Sail trim for cabin yachts on the IJsselmeer.
Sail trim is not something that one immediately thinks of during a sailing trip. Of course there are sailors who always make a competition of touring sailing, and don’t really want to admit this. These sailors can always be recognized by their active and restless trim, and when they come close they suddenly start scrubbing the deck to pretend they weren’t trying at all…
Admittedly, everyone has something competitive deep down inside, and everyone wants to sail past another boat.
Sail trim is not only important for those who want to sail fast, but also important for sailors who want to sail safely and comfortably on the water. In many cases not all crew members are equally seaworthy, and in order to have a nice trip it is therefore important to have the boat well under control by trimming the sails in the right way!
Families or groups who rent a boat can also get even more fun out of their sailing holiday or weekend by trimming the boat correctly.
A problem with ze-trim in general is that every ship reacts differently, so the trim per boat is slightly different.
Below we discuss a number of trim options that are relevant for the sailing ships we have in our fleet, such as Dehler and Bavaria.
Trim of the jib or genoa:
The most important thing is the right choice of sail. Ideally, we have several headsails to choose from, so we can always hoist the right sail. However, most sailing yachts are now equipped with furling jibs and furling mainsails.
This is wonderfully easy to sail with, and you don’t have to clean up anything in the harbor, you pull the furler line and the sails are gone!
We must therefore assume a headsail that is easy to adjust on the one hand, but which on the other hand will never be optimal. Rolling jibs are generally made quite flat, this is necessary to be able to roll them up. The foam strips in the luff are made to better roll up the bulge in the jib.
This makes it possible to only partially roll out the jib when there is a lot of wind.
The flat sail shape is ideal in high winds; the boat is less inclined and nice and close to the wind. With little wind it is just a bit more difficult. This is not a problem as long as you realize that you should not screw in the sheet too close, but rather let the jib “breathe” a bit and leave the sheet relatively loose.
By also steering a few degrees lower, you will see that you are sailing a lot faster. Due to this extra speed, the keel will also work a bit better, so that the ship will lose less weight and therefore you will be cruising faster than boats that steer (too) high into the wind with closed sails.
In the breeding we can set 3 things; the drop tension, the position of the genoa cart and the bolt tension.
The fall tension should be a bit tighter in high winds, and looser in low winds. The jib actually has the profile of an airplane wing. The best is to have the bulge in the jib at about 30-40% from the luff. If the jib trap is too loose, the bulge will go further back, and may even come behind the center. This is disastrous for the boat speed. Because the bulge is in the back of the sail, the jib will “create” more and the wind will no longer discharge nicely, so that the boat is only slowed down and also tilts.
So make sure that the curvature is neatly in the front by means of a correct drop tension.
The genoa cart can be adjusted forwards and backwards. The more it is adjusted forward, the closer the jib gets to the rump. With an average wind of force 3-4 it is fine to put the cart fairly far forward. The boat will have a good speed because there is enough wind and not too many waves, and because the leech is a bit closer you can steer a little higher without the speed dropping immediately.
When there is little wind or a lot of wind, the cart can go backwards.
This makes the leech looser, or “open”, so that wind is discharged. This is nice because the boat will then tilt less and the wind gusts will provide extra speed instead of extra slope.
When there is little wind, it is important to put the cart backwards and to loosen the sheet a bit. This increases the angle of the jib in relation to the boat, giving the boat more propulsion and less slippage.
Another reason for an open leech (also called Twist) is that the wind at the top is always wider than the wind just above the deck.
The wind at the top is always stronger, and is therefore less affected by the apparent wind of the boat. A bit complex story perhaps and not entirely relevant for touring sailors.
The sheet tension should be tight in high winds and loose in low winds.
In low wind it is important to keep the boat speed and in high wind it is important to make the sail as flat as possible.
When there is a lot of wind it is very important to put the genoa cart backwards so that the rear end opens nicely at the top.
Trim of the mainsail:
The mainsail also has a number of adjustment options: mainsail drop, landing and sheet tension.
It is important to understand that the jib or genoa generally provides speed and propulsion, and the mainsail allows the boat to gain height.
Make sure the mainsail is reefed when there is a lot of wind! A mainsail that is too large directly affects the steering characteristics of the sailboat, making steering very difficult with waves and gusts of wind.
Some boats such as our Dehler 37 or Dehler 34 have a relatively large mainsail and will have to be reefed faster, while the Bavarias are less sensitive to this. This sails wonderfully when there is little wind, but you have to reef in time when there is a lot of wind.
The Dehlers have an added advantage; a flexible mast that allows you to make the mainsail very flat by tightening the backstay, so that you don’t have to reef as quickly.
The fall tension has the same function as with the jib; more tension causes the bulge to go more forward, and less tension causes the bulge to go backward.
With the mainsail it is nice if the bulge is 40-50% from the luff.
in strong winds prefer a little more forward, so that the mainsail “discharges” the wind better and the boat is less inclined.
Less drop tension also ensures that the sail becomes a bit more rounded, which is of course very pleasant when there is little wind.
The overflow can usually be adjusted; In low wind, the landing may be slightly above the center of the boat, and slightly below the center of the boat in high winds.
By pulling up the landing and slackening the sheet, the leech becomes a bit looser or “open”, so that the boat accelerates better.
When the boat has enough speed, you can lower the landing slightly and tighten the bolt tension slightly, allowing you to steer higher, while maintaining speed.
When there is a lot of wind, it is wise to set the landing a little lower and tighten the sheet. The front part of the mainsail will flap or bounce, but the rear part will continue to catch the wind. This reduces the size of your sail, as it were.
The sheet tension is therefore actually the same as with the jib; less tension in low wind and much tension in high wind.
Do you want to know more about sail trim? Book one of our skippers for a few hours, and get even more out of your sailing holiday!