Extreme Weatherhelm

[Racecase]

So I been practice sailing with my mainsail only and have has the issue of extreme weatherhelm. To the point where I cant do anything to prevent the boat from turning straight into irons. If I try to fight it, it just drags the rudder. The conditions were 5-15 knot winds, very calm water, the boat is a 25ft fin keel. I tried adjusting the main halyard, outhaul, leech line, traveler position, and mainsheet. Nothing seems to make a difference. Ive done quite a bit of research on sail trimming and have tried to get the correct shape, draft position, etc but I cant find anything to lessen the weatherhelm when going to windward.
Ive read that it could be excessive growth on the bottom (havent been cleaned in a very long time), maybe a blown out sail, maybe I just need to reef.

Any Ideas on what could cause it to be so bad? Im new to sailing but it makes the boat almost unsailable.

[Alex W]

If you sheet in hard on the jib and let out on the main you should be able to fall off, no matter how bad the bottom is. Does that not work?

What make/model of boat is it? You might want to check the rake on the mast against other boats of the same make and model. If the mast is raked back too far then you will get excess weatherhelm.

[Racecase]

This is only when im sailing with just the mainsail (jib halyard snapped and havnt gone up to get it). But when I was sailing with the jib I didnt have as as bad weatherhelm if any.

The boat is a 25' Watkins, they fore/backstays have turnbuckles but are otherwise non-adjustable. The mast isnt noticeably raked either way but ill take another look.

[deniseO30]

this like your boat? It's a Mast Head Rig. without the jib it's a slug.


Check your rudder bearings they may be binding when under a load.
How you get weather helm with mainsail only is a mystery to me So the jury may want to answer that.

[paul323]

One thing you may want to try is moving the traveller to windward. Some boats are more sensitive than others to traveller position; if the traveller is centered, or worse, to leeward, that can give you weather helm.

The other option - as Denise suggested - is that the rig required the jib to be balanced....

[paulk]

Fix the jib halyard and sail with both sails up. Sailing your boat with just the mainsail up is like turning your boat into a windvane: it always points into the wind because it's not balanced. Even with the smaller fractionally-rigged jib on our boat, when we sail with just the main up, we have to be very careful to keep the boat moving and not head too close to the wind. If we do, we stall out and end up in irons, like you.

[ccriders]

Since you are fairly new here I'll make some assumptions about your knowledge and experience, so here goes, no offense intended.
The shape of your hull creates a "center of lateral resistance" while the sail plan creates a "center of effort". When these two centers are aligned per the designers intents then you would have some weather helm, just enough to be safe from broaching.
When you sail with only the main, the center of effort moves aft and produces more weather helm. When you sail with only the jib, the center of effort moves forward, reducing weather helm and maybe inducing lee helm.
Likewise a main with too much draft (full bodied) will move the center of effort aft creating more weather helm. This is called a "powered up main". Your boat needs both main and jib to be balanced when going to windward, and in the wind ranges you quoted that would be the best set-up. As the wind increases (over 15 kts.), you probably need to reduce the main first by reefing, and then reduce the jib by moving to a working jib or rolling up the jib on the roller furler if you have one. And keep this up until you have minimum sail set. Hopefully you will be in a safe harbor at this point and not need to employ storm weather tactics.
Too much draft in the main can be a problem with an old, "blown-out" sail (one with a big belly), but if your sail is in good condition, then flattening the main can de-power it and relieve weather helm. You do this using the "clew outhaul" and the "cunningham" and the "traveller and main sheet". Also, luffing can de-power it for gusts.
Without a center board you cannot change the "center of lateral resistance" except by healing, so all helm balancing must be done with the setting of the sails or changing the point of sail, lest you make too much leeway. Given you need to go where you are pointed, then your options lie with the set of the sails, and that is where the fun is in learning to maximize the performance of your boat. Too much heel adds to weather helm and loss of rudder effectiveness, so reducing sail lets you "sail on your feet" resulting in better speed, more control and more comfort. Especially for your white knuckled crew.
Some boats can point pretty well with main alone, some with jib alone, but all boats point better with main and jib balanced for the conditions.
Hope this helps.

[Alex W]

One way to think about it is that sailing with the main only is like being on a weather vane.

The CLR is the keel on your boat, or the swivel on the weather vane. Almost all of your sail area behind that swivel point (like the tail of a weather vane) and so all that the boat wants to do is turn into the weather.

Add a jib and you'll lose the weather helm.

Sailing main only is also more dangerous and harder than with the main and jib. It is easy to do an accidental jybe (which is dangerous) when sailing with main only. With the jib you get a strong warning signal when the jib is blanketed.

[AirborneSF]

My 26' does this all the time on 'main' only also. I've been told if I don't have the jib up, to try and ease the main till it lufs and then sheet in slow till the boat starts moving. .02

[celenoglu]

Is it probable that you keep the main too much to the center. Although it needs to be almost centered when you have the jib, it needs to be free when using only the main.
The jib causes the wind to change direction so you need the main almost centered. With main only just increase your boom angle with the boat.