| 摘要 |
PROBLEM TO BE SOLVED: To provide a jet propulsion type planing boat that implements an off throttle steering mode control for steering preferable for a speed at a time of starting the control while restraining a increase in weight, and provide an optimal ship speed detecting apparatus therefor. SOLUTION: The jet propulsion type planing boat jets water from a rear jetting port 21K to pressurize and accelerate the water by a water jet pump P and propels by the reaction of the water. When carrying out the steering and an off operation of a throttle, a throttle opening detecting sensor Sb and a steering position detecting sensor Sp detects the off operation of the throttle and the steering, respectively, and a speed of an engine E is temporally increased to maintain steering function at the time of the off operation of the throttle. The speed detecting apparatus detects a speed of the boat, and the off throttle steering mode control is gradually executed from a high speed area to a low speed area depending on the detected speed of the boat. |
