Abstract: A smooth surfaced, submerged air inlet for use generally forwardly of an engine in an aircraft (missile or other air vehicle). The inlet has an opening having wall surfaces adapted to be flush with or inwardly of an aircraft body surface. The wall surfaces of the opening have a leading and outer end in a plane and the surfaces extend inwardly to form an uncovered shallow channel-shaped portion to the inlet, the channel portion deepening inwardly in the trailing direction and continuing into a partial ellipse portion of the opening. The ellipse portion deepens inwardly as it extends in a trailing direction and has substantially parallel wall surfaces extending outwardly of the ellipse in the direction toward the level of the plane. There are extensions of said substantially parallel wall surfaces diverging outwardly to said plane.