Who gives way to who at sea?

Even seasoned sailors sometimes get this wrong and in a crowded harbour this can easily lead to a collision or at best considerable embarrassment for a boat that mistakenly thinks it has right of way over another.

I recently went sailing with friends over a busy weekend on the South Coast of England. The conditions were perfect for sailing, a Force 4 breeze, full sunshine and everyone was out to enjoy themselves. While the conditions were perfect, Chichester Harbour was crowded with dinghy sailing races, keelboats, yachts, kayakers, paddle boarders, fishing vessels and countless motor boats of all sizes.

As we sailed towards the harbour entrance the crowding intensified and we kept a constant lookout in all directions. With a full genoa set, it was easy enough to keep a lookout to windward, but to leeward there is a significant blind spot for the person on the helm, so we decided to have a crew member at the bow to keep an all round lookout.

There was quite a bit of discussion about which vessels had right of way over others, so this has prompted me to produce a basic reminder of the give way hierarchy between sailing boats and power boats, plus explanations of what is meant by the give-way vessel, stand-on vessel and the overtaking rule.

The give-way hierarchy

• Power boat gives way to sailing boat.
• Sailing boat gives way to boat engaged in fishing.
• Boat engaged in fishing gives way to vessel with restricted ability to manoeuvre.
• Vessel with restricted ability to manoeuvre gives way to vessel not under command.
• Note: A sailing boat which is motor sailing does not have priority over a power boat, even if it has sails hoisted. 

Sailing boat hierarchy

• Port tack gives way to starboard tack.
• If on the same tack, the windward boat gives way.
• If it is unclear to a sailing boat on port tack which tack another sailing boat to windward is on, then the boat on port tack must give way.

Power boat hierarchy

• If two power boats are heading towards each other, both boats should alter course to starboard, so their port sides will pass each other.
• If two power boats are crossing paths and there is a risk of collision, then the vessel which has the other on its starboard side must give way. It must also avoid crossing ahead of the stand-on boat.
• If a power boat meets another head on and is not quite sure if a collision is likely, then it should assume it does and alter course to starboard.

Give-way vessel

• When two similar vessels are crossing, the one that has the other to its starboard side is the give-way vessel.
• The ‘give-way’ boat is responsible for keeping clear and altering course where necessary to avoid a collision.
• The give-way boat should make an obvious course direction in plenty of time, so the stand-on vessel is in no doubt it has taken avoiding action.

Stand-on vessel

• If you are the stand-on boat, keep to your course and speed to make it easier for the give-way boat to manoeuvre out of your way.
• If the give-way vessel does not take avoiding action, the stand-on vessel must be ready to turn quickly out of the way or stop as a last resort.

Overtaking

• All vessels, whatever their size and type, must keep well clear of others when overtaking.
• It is courteous to overtake a sailing boat on their leeward side, so as not to take their wind.
• The vessel being overtaken must maintain its course and speed.
• The overtaking vessel must be well clear of the other before it can resume its original course, allowing the overtaken vessel to maintain its course throughout the manoeuvre.

A vessel is said to be overtaking another if it is approaching more than 22.5º behind the other vessel’s beam. This overtaking sector covers an arc of 135º, which is the same as the arc of a stern light. At night, it is easy to tell if you are overtaking a vessel because you can see its stern light as you approach it.

During the day, it is not always as easy to be sure you are in the overtaking sector. Are you overtaking or alternatively are you crossing the other vessel’s path, in which case you could have right of way? If in doubt, it is always best to proceed with caution and keep well clear of the other vessel.

Summary

• Keep a lookout at all times.
• Remember to follow the give-way hierarchy. Vessels with priority over you have the right of way.
• When altering course, make sure that the new course does not result in another close-quarters situation.
• Be prepared to reduce speed if you are the give-way boat.

Finally, in a very crowded harbour situation it is wise for sailing boats with engines to furl their sails and proceed under engine until they are clear of the harbour entrance. This is not a rule as such in most harbours but it makes sense and is what we decided to do until we had left the harbour.