Going sideways (January 2006)
It’s no secret that bow thrusters are a big help when you’re maneuvering in close quarters, which is why they are becoming common on boats in the 40-foot range. One reason for this popularity is that the units themselves have gotten better. But it’s also true that freeboards are getting higher and many of us either are getting older or are sailing with fewer crew. My 47-footer came with a bow thruster, and I quickly learned to appreciate it. It’s simple to use: hit the button and the bow goes right, hit the button and the bow goes left.
But I soon discovered another level of use. Everyone knows that a thruster moves the bow when the boat is stopped. And everyone knows that you use a thruster to hold or move the bow to port or starboard against the wind. But not everyone knows that the thruster can be used to make the boat go sideways. Here’s how it works.
Let’s say you’re in a marina and the wind is blowing from your port side, pushing you into the dock, and you want to get away from the dock without damaging the starboard side of the boat.
After you’ve gotten the dock lines on board, you might think about pushing the thruster button to push the bow to port, away from the dock. The problem is that only the front half of the boat will be clear. The twisting motion caused by the keel—as the bow goes to port, the stern goes to starboard—will start to press the stern firmly against the dock (A).
There is another way. First turn the helm hard to starboard (toward the dock) and accelerate forward under power. Simultaneously, push the bow thruster button to port, which will push the bow to port and away from the dock. This may seem counterintuitive, but it works. As you turn the helm to starboard, the leading edge of the rudder is pointing to port. The prop wash against the rudder along with the forward motion will move the stern to port and away from the dock (B), while the thruster’s push to port keeps the bow from swinging to starboard and into the dock. As the boat starts to move forward, it will also be moving sideways to port and clear of the dock. Obviously, you need to practice this maneuver to learn exactly how your boat will react.
If you’re turning and the stern is about to bump into something, you can quickly check that motion by using the thruster to move the bow in the same direction the stern is moving. You are, in effect, getting the boat to move sideways even as it is moving forward. When you get these procedures and their timing down correctly, you’ll add a whole new dimension to using your bow thruster to help you maneuver confidently in close quarters. Robert V. Lally
Who has the right of way? (January 2006)
A useful aide-memoire for crossing another vessel in daylight when both boats are under power—in a harbor, for example—is to ask yourself which sidelight you would be seeing if it were dark. If the answer is a red, or port, running light, you must take care and stay out of the other boat’s way. A green light would indicate that you are clear to go. So if you would see a green, or starboard, running light, you can continue carefully on your present course. Tom Cunliffe
Click here to return to the Cruising Tips Archive
