Control heel-steer or play the sheet?

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Quoddy

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Apr 1, 2009
241
Hunter 260 Maine
Which is more efficient? The boat is a fractional with a110% jib. If you play the mainsheet during gusts to maintain the angle of attack as the Aw moves aft, won’t the jib stall and create excess heel? On the other hand if you maintain the angle of attack by steering to the new AW then both sails are still working. You won’t get heel from useless stall. Am I missing something basic?
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
Here is something I wrote on another post about weather helm but it also applies to excessive heal. Hope this helps.

Disclosure: I am by no means an expert. I have never taken a sailing class (other then at boy scout camp as a kid). What I am saying is just what I have learned through experience and experimentation and what I have read. So again, please correct me if anything I say is wrong or confusing.

When reaching through sailing close hauled, weather helm is typically caused by the power point on your rigging being too far aft. Lee helm is caused by the power point being too far forward (any of us that go out for the lazy evening sail and just roll out the head sail have seen this). Typically the power is too far aft because most of us have a tendency to over sheet our sails.

So when I have weather helm, or excessive heal, the first step I take is checking my sail trim. I start with the head sail and trim until all tell tales are flying correctly. I follow the three rules of head sail trimming for that. Then I let out the main sheet until it starts to get back winded. The traveler is typically over the center of the boat if you have one. My C&C did not but many of my friends' boats do that I sail on frequently. My main halyard, out haul and Cunningham are typically a little loose at this point.

If I still have excessive weather helm (because you do want a small amount of weather helm) or the boat is healing too much, then I flatten out the main by hauling the main halyard, out haul and Cunningham tight. This depowers the main sail by reducing the sail pocket. If you have a back stay adjuster, you can also tighten this to flatten the sails and depower.

If I still have excessive weather helm or heal, I try moving the traveler to leeward and let out sheet until the sail is back winded to the maximum extent possible. This depowers the main by changing the shape of the sail pocket and "spilling" wind.

Now the sails have been trimmed to the best extent possible. If the weather helm continues, now I will start to think about reefing.

On our C&C, before we added the roller furler, we typically used our 100 jib. We also had a storm jib and 150 genny. We never carried the genny and only had the storm jib when heavy winds (over 18-20 kts) were predicted. So our only option was to reef the main typically. I also did not like changing a hank on sail in the conditions that were typical when it came time to reduce sail.

But when we went to the roller furler, we had the 150 genny cut down to fit on the furler, so it was around 135 to 140 genny. With this set up I found that the full genny was typically causing the back wind on the main earlier then it should be happening without the influence from the genny. So I would furl in the head sail to approximately 75-80% of the head sail area. Now I would retrim the mainsail with the sheet and traveler. This typically would cure the weather helm and excessive heal.

If I had to furl the head sail in to less then 40% of the head sail area, then I would think it is time to reef the main.

I am hoping this same approach will work on my new boat, Catalina 310. But I won't know until the spring.
 
Oct 15, 2009
220
catalina 320 Perry Lake
Don't know what boat you have and maybe it is more tender than my Catalina 320 but adjusting sail trim for a gust seems pretty excessive because gusts where I sail are short lived events. It is much easier to briefly head up through the gust and then get back to your regular coarse and unless the gust is really big, I usually just let the boat heel a little more for the few seconds until the gust has passed. If you are talking about sustained winds then there are many ways to reduce heal-reduce sail, ease the sheet, ease the traveler or change coarse to mention a few.




Which is more efficient? The boat is a fractional with a110% jib. If you play the mainsheet during gusts to maintain the angle of attack as the Aw moves aft, won’t the jib stall and create excess heel? On the other hand if you maintain the angle of attack by steering to the new AW then both sails are still working. You won’t get heel from useless stall. Am I missing something basic?
 
Jan 1, 2006
8,011
Slickcraft 26 Sailfish
If I understand Quoddy's question correctly my answer would be it is faster to release the traveler (And if racing and have crew, the jib) than it is change course to compensate for the change in apparent wind when a gust hits. Also, using the tiller slows the boat down and using it a lot to resist the building helm is slow.
So my answer is that its more efficient to drop the traveler in a gust.
 
Last edited:
Oct 2, 2006
1,517
Jboat J24 commack
We are all generally trying to sail as close to the wind as possible whether we are trying to get some place or racing and a puff of wind will allow you to point higher and keep a good VMG

After you work at it a while you will not even have to think about it

If the puff is still to much then the traveler is step one with dumping the main step two
 
Dec 4, 2008
264
Other people's boats - Milford, CT
I assume that you are sailing close hauled.

Use the helm first. If that doesn't control heel enough without flogging the jib, then you have to ease the sheet. If you are frequently getting hit with gusts requiring sheet adjustments while cruising, I would just flatten or reef the main.
During races we will have crew constantly adjusting the main's angle of attach with either sheet or traveler.

The jib won't stall too much and anyway, a stalled airfoil produces LESS heeling moment, not more.
 
May 11, 2004
273
RAPTOR Hotfoot 20 Ghost Lake
My rule of thumb:
If I'm sailing directly towards my destination I want to keep doing that so I adjust the sail during gusts and maintain my course. Use the traveller if you have one. If not vang sheet the boat. Either method will maintain sail shape, which is important.
If I'm not pointing as close to my destination as I would like I head up during gusts. This allows the boat to sail closer to my destination, at least for a brief period.
The bottom line is I want to sail towards my destination as long as possible
 

RichH

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Feb 14, 2005
4,773
Tayana 37 cutter; I20/M20 SCOWS Worton Creek, MD
The apparent wind direction doesnt have to 'change direction' to make a boat heel more (or less). If the velocity of the wind increases (or decreases) the sail loading will correspondingly change and that alone may cause changes in heel angle.

Changing the shape of the sail by changing mainsheet tension also causes power-up during the 'release' phase of the adjustment ... principally due to sail cloth stretching, the 'shape' becoming 'more full' and distorting in reaction to the new windstrength; and then add to that the inevitable stretch in the 'vang system'.

The 'best' way to adjust for gusts is to use ('play') an efficient and effective traveller in an attempt to keep the boat on an even heel angle - not the mainsheet. The traveller should be powerful enough (and without much friction) so that one can readily, quickly and easily move it in and out and without very much strength used to do so.
 

LuzSD

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Feb 21, 2009
1,009
Catalina 30 San Diego/ Dana Point, Ca.
Roger, that was a really good article and so well written. Your descriptions help so much in understanding what you were doing and hearing and seeing.... I really need and learn from such detailed writing. Thanks alot. Describing what you did with the wheel as you did was perfect, I can imagine the feel as I read.
 

Alan

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Jun 2, 2004
4,174
Hunter 35.5 LI, NY
As usual RichH hit the nail on the head. The traveler is the primary control for gusts, not the mainsheet and certainly not the jib. The only time you would use the mainsheet first is if your boat doesn't have a traveler and the boat is sailing under vang sheeting.
 

Joe

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Jun 1, 2004
8,323
Catalina 27 Mission Bay, San Diego
Quoddy.. my friend.... you asked the same question last year, except you wanted to know how to "play the traveller". So...in gusts, leave the mainsheet trimmed and use the traveller to adjust angle of attack... when the gust passes, pull the traveller back in. If the boat is still overpowered after the gust it's time to adjust the trim on main and headsail. If you want to mess with the headsail during a short gust... be my guest... but usually just easing the traveller down a bit will get you good results and allow you to stay on course.

p.s. if you don't have the traveller....then use the sheet... but get a traveller.
 
Sep 25, 2008
544
Bristol 43.3 Perth Amboy
Velocity lift vs. True wind shift

In terms of picking an optimal course to steer during a lift to optimize your VMG, you do not always want to point up with the "lift". It depends on whether it is an apparent lift due to an increase in the wind velocity or a shift in the true direction of the wind. These should be handled differently.

To know what to do, it helps to have an understanding of polars.
http://www.ockam.com/ocku1.htm

Lets assume you are sailing a windward leg of a race, and the wind is square on the nose to the direction you really want to go. Neither tack is favored. You are sailing at the optimum angle of attack to have your highest VMG. If the wind increases in velocity but does not change its true direction, you will feel an increase in velocity and an apparent lift. Your sails are now over trimmed for the apparent wind. Should you point up or ease your sails?

In the past, I thought that the best choice would be to point up until the telltales on the jib are both flying again. This is not the best way to achieve optimal VMG to the windward mark. To quote Greg Fisher, "ease, hike, trim then point".

The explanation is that you are now sailing to slow for the new wind speed according to the polars. By easing your sails and hiking out (to maintain your angle of heel) you will accelerate to the new target speed indicated by the polar. As you point up, your speed will slowly fall back to the optimal for the polar at that wind speed. In keel boats it is important to try to maintain a constant angle of heel to maximize your vmg. Changes in your angle of heel impacts the flow of water around your control surfaces and keel so you end-up losing lift. I'd ease the main traveller and/or mainsheet initially, then trim it back in as you are pointing higher. On some boats, like a friends J-29 that is fractionally rigged with a bendy mast that I have raced on, you do a lot of adjusting the backstay to alter the main shape as well in the puffs. You'd go to max tension on the backstay in the puff.

If you have a different situation, such as a real lift in terms of the true wind angle changing,
The velocity has not changed, but you are now pointing to low. You need to point up and stay on the best close hauled angle for that wind speed. I would still ease the sails a bit, accelerate as the sails are over trimmed, and as I am pointing up then trim them back in.
 
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