Freezes The Materials Choices For The Aircraft
In preparation for the S-LSA American certification, Lisa Airplanes is continuing its series of test runs at both Chambery-Savoy Airport and Bourget Lake. Meanwhile, the French company is completing its industrial process and unveils its technological choices regarding materials.
The French manufacturer which is developing the amphibious skiplane Akoya, has followed up its flight tests from both the airport runway and Bourget Lake with intensive taxiing tests on the lake, which the company says proved the stability of the seafoils and maneuverability of the Akoya at low speed.
"Akoya flows easily upon contact with water at a speed up to 90km/h (49 knots), widening even more Akoya’s capabilities. We’re thrilled with the seafoils performance and with the maneuverability and stability they provide. We’ve broken the seaplane rules but the result of our work is now acknowledged by the most renowned aviation experts," said Jean-François Clavreul, Research and Development Manager.
Test pilot Gérald Ducoin recently completed stall tests in the first production Akoya with several weight and balance configurations and different flap positions, in which the aircraft demonstrated docile characteristcs. Ducoin reported that the Akoya does not have a “nose-down” tendency, which means that at 45 knots, the airplane tends to go down but the nose of the aircraft always stays above the skyline. The airplane keeps its lateral and longitudinal stability; the pilot just needs to push the stick to restore the speed and reverse the stall. This behavior results from four years of experimentation in wind tunnel and in flight that enhanced our design choices related to pilot safety.
Meanwhile, Lisa’s engineers are completing the Akoya’s production preparation. All structural components and materials choices are now frozen. The fuselage, wings and many small parts are made of composite materials: fiberglass, Kevlar, and mostly light-weight sandwich structures made of polymer foam core material and carbon fiber reinforced plastic (CFRP) resin preimpregnated (prepreg) supplied by Umeco. The mechanical parts are made of aluminum and titanium.
All parts are treated against corrosion. The global weight optimization allowed for the design of a 410kg (903 lbs)-empty weight aircraft while featuring an impressive standard equipment and instrumentation package, including an emergency airframe parachute, folding wings, electrically operated canopy, retractable landing gear equipped with skis, and cockpit amenities. (Images provided by Lisa Aircraft)