Design of a natural laminar flow airfoil for light aircraft

A new natural laminar flow (NLF) airfoil, the NALNLF-13; 208, has been designed for a light aircraft. It has been shown that the NAL-NLF-208 airfoil performs better than the Wortmann FX-60-177 airfoil because it is thicker and is estimated to give better aerodynamic performance larger L/ D) in the operating CL range. To take account of the difficulties in fabrication, the NALNLF-208 airfoil has been modified to incorporate appropriate bluntness at the trailing edge. A surface waviness (amplitude of 0.025070and wavelength of 4.1 %, each of the local chord) superimposed on the blunted airfoil is shown to have no significant 13; effect. It is concluded that the NAL-NLF-208 is robust with respect to performance and fabrication and could replace the Wortmann airfoil as a candidate for light aircraft after13; testing.