The utility model provides a high -speed boat variable angle who unites surperficial oar propeller presses unrestrained device, including hydraulic rod, unrestrained board is pressed, motor etc. To the pivot. Press unrestrained board to install in surperficial oar top, be fixed in tail springboard decurrence, and it is adjustable with tail springboard contained angle. The utility model discloses the ripples is prevailed for the surperficial oar of interception to main effect behind splash that the during operation produced and ship, its meaning as follows mainly: promote the stealth ability of motor boat, reduce the mesh that pressure drag reaches the drag reduction, adjustment motor boat gesture promotes motion stability, conveniently back a car. The utility model discloses compact structure, it is with low costs, and the nature controlled is strong, the propulsive high -speed boat of mainly used surface oar.