A stop member (74; 174) is affixed to an elongated rudder blade (16) near its top and projects forward beyond the leading edge of the blade. A frame (62) in which the blade (16) is slidable lengthwise extends along a portion of the trailing edge of the blade and forward along the opposite sides. A separate mounting block (12) has a groove (48) receiving a portion of the leading edge of the blade (16). A pivot component (82) is mounted in the groove (48) for engagement against the underside (78) of the stop (74) when the blade (16) is in a normal upright steering position. A spring (52) is connected between the mounting block (12) and the frame (62) to bias the frame toward a position in which the blade (16) received therein extends in an upright steering position. From such position, the blade (16) can be swung upward and rearward, followed by forward translational movement through the frame (62) and along the mounting member (12).