Why do we reef and what does it achieve?

When sailing in a normal breeze (Beaufort Force 3 / Force 4) it’s likely that we would have a full mainsail and a full headsail. If the wind strength increases, the yacht will become over-canvassed, it will heel over more than desirable and it will start to slip down wind (leeway). The best way to tell if a yacht is overpowered is to ask the helm. If the yacht seems to want to turn up to the wind and the helm is using significant correction to keep it on course (weather helm) then you should be considering taking a reef.

Reefing is merely the reduction of the sail area being used. Many yachts have more than one headsail and so simply removing one headsail for a smaller one will have the effect of reducing sail area. Alternatively, the headsail may be set on a roller reefing system which allows the sail to be partially ‘furled’ away in part or whole. In many cases the foot of the headsail will be marked at suggested reefing positions.

However, the mainsail is a rather more permanent fixture when sailing and cannot be easily replaced by another sail, even if we carried one. We therefore have a reefing system in place. The mainsail is traditionally reefed by dropping the sail to a metal ring sewn into the sail called a ‘cringle’, located on the luff. The halyard is then re-tensioned and then the back of the sail (the leech) is pulled down to the boom with a separate line known as a reefing line. Most mainsails have two or three reefing positions. This sort of reefing is called ‘slab reefing’.

Other methods of reefing the mainsail include in-mast furling and in-boom furling.

Reefing to the prevailing wind strength and point of sail will help you maintain optimum course and speed as well as protecting your vessel and sails from damage and making for a more comfortable ride for your crew.

To learn more about sailing take a look at our range of RYA Sailing Courses.

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