propeller replacement, along with some sheet metal work. The cost is so high in relation to the value of the airframe that, in many cases, the insurance company will consider the airplane a total loss.
Angola [14] 
Jamaica 
Data from Janes's All The World's Aircraft 1976–77 [16]
General characteristics
Performance
Related development
Media related to Beechcraft Duke at Wikimedia Commons
The Piper PA-23, named Apache and later Aztec, is an American four- to six-seat twin-engined light aircraft aimed at the general aviation market. The United States Navy and military forces in other countries also used it in small numbers. Originally designed as the Twin Stinson in the 1950s by the Stinson Aircraft Company, Piper Aircraft manufactured the Apache and a more powerful version, the Aztec, in the United States from the 1950s to the 1980s.
The Piper PA-24 Comanche is an American single-engine, low-wing, all-metal monoplane of semimonocoque construction with tricycle retractable landing gear and four or six seats. The Comanche was designed and built by Piper Aircraft and first flew on May 24, 1956. Together with the PA-30 and PA-39 Twin Comanches, it made up the core of Piper's lineup until 1972, when the production lines for both aircraft were destroyed in the 1972 Lock Haven flood.
The Piper M-Class is a family of American light aircraft manufactured by Piper Aircraft of Vero Beach, Florida. The aircraft are powered by single engines and have six seats. Twentieth century production of the class was all piston engined, but turboprop versions called the M500, M600 and M700 (Fury) are now also available.
The Aermacchi AL-60 is a light civil utility aircraft of the late 1950s and early 1960s, originally designed by Al Mooney of Lockheed in the United States. After the company decided not to build the aircraft in the US, it was manufactured in small quantities in Mexico, and a few were assembled in Argentina by Aviones Lockheed-Kaiser Argentina. It was also built in quantity under licence by Aermacchi in Italy and Atlas Aircraft Corporation in South Africa.
The Beechcraft Model 50 Twin Bonanza is a small twin-engined aircraft designed by Beechcraft as an executive transport for the business market. It was developed to fill a gap in Beechcraft's product line between the single-engined Model 35 Bonanza and the larger Model 18. The Twin Bonanza is dissimilar to the Bonanza, being much larger and heavier and using more powerful engines, while in its earliest form having only half the passenger capacity of the Model 18.
The Piper PA-38-112 Tomahawk is a two-seat, fixed tricycle gear general aviation airplane, originally designed for flight training, touring and personal use.
The Piper PA-30 Twin Comanche is an American twin-engined cabin monoplane designed and built by Piper Aircraft. It was a twin-engined development of the PA-24 Comanche single-engined aircraft. A variant with counter-rotating propellers was designated the Piper PA-39 Twin Comanche C/R.
The Cessna T303 Crusader is an American six-place light twin-engined aircraft built by Cessna Aircraft Company. Production ceased in 1986.
The Cessna 441 Conquest II is the first turboprop powered aircraft designed by Cessna and was meant to fill the gap between their jets and piston-engined aircraft. It was developed in November 1974, with the first aircraft delivered in September 1977. It is a pressurized, 8–9 passenger turbine development of the Cessna 404 Titan. The ICAO designator as used in flight plans is C441.
The Cessna 425, known as the Corsair and later as the Conquest I, is an eight-seat American pressurized turboprop twin-engined light aircraft. Now out of production, it was built by Cessna Aircraft of Wichita, Kansas, between 1980 and 1986.
The Piper PA-31T Cheyenne is a twin-engine turboprop development of the earlier PA-31P Pressurized Navajo.
The Piper PA-31 Navajo is a family of twin-engined utility aircraft designed and built by Piper Aircraft for small cargo and feeder airlines, and as a corporate aircraft. Production ran from 1967 to 1984. It was license-built in a number of Latin American countries.
The Cessna 421 Golden Eagle is an American six or seven seat twin-engined light transport aircraft, developed in the 1960s by Cessna as a pressurized version of the earlier Cessna 411.
The Cessna 340 is a twin piston engine pressurized business aircraft that was manufactured by Cessna.
The Grob G 120 is a two-seat training and aerobatic low-wing aircraft with a carbon composite airframe, built by Grob Aircraft. It is based on the Grob G 115TA training aircraft and is specially designed for military and civil pilots training. It has a retractable tricycle landing gear and a low tailplane.
The Bellanca Viking and Super Viking are a series of single-engine, four-seat, high performance, retractable gear aircraft manufactured in the USA during the 1960s and 1970s. The aircraft developed through modifications of classic designs by the aviation pioneer Giuseppe Bellanca. A total of 1,356 Vikings have been produced with most production between 1968 and 1975.
The Diamond DA50 is a five seat, single-engine, composite aircraft designed and built by Diamond Aircraft Industries. First shown in 2006, it made its maiden flight on 4 April 2007. The project has been proposed to be powered by several different engines, but was certified on 9 September 2020 with the Continental CD-300 diesel.
The Lancair Evolution is an American pressurized, low wing, four-place, single engine light aircraft, made from carbon fiber composite, developed by Lancair and supplied as an amateur-built kit by Evolution Aircraft.
The Piper Aerostar is an American twin-engined propeller-driven executive or light transport aircraft, designed by Ted R. Smith. It was originally built by Ted Smith Aircraft Company, but the design was acquired in 1978 by the Piper Aircraft Corporation, which continued production of the aircraft as the PA-60.
The Wickham B is an American experimental twin engined, homebuilt aircraft.