LearAvia Lear Fan
Lear Fan 2100 | |
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Two Lear Fans during a 1982 display flight | |
Role | Business aircraft |
National origin | United States of America |
Manufacturer | LearAvia |
Designer | Bill Lear |
First flight | 1 January 1981 |
Number built | 3 |
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The LearAvia Lear Fan 2100 turboprop was made of lightweight composite materials instead of the more usual aluminum alloy. It also featured a pusher design, in which two aircraft engines powered a single constant-speed three- or four-bladed propeller at the rear of the aircraft. A purpose-built gearbox allowed either one or both Pratt & Whitney of Canada PT6B free-shaft turbines to supply power via two driveshafts. The intent of the design was to provide the safety of multi-engine reliability, combined with single-engine handling in case of failure of one of the engines.
Another interesting feature was the Y-shaped empennage at the tail. Two stabilizers pointed upward at an angle, similar to those on the V-tail Beechcraft Bonanza, and a stubby vertical stabilizer pointed downward. However, unlike the V-tail on the Bonanza, there was no pitch/yaw control mixing on the Lear Fan. The downward-pointing rudder also served to protect the propeller from ground strikes during takeoff and landing.
The aircraft had a pressurized cabin and was designed for a service ceiling of 41,000 ft (12 500 m). It could accommodate two pilots and seven passengers, or one pilot and eight passengers.
Design and development
Many years in development, it was not completed before inventor Bill Lear died in 1978. He begged his wife, Moya Lear, to finish it. It was planned for production to be carried out in Belfast Northern Ireland, in a new factory built with money from the British Government in an effort to boost employment.[1][2] After the cancellation of a planned test flight on December 31, 1980 due to technical issues, the first prototype made its maiden flight on January 1, 1981,[3] (officially recorded by sympathetic British government officials as "December 32, 1980" in order to secure funding that expired at the end of that year[4]).
The Lear Fan, however, did not enter production. The US Federal Aviation Administration was not concerned about its use of innovative materials but did not issue the prototype with an airworthiness certificate because of concerns that, despite two engines, the combining-gearbox that drove the single propeller was not adequately reliable. Gearbox wear was found to be unacceptably high. Development was abandoned in 1985.[2]
Survivors
There are Lear Fan aircraft on display at the Museum of Flight in Seattle, Washington,[4] the Frontiers of Flight Museum in Dallas, Texas.[5] and at the Civil Aerospace Medical Institute in Oklahoma City, Oklahoma Civil Aerospace Medical Institute
Specifications
Data from Jane's All The World's Aircraft 1982-83[3]
General characteristics
- Crew: Two
- Capacity: Six passengers
- Length: 40 ft 7 in (12.37 m)
- Wingspan: 39 ft 4 in (11.99 m)
- Height: 12 ft 2 in (3.71 m)
- Wing area: 162.9 sq ft (15.13 m²)
- Aspect ratio: 9.5
- Empty weight: 4,100 lb (1,860 kg)
- Max. takeoff weight: 7,350 lb (3,334 kg)
- Powerplant: 2 × Pratt & Whitney (Canada) PT6B-35F turboprop, 650 shp (485 kW) each
Performance
- Maximum speed: 425 mph (369 knots, 684 km/h) at 25,000 ft (6,100 m)
- Cruise speed: 322 mph (280 knots, 519 km/h) at 40,000 ft (12,190 m) econ cruise
- Stall speed: 88 mph (76 knots, 141 km/h) flaps down, power off
- Range: 1,783 mi (1,548 nmi, 2,869 km)
- Service ceiling: 41,000 ft (12,500 m)
- Rate of climb: 3,450 ft/min (17.5 m/s)
See also
- Aircraft of comparable role, configuration and era
References
- Notes
- ↑ McCellan 2006.
- 1 2 Lear Fan Collapses. Flight International 8 June 1985, p.30.
- 1 2 Taylor 1982, pp. 399–400.
- 1 2 Lear Fan 2100 (Futura). The Museum of Flight. 2009. Retrieved 27 November 2009.
- ↑ Aircraft at the Frontiers of Flight Museum - Dallas, Texas. Frontiers of Flight Museum. Retrieved 27 November 2009.
- Bibliography
- "Lear Fan Collapses". Flight International, 8 June 1985. Sutton, UK:Business Press International. p. 30.
- McClellan, J. Mac. "Flashback to 1981:A Look Back at the Lear Fan". Flying, June 2006. Retrieved 21 November 2009.
- Taylor, John W.R. Jane's All The World's Aircraft 1982-83. London:Jane's Yearbooks, 1982. ISBN 0-7106-0748-2.
- Whitaker, Richard. "Lear Fan: the plastic aeroplane arrives". Flight International, 26 December 1981, pp. 1896–1901.
External links
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