Flight Evaluation of an Insect Contamination Protection System for Laminar Flow Wings

The ability of modern airplane surfaces to achieve laminar flow has been well-accepted in recent years. Obtaining the maximum benefit of laminar flow for aircraft drag reduction requires maintaining minimum leading-edge contamination. Previously proposed insect contamination prevention methods have proved impractical due to cost, weight, or inconvenience. Past work has shown that insects will not adhere to water-wetted surfaces, but large volumes of water required for protection rendered such a system impractical. This paper presents results of a flight experiment conducted by NASA to evaluate the performance of a porous leading-edge fluid discharge ice protection system operated as an insect contamination protection system. In addition, these flights explored the environmental and atmospheric conditions most suitable for insect accumulation. These tests have shown that the protection of laminar flow wings against insect debris contamination appears feasible with very small volumes of fluid, thus offering an attractive alternative to the insect protection systems previously proposed.