LearAvia Lear Fan

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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 an innovative 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 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 elevators pointed upward at an angle, similar to those on the V-tail Beechcraft Bonanza, and a stubby rudder 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.

Many years in development, it was not completed before inventor Bill Lear died in 1978. He begged his wife, Moya Lear, to finish it. With the help of investors, she attempted to do so, but the plane never made it into production. The FAA was not concerned about its use of innovative materials; rather, it failed to obtain certification because of concerns that even with two engines, the gear mechanism that powered the single propeller might fail, possibly resulting in a crash.