With a crop of very light jets (VLJs) in development it's interesting to look back at another would be revolution in airplane design, the Lear Fan. In the late 1970s inventor and promoter Bill Lear conceived a turboprop airplane that would have twin engines driving a single propeller mounted on the tail. The airplane was made entirely from carbon graphite material which was expected to give it an unprecedented light empty weight. Maximum cruise speed was projected to be 350 knots, faster than Cessna's new Mustang light jet.
The Lear Fan garnered a pot full of orders, several prototypes flew many hours in flight test, but in the end unsolvable problems with the gearbox that combined the output of the two turbine engines, and other issues with weight and aerodynamics, doomed the project. One difference between the Lear Fan and some of today's proposed small jets is the price which was $1.6 million in 1981. That was a lot of money, but then the Lear Fan promised to do things never before possible. This story was written not long after the first prototype Lear Fan flew. FLYING 1981 Article: AIRCRAFT DESIGN: LEAR FAN BITES INTO THE BUSINESS FLEET By J. Mac McClellan
AVIATION'S NEWEST AIRPLANE is reaching out to stir up our oldest feelings. The Lear Fan 2100 has rekindled emotions not generated by big companies with engineering groups carrying out the direction of large corporate management staffs. The Lear Fan takes us back to the days when individuals put their names on airplanes and then went out to see how well they would fly and if anyone would buy them.
LearAvia headquarters in Reno, Nevada is filled with pictures of and sayings by the late William P. Lear, the inventordesigner-promoter who shaped the Lear Fan. A favorite saying, and one that best describes the Lear Fan program is, "Don't take a nibble, take the big bite." That is exactly what the people at Lear Fan have done.
The "big bite" is an attempt to build the first commercially successful twin-engine, singleprop pusher airplane, and if that isn't challenge enough, the airplane will be built entirely from composite materials. Either the pusher design or the nonmetal structure would be enough to label the Lear Fan as revolutionary; together they can only be called radical.
Lear's wife, Moya, has directed the Lear Fan project since her husband's death in 1978. Among his final instructions, it is reported, he told her, "Finish it, Mommy, finish it." Customers have plunked down hard cash to reserve 180 delivery spots and the prototype is flying. The British Government has supplied $50 million in loans and grants to assure production of the Lear Fan in Northern Ireland. All told, $100 million is committed to the project, which puts it in the big leagues. But the Lear Fan, both by design and circumstance, will always be credited to one man.
Bill Lear first advocated a twin-engine, single-propeller pusher airplane in a story in nowdefunct Skyways Magazine in 1954. Lear contended that such a design would, because of reduced weight and drag, perform better and more safely, without the possibility of asymmetric thrust if an engine failed.
Lear kept his pusher design concept on the back burner as he presided over advances in avionics, car radios and the first business jet. During the 1970s, he directed his aviation design talents to a new business jet he called the Learstar 600. By 1977, Canadair had purchased the production rights to the airplane; it enlarged the cabin and began production of the airplane, now called the Challenger.
With the Learstar gone to Canada, Lear decided the time was right for his pusher. Applying his "big bite" theory, he concluded that the airplane could be transformed from revolutionary to spectacular through use of lightweight composite materials that were now being used for parts of various aircraft. The Lear Fan 2100 began to take shape in the inventor's mind and on paper.