Textbook of Sailing

Rules of the road

Who gives way to whom on the water under the collision regulations (COLREGs), how to keep clear of ships, and what navigation lights and sound signals mean.

Does a sailboat have right of way over a powerboat?

Usually, yes: under COLREGs Rule 18 a power-driven vessel keeps out of the way of a sailing vessel. The main exceptions are when the sailing boat is overtaking, or when she would impede a ship in a narrow channel.

Is a sailboat with its engine running a power-driven vessel?

Yes. Under the COLREGs a sailing vessel is one under sail with any engine not being used, so as soon as the engine is driving the boat she counts as a power-driven vessel, even with the sails up.

Which sailing boat gives way, port tack or starboard tack?

The boat on port tack gives way. When two sailing boats meet on opposite tacks, the one with the wind coming over her port side keeps out of the way of the one with the wind on her starboard side (COLREGs Rule 12).

What is the windward boat rule in sailing?

When two sailing boats are on the same tack, the boat to windward keeps out of the way of the boat to leeward (COLREGs Rule 12). The leeward boat is the one further downwind, and is often less able to get out of the way.

Who gives way when one boat overtakes another?

The overtaking boat always keeps out of the way of the boat being overtaken (COLREGs Rule 13). This applies to every vessel, sail or power, and it overrides the usual sail-before-power order.

What is a give-way vessel and a stand-on vessel?

The give-way vessel is the one the rules require to keep out of the way; the stand-on vessel is the one that must hold her course and speed. Both still have a duty to avoid a collision (COLREGs Rules 16 and 17).

How do you tell if you are on a collision course with another boat?

Watch the other vessel's bearing. If it stays the same while the distance between you closes, there is a risk of collision. If it moves steadily ahead or astern, she will pass ahead of you or behind you.

Do sailing boats have to give way to ships in a channel?

Yes, in effect. COLREGs Rule 9 says a sailing vessel, or any vessel under 20 metres, must not impede a vessel that can navigate safely only within a narrow channel. Keep out of a ship's way, and do it early.

What navigation lights does a sailboat need?

Under sail, a red sidelight to port, a green sidelight to starboard and a white stern light (COLREGs Rule 25). Under engine you add a white masthead light shining forward, and at anchor you show an all-round white light.

What do horn signals mean on a boat?

One short blast means I am turning to starboard, two short blasts I am turning to port, three short blasts I am going astern, and five or more short blasts mean I doubt your intentions (COLREGs Rule 34). Fog has its own signals.