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).

Rule 12 of the collision regulations deals with two sailing vessels approaching each other so as to involve risk of collision. The first part of it is the best known rule in sailing: when they have the wind on different sides, the vessel with the wind on her port side keeps out of the way of the other.

A boat is on port tack when the wind is coming over her port (left) side, so her mainsail and boom are out to starboard. She is on starboard tack when the wind is coming over her starboard side and the boom is out to port. A quick check: if the boom is on your port side, you are on starboard tack and you are the stand-on boat.

When the wind is from directly astern, the rules take the windward side to be the side opposite the one on which the mainsail is carried. So a boat running with her boom out to port is on starboard tack.

If you are on port tack, the usual ways to keep clear are:

• bear away early and pass behind the starboard-tack boat;
• tack early, so that you are on starboard too and sailing alongside rather than crossing;
• if you are clearly far enough ahead, hold on and cross, but only if there is no doubt.

If you are on port tack and see a boat to windward but cannot tell which tack she is on (her mainsail can be hard to see), Rule 12 says you must assume you have to keep clear.

If you are on starboard tack, hold your course and speed so the other boat can predict you, but keep watching. If she is not keeping clear, you must act to avoid a collision. In racing, sailors call "Starboard" to warn a port-tack boat; outside a race it is just as useful to make sure the other crew has seen you.

More in the book: Chapter 13, The rules of the road