The boundary layer is the thin region of fluid pulled along by a vehicle as it moves through a stationary fluid (or as moving flow passes a stationary wall).
With increasing environmental awareness and regulation in conjunction with high fuel costs, energy conservation in the aviation industry is a prevalent issue. Meeting this challenge will translate into financial benefits for manufacturers and passengers. It is also toward our social responsibility of energy conservation, emission reduction, and environmental protection. Aerodynamic drag reduction will reduce thrust demands, and consequently, both emissions and fuel consumption. For commercial aircraft, at cruise conditions over half of the aerodynamic drag on civilian aircraft is attributed to skin-friction, which is due to the presence of the boundary layer.