Patent ID: 8142241

Claim:
A water jet propulsion watercraft comprising: a hull; an engine disposed inside the hull; a jet propulsion device arranged to be driven by a driving force of the engine, and to jet water rearward from a jet port to thereby apply a propulsive force to the hull; a water detection unit including a water detection chamber arranged such that water around the hull is introduced when the hull is immersed in water, and a water level sensor arranged to detect a water level inside the water detection chamber so as to detect whether or not the hull is immersed in water; a water channel branching from the jet propulsion device, and arranged to introduce water pressurized by the jet propulsion device into the engine; a water introduction channel coupled to the water channel and arranged to introduce the water from the water channel into the water detection chamber; and a control unit arranged to judge whether or not the hull is in water based on an output signal of the water level sensor, to set a maximum rotational speed of the engine to a first rotational speed, and to restrict the rotational speed of the engine to not more than the maximum rotational speed when the hull is not in water.