What is a Tri-Sail and How to Use One.

A tri-sail is not something many day sailors are ever likely to see or use. However, if you have one it’s important that you know what it’s for, where it’s kept and how and when you should rig it for best affect.


If you ever compete in one of the iconic offshore sailing events such as the Fastnet Race or the Sydney Hobart Race then you will be required to rig your storm sail and tri-sail and parade past the committee vessel so that they can be inspected. That is how important the ability to rig a storm jib and tri-sail is considered by the authorities.

Why is a tri-sail used?

A tri-sail is used in heavy weather (as is a storm jib) and it is primarily used as a replacement to the mainsail, thus balancing the storm jib and offering some balance to the small headsail and an ability to maintain height on the wind, even in a severe gale or storm and thus save you from a lee shore.

Removing the boom from the equation allows for safer boat handling, including gybes in heavy winds and seas and still allows the vessel to heave-to if deemed necessary. 

How is a tri-sail rigged?

Tri-sails are made of a durable, heavyweight material, very much like a storm jib. They are usually bright orange or have orange or reflective material on them and they’re relatively small in area - after all, they are designed to be used in heavy weather.

The tri-sail has its luff in a track on the mast (either the mainsail track or its own separate track alongside) and its tack is attached to the gooseneck on the boom, usually by way of a strop that is attached to its tack. This allows you to set a reduced sail area higher than usual, thus keeping your sails clear of that heavy green water that might be crossing your coach roof in the middle of a storm. The weight of which might otherwise damage or destroy your mainsail or damage your rig.

The clew then has two sheets attached to it (very much like a headsail) and these are normally run down to the deck, one on either side of the yacht, through blocks near the quarters and then onto spare winches. 

The idea is that the main sail is lashed hard to the boom and the boom is then lashed securely to the deck, perhaps resting the boom end on a fender or coiled line to reduce potential for damage of the traveller. This securing of the boom reduces the dangers inherent in a heavy, dynamic spar thrashing around in heavy winds and has the potential added benefit of lowering the weight of the mainsail - and thus the centre of gravity and probably also improving righting moment and ability in the event of a knockdown or inversion.

The Pros and Cons of a Tri-sail

The most important thing to bear in mind when considering rigging storm sails, especially the tri-sail, is timing. Set your sails too soon and you may find yourself underpowered in a building seaway, not a pleasant experience! At the same time, going about the rigging of your storm sails in the middle of a severe gale is not to be advised. The foredeck is an inhospitable place in a big sea and trying to rig a new headsail (or worse still, drop a mainsail, secure it and set a tri-sail) is very challenging.

The most seaworthy blue water vessels will have a separate inner stay allowing you to rig the storm jib on the inner stay early-on before the primary headsail is dropped or furled away and secured. In the same theme, a separate tri-sail mast track is a real bonus as it means you don’t need to drop the mainsail prematurely but it does allow you to pre-rig the tri-sail and have it ready for action. Also, with two tracks, you won’t need to remove some or all of the yacht’s mainsail luff sliders in a 4 metre sea in order to rig the tri-sail! Try doing this alongside in the marina - then use your imagination to see what it’s like in a raging storm - now go practice.

Practice makes (almost) perfect!

It’s no accident that crews are required to raise and set their storm sails before the start of the major offshore races. Take note. If you are fortunate and sensible enough to have a storm jib and tri-sail on board, make sure that you know how to rig them, set them and use them. If you are planning a passage, teach your crew too and don’t find yourself trying to remember how to use these potentially boat and lifesaving pieces of equipment in the heat of battle!

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