Although predominant in liquids, cavitation exists to an extent in gas as it has fluid dynamics at high speeds. For example a bullet with a flat tip moves faster underwater as it creates cavitation compared to a bullet with a sharp tip. An ideal shape for aerodynamic cavitation is a dune. It has such a form that provides minimal resistance to the wind. A surface with small dunes installed on aircraft and various high speed vehicles, the total friction against the air will decrease several times. The dune surface pushes the air upwards, underneath and behind the air pressure drops reducing friction. The dune may increase frontal resistance, but it will be compensated by a decrease in the total friction area, as it happens in an underwater bullet. As a result, the speed of the aircraft or vehicle will increase significantly.