Performance Reefing?


How to trim roller furling sails when reefed  (published June 2013)

Like it or not, furling sails are the new norm. Sure, furling headsails have been around for years, and to a lesser extent so too have in-mast furling mains. But now they are commonplace on the vast majority of production-built cruising sailboats, which means we need to know how to properly reef them for heavy weather performance.

For many cruising sailors, reefing and performance aren’t synonymous with one another for good reason: when it starts blowing, we just reef down and sail. But, when your sails are reefed they take on a completely different shape and that shape still helps drive your boat. Here is an overview on furling sails and how they can be trimmed when the wind is up and a reef is in.

Look through the immense variety of cruising sailboats hitting the market today and you’ll notice one thing: in-mast furling mainsails are not only common, they’re standard issue. In fact, due to the high demand for easy sail handling, most manufacturers are equipping their newest models with an in-mast furling main and making a standard main optional—instead of the other way around.

The primary reason that in-mast furling mains have become so popular is that they are just plain simple to set and reef. Gone are the days when a crewmember went forward to jump a halyard and grind from the mast to raise the main through a web of lazy jacks, then drop it down, wrestle it to the boom and cover it up. With a furling main, one or two people can quickly and efficiently set and shorten sail from the cockpit with little chance of a problem. Like most things these days, in-mast furling mains have been around long enough for manufacturers to work out virtually all the kinks in these systems.

Opponents to this shift say they don’t trust the roller furling mechanisms to do their job in all conditions and failure makes them harder to operate, not easier. I certainly understand that critique, but the same criticism was once leveled against the roller furling headsail and look how that turned out. In reality, the mainsail itself, not the furling mechanism, can cause the system to jam. And the major cause of a failure isn’t typically the sail or the mechanism; it is user error, as owners and charterers aren’t familiar with the furler’s nuances. The other thing to consider is that manufacturers aren’t putting roller-furling mains on 25-foot gunkholers with small mains that are easy to raise and lower by hand. No, they’re going on bigger boats with tall masts and thus, larger sails. And at some point, those big sails need to be reefed.

When teaching students on boats with in-mast furling mains I try to focus on smooth sail operation before we talk about sail trim and reefing. By having them set and then furl the sail multiple times prior to sailing, they get a sense of how the furler operates and how much load is being put on the outhaul, inhaul and boom vang. It is also important for them to watch the sail go in and out of the mast so they can see if any snags are happening. If the sail has battens, that can be a trouble spot as they enter and exit the mast.

Just like on a standard main, when the wind builds into the upper teens and breaches the 20-knot mark it is usually time to reef a roller furling main. Most rigs, furlers and sails have pre-set marks as to where the sail should be rolled to for the first or second reef, so check the manual before setting out.

The best way to reef an in-mast furling main while underway is start close hauled and foot off the wind just slightly while easing the mainsheet. Leave the jib where it is and that will cause the main to backfill with wind—you want the main to luff, not flog. Now that pressure has been eased off the sail you are ready to take in as much sail area as you need. Remember to ease the boom vang because as the sail furls, it will get higher in the mast causing the boom to rise with it. If your boom vang is too tight you won’t be able to roll the sail in or out properly and may actually break the boom vang if too much pressure is applied. Also, keep a little tension on the outhaul as you furl to ensure that the sail rolls in smoothly, and again, watch the sail as it enters the mast.

When your reef is done, power the main back up and look at its shape. The foot should be flat but not too strapped to the boom. Even though you are reefed it is good to retain a little shape to keep you sailing efficiently. Now is the time to snug up the boom vang to make the leach tighter and, if you are still overpowered, reach for my favorite performance control—the traveler.

A sailboat’s traveler is one of the most effective sail controls to use when your boat is overpowered, as it changes the sail’s angle to the wind or “angle of attack.” By moving the boom to leeward in heavier wind, the traveler helps to reduce pressure on the main, while keeping it working at the same time. With a reef in the main, and the traveler down you will undoubtedly be sailing flatter, faster and more comfortably than with a full main.

Furling headsails have been around for a while and these mechanisms have been refined in such a way that if used properly, they are virtually impossible to get wrong. Again, the detractors out there will cry about them not being traditional and that if something goes wrong you’re stuck, but you’re really not. The sail can be raised and lowered in its track on the foil almost as easily as a headsail on hanks.

Besides knowing how to properly use it, the key to having a smooth running headsail furler is maintenance and making sure that it is properly set up. Start by inspecting all the working parts of the furler to ensure they are in good repair. Next, take a look at how your furling line is led aft to the cockpit. It should run smoothly through blocks and should not have any areas where it is chaffing. Also, consider upgrading the furling line to one with less stretch, as that will keep it from binding in the furler if it gets too tight.

Then take a look at your sail. The luff of a furling headsail should have an area of foam on it to help retain a nice shape when the sail is reefed. Also, your halyard should run through a halyard restrainer on the top of the mast so that it does not wrap around the stay when the sail is furled. This is especially important on smaller sails where the head does not make it all the way to the top of the foil.

Reefing a headsail isn’t hard, but it isn’t as easy as just pulling the furling line to take in some sail. I have noticed cruisers trying to rollaway or reef their headsail while flogging head to wind. Not only is that bad for the sail, but it puts more pressure on it too, which creates a lot more work for the crew. I have also seen the opposite where the jib sheet will get released while sailing downwind allowing the headsail to fly forward of the boat. This will also create more work and may even cause the sail to get wrapped around the headstay.

Needing to reef your headsail means it’s windy, which also means there is a lot of pressure on the sail. So your first task when reefing the sail is to take pressure out of it. By far the best way to relieve pressure from a headsail is to turn down to a deep broad reach to blanket the sail with the main. Once the jib or genoa collapses in the shadow the main, hold course and furling will be infinitely easier for the crew.

Performance-wise, the problem with reefing your headsail is that it turns it into a really nasty, inefficient shape for the given wind speed. It becomes bloated and full, which doesn’t allow you to sail as close to the wind and causes uneven pressure on the forestay. In an ideal world, changing to a smaller jib would allow you to keep an efficient shape, and many blue water boats have an inner forestay set up for that very purpose, but that can’t always be done.

The next best thing is to change the position of the fairlead cars on their track. When reefed, the entire sail moves forward, so you need to do the same with the fairleads in order to change the sheeting angle to pull evenly through the middle of the sail. Moving the fairlead forward will help your upwind and downwind performance because the top of the sail will not be luffing off and flogging. Beware of putting the fairleads too far forward though as you don’t want to make the sail any more powerful by pulling tighter on the leech.

Reefing is a necessary part of seamanship that every sailor should be comfortable with whether they have roller furling sails or not. Because the trend has shifted towards in-mast furling mains, learn how to use yours properly or if you plan to charter or buy a boat with one, make sure you are trained on how the furling mechanism works. And when reefing your furling sails, don’t forget about sail shape to keep you moving fast and efficiently through the water.