How to Maneuver a Twin Engine Boat With a Bow Thruster

Maneuvering is the use of your boat's bow thruster and twin engines to turn your boat around in its own length or parallel park in tight spaces by "walking" your boat sideways. While you must remain mindful of the effects of the wind and sea, you'll enjoy a new level of control. The key to dealing with a bow thruster, like other control and power systems aboard a boat, is to trust that it will do what it should.

Instructions

Parallel Parking

1. Start the bow thruster before you begin to move into position. This allows you time to evaluate the situation should the bow thruster prove inoperative.

2. Pull your boat parallel to the dock space you will occupy and stop the boat. Move your throttles into reverse if necessary to "take all way off" the boat, moving them to neutral as soon as you are stopped. Ensure that you have sufficient room forward and aft in the dock space.

3. Take note, while the vessel is at a standstill, of the direction of the wind and current, and their effect on your vessel, blowing it forward or aft, or to or away from the dock space.

4. Turn the wheel to the left if the dock is on your starboard side. Move both main engine throttles to forward, at idle. When the stern begins to move toward the dock, move the bow thruster handle, mounted perpendicular to the centerline of the boat, toward the dock, also at idle. The bow will begin to move toward the dock as well.

5. Use slight changes in the speed of one or both of the main engine throttles to move the boat backward or forward, only as much as necessary, controlling the motion of the boat forward and backward in relation to the dock space as the boat moves toward the dock. Use slight changes of the bow thruster's speed to increase or decrease the speed with which the bow moves toward the dock.

6. Allow the main engines and the bow thruster to remain in operation when the boat touches the dock and until the boat is secured to the dock. When the vessel is secure, move all throttles to the neutral position. Turn off the bow thruster and secure the main engines.

Turning About in One Boat Length

1. Start the bow thruster and the main engines, if the mains are not operating. Decide whether the turn is to the left or right.

2. Turn the wheel "hard over"--as far as you can--in the direction you wish to turn. If you are turning left, for example, turn the wheel hard over to the left and engage the port engine--the main on the inside of the circle you will make in the water--into reverse, while engaging the starboard engine--the main on the outside of the circle--into forward gear. Push the bow thruster handle to the left.

3. Watch your compass heading if in the open sea, or landmarks if in harbor, to gauge the progress of your turn. Increase the speed of your mains slightly and, after that slight increase, use the bow thruster throttle handle alone to control the rate of your turn--how fast you move.

4. Move the bow thruster handle to neutral (straight up) as you reach your desired course or orientation. Shift the mains to neutral.

Tips & Warnings

• Don't speed through these evolutions. There is no "Fast Driving Award" given for parking a boat in record time. Beyond that, remember that going fast does nothing except get you into trouble faster.

References

• "Chapman Piloting, Seamanship and Small Boat Handling"; E. Maloney; 1996