A jet boat includes a hull, a jet propulsion nozzle mounted to a rear of the hull, and an articulating keel attached at the rear of the hull. The articulating keel is connected to the jet propulsion nozzle via a connecting portion such that when the jet propulsion nozzle is turned, at least a portion of the articulating keel is turned with the jet propulsion nozzle. The jet propulsion nozzle turns about a first pivot axis extending vertically or substantially vertically, and the articulating keel turns about a second pivot axis extending vertically or substantially vertically. The first pivot axis of the jet propulsion nozzle is coaxial with the second pivot axis of the articulating keel.

A system for controlling a marine vessel having first and second waterjets, corresponding first and second steering nozzles and corresponding first and second reversing buckets. The system comprises a speed control device for providing a first vessel control signal that corresponds to a speed to be provided to the marine vessel, a processor configured to receive the first vessel control signal and that is configured to provide at least one first actuator control signal coupled to the first and second waterjets, and at least one second actuator control signal coupled to the first and second steering nozzles and the first and second reversing buckets. The system any of improves upon turns provided by conventional waterjet propulsion systems, improves upon slowing down or stopping marine vessels as is done by conventional waterjet propulsion systems, and improves upon the controllability of the waterjet propulsed marine vessel at low vessel speeds.

A system for controlling a marine vessel having first and second waterjets, corresponding first and second steering nozzles and corresponding first and second reversing buckets. The system comprises a speed control device for providing a first vessel control signal that corresponds to a speed to be provided to the marine vessel, a processor configured to receive the first vessel control signal and that is configured to provide at least one first actuator control signal coupled to the first and second waterjets, and at least one second actuator control signal coupled to the first and second steering nozzles and the first and second reversing buckets. The system any of improves upon turns provided by conventional waterjet propulsion systems, improves upon slowing down or stopping marine vessels as is done by conventional waterjet propulsion systems, and improves upon the controllability of the waterjet propulsed marine vessel at low vessel speeds.

A water jet propulsion boat includes a boat body including a keel, and a cavity in a front portion of the keel extending in a left-right direction of the boat body.

A water jet propulsion boat includes a boat body including a keel, and a cavity in a front portion of the keel extending in a left-right direction of the boat body.