Bow thruster 2/14

 

A ship equipped with a bow thruster, the indicating symbol is visible below the R of MARIE

 

A vessel equipped with a bow thruster, the indicating symbol is visible below the R of MARIE

 

 

A bow thruster, also known as a tunnel thruster, is a thruster built into the bow of a vessel to enhance its maneuverability. Usually, a bow thruster is just a tunnel below the waterline through the bow. An impeller in the tunnel can create thrust to both ways which makes the vessel turn.

Ships equipped with bow thrusters have a sign above the waterline over each thruster on both sides. This sign symbolizes the thruster with a big white cross in a white circle.

Bow thrusters make docking a ship easier, since they can turn the ship even if it's not moving and in some cases allow a ship to dock without the otherwise required assistance of tugboats, saving the costs of such service.

 

Stern thrusters

 

 

All crafts from 23 to 100 feet can utilize Stern Thrusters. For boats up to 40 feet, a single thruster will generate 6 hp (or 118 pounds of thrust). For boats between 41 and 100 feet, twin mounts (shown above) are required and will achieve 12 hp.

Single screws handle like a twin screw and twin screws yield dramatic improvement in maneuverability.