Pilot Journal
Tuesday, April 7, 2009

Lancair Evolution: Revolutionary Homebuilt

Lancair reaches for new horizons in four-place homebuilts with the Evolution propjet

Clean-Sheet Design
Contrary to what you might imagine, the Evolution has very little mechanical similarity to Lancairs of old, though it’s true that several of the company’s previous homebuilt airplanes have been converted to turboprop power. There is some slight family resemblance to the other four-seat Lancairs—swept fuselage, waspish empennage—but it’s purely coincidental. Lance Neibauer, father of the original Lancairs, had no input on the new airplane.

The Evolution is pretty much a clean-sheet design, specifically configured for pressurized, high-altitude flight and turbine power. It’s a product of 21st-century CAD/CAM (computer-aided design and manufacturing) technology, plus modern safety features such as a BRS parachute, AmSafe seat belts and 26-G-energy- absorbing seats.

lancairRocket Engineering AirBoom Cannula
The AirBoom Cannula headset accessory dispenses with bulky masks and offers oxygen delivery to 18,000 feet. The moist-air/oxygen blend eliminates dry nose while conserving oxygen.

Bill Cox and Tim Ong fly the Lancair Evolution in formation with Bob Jeffery and Ernie Sutter in their Lancair Legacy race planes.
In fact, Lancair went the extra mile to design and build the Evolution to comply with FAA Part 23 production aircraft standards. The Lancair IVP, the company’s previous flagship design, was a brilliantly executed airplane, but, perhaps incredibly, it’s now nearly 20 years old. It was designed with a small wing configured for a maximum 3,550 pounds. With only 108 square feet of area (including winglets) to support the weight, wing loading on the IVP was a high 32.9 pounds per square foot. That’s a fairly stout wing loading that helps generate a smooth ride in turbulence, but also can precipitate a fairly abrupt stall.

The goals of the Lancair Evolution were to upgrade performance while matching airframe and powerplant to the wing and guaranteeing a relatively benign stall. To that end, the new airplane sports more span and a longer chord to generate about 35 square feet more wing area. Aspect ratio increases from 9.0 on the IVP to 10.3 on the Evolution. All other factors being equal, a higher-aspect-ratio wing contributes to better climb and glide and improved high-altitude performance.

Additionally, the Evolution incorporates a new airfoil that’s totally divergent from the wing on the IVP. It’s a proprietary section designed to help tame the stall while preserving high-cruise capability. As with all previous Lancairs, the airplane’s composite construction results in a beautifully smooth and consistent wing and fuselage surface, with no rivet heads or section lines to reach out and grab the wind. If there was ever an airplane that reduced parasite drag to the absolute minimum, this is it.

Labels: Turboprops


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