Abstract: Applicant's Side Force Enhancer for use with a slender planar object which hydrodynamically planes proximate to the interface of a liquid and gas environment. The side force enhancement device comprises a plate having an inner surface and outer surface terminating at an upstream leading edge and downstream trailing edge, said plate mounted to the upper surface of said planar object at a predetermined location along the length of said planar object's side edge. The side force enhancing plate's upper most surface is positioned a predetermined distance below the upper surface of said planar object, said plate's lower most surface positioned a predetermined distance below said planar object's lower surface. The inner surface of said plate is proximate to said planar object's side edge, defining an angular relationship therewith. Said plate has a preferred length to height ratio and said angular relationship defines a preferred range of angle.