The missing link

SOMETIMES I WONDER if there’s a small part missing from my brain. It’s the part that deals with heeling in a sailboat. Specifically, it’s the part that can understand why a boat with a low, spread-out sailplan should heel less than a boat with a tall, narrow sailplan.

I have read innumerable times that a gaff-rigged ketch with a bowsprit will heel much less in a wind of a certain velocity than will a high-aspect-ratio sloop. And for the life of me I can’t see why.

Now let me say straight away that I understand the extra leverage gained by a long tall mast of a sloop, compared with the stumpy masts of a gaff-rigged ketch. I accept, too, although with some cynicism and doubt, that the wind at the top of a mast blows harder than the wind at the bottom.

However, there can be no gainsaying the fact that it takes a certain amount of energy to move the mass of a sailboat through the water. That energy comes from the wind, and if the wind is abeam, or forward of the beam, it tends to make the boat heel to leeward.

Surely it takes the same amount of energy to make similar hulls heel over to the same number of degrees, no matter whether the sails are high or low, doesn’t it?

Obviously, the higher the center of effort, the less sail area is required to make the hull heel over. In the gaff-rigger, more sail area will be required to achieve the same amount of heel because the center of effort is lower, and the sails don’t have as much leverage.

In other words, the sails of the sloop are more efficient since they create the required amount of heeling energy with less sail area.

Thus, to say a low-lying rig will produce the same amount of energy (which translates to the same sailing speed) with a lesser amount of heel is nonsense. If the gaff rig doesn’t produce as much heel, it also lacks the ability to create energy to move the boat forward. In other words it lacks sail area. And that is surely not something to crow about as if it were the best thing since sliced bread. Whether your sail is tall and thin, or low and wide, it needs to produce the same amount of heeling energy.

If you were to take this questionable theory to its limit, a boat with sails a foot high and 100 feet long would cause no heeling at all. And very little forward motion.

Once a canard like this starts making the rounds, it gets repeated thoughtlessly by a thousand copycats eager to show off their new knowledge, and soon enough it becomes part of the accepted lore of the sea.

I really wish I, too, could accept it. I don’t like to stand out from the mob and be jeered at. But my sadly incomplete brain won’t let me. You won’t believe how I suffer.

Today’s Thought
The flying rumours gather’d as they rolled,
Scarce any tale was sooner heard than told;
And all who told it added something new,
And all who heard it made enlargements too.
—Pope, The Temple of Fame.

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“Oh yeah, what is it?”
“She lies about her age.”

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Sailplans and heeling

EVERY NOW AND THEN I come across a comment in the yachting literature that puzzles me. One that pops up quite regularly is this: a long, low sailplan causes less heeling than a tall, narrow sailplan.

I don’t buy it. I can see where it starts, though. It’s all about leverage. It’s quite obvious that the taller the mast, the longer the lever, and the easier it is to make the boat heel over.

But something deep down inside me keeps saying that’s not all there is to it.

I readily confess that I lack the mathematical and engineering skills to work this out logically. Hell, if I was that clever I’d have a decent job instead of being a writer. But listen up for a moment, will you?

To make a boat heel to a certain angle there must surely be a certain fixed sideways force. It is the combined sum of all the sideways forces experienced by the sails at different levels all the way up the mast. Now I can’t see why it matters whether those sideways forces are generated higher up, as in the case of a high-aspect-ratio racing mainsail, or lower down, as in a gaff-rigged yawl with a long bowsprit.

I’ve tried to see why it matters but I have failed. It’s the force that’s generated that matters, not whether it’s generated high up or low down. So I am still very suspicious of any statement that claims a low sailplan leads to less heeling. If, in practice, it does, it can only mean that there isn’t enough sail area in the low sailplan. I think this whole thing belongs in the category of marine urban legend and I wish people would stop repeating it and spreading a misleading myth that makes me mad to think about. Well, not mad, but it does irritate the hell out of me.

I will grant you that a long, low sailplan makes it easier to balance the boat for weather helm. I will grant you that the gaff rig is powerful off the wind and well suited to many offshore cruising hulls. But I don’t want to hear any more about its causing less heeling, if you don’t mind.

The willful perpetrators of this myth presumably think that heeling is bad for a sailboat’s performance, otherwise they wouldn’t bother to crow so loudly about the benefits of a long, low rig. But that’s not altogether true, either. If a boat has long overhangs, heeling helps raise the potential hull speed by lengthening the waterline. On the other hand, as dinghy sailors know full well, heeling spills wind from the sails and robs a boat of some of its motive force.

That’s the trouble with sailing. You never know what to do for the best until someone comes sailing past you with a big smirk on his face. Only then do you know that what you are doing is wrong. But by then it’s too late.

Today’s Thought
We hold rumour
From what we fear, yet know not what we fear.
But float upon a wild and violent sea
Each way and move.
— Shakespeare, Macbeth

Boaters’ Rules of Thumb, #95
Galley stove gimbals. If your gimbaled galley stove has only one pivoting axis, it should swing sideways, that is from port to starboard. If you install it so that it swings fore and aft, it will incline as the boat heels and everything will slide off. Single-burner stoves gimbaled in both directions don’t have this problem.

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