Abstract: The improved helicopter anti-icing and deicing system and method includes mounting an airfoil shaped manifold transversely of the helicopter and filling the manifold with anti-icing or deicing fluid which is not under sufficient pressure to spray outwardly from the manifold. Instead, the rear edge of the manifold is provided with small, spaced openings which cause fluid droplets to form along the rear edge of the manifold and to then drop downwardly by gravity. The helicopter is positioned above a power line with the power line extending in the direction of the helicopter longitudinal axis and droplets are caused to exit the manifold as the helicopter flies along the power line.