Genoa size vs. benefit

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Figment
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Genoa size vs. benefit

Post by Figment »

Rather than take the meandering Genoa Cloth Weight thread in a decidedly nerdy direction, I figured I'd do it down here in the nerdery.

Of course as we bat around all of these different sail sizes, I can't help but do a few drawings. I took a rasterized image of the Triton sailplan and overlaid my current sail inventory, and then drew in the sails I think I'd like to have for comparison.

I'm struck by how very little difference there is in sail size in the upper end of the spectrum.
This mythical 180/drifter has only 25sf (11%) more area than a 155.
The 155 has 35sf (20%) more than the 135
The 135 has 40sf (30%) more than the 110
The 110 has only 11sf (8%) more than a "blade" (but let's recognize that a blade is a blade because of the flat cut, not because of its area)

This is the nature of a fractional rig, of course. Short luff limits the impact of increased LP. Looking at those numbers, I'm a bit dubious that the 180 really gives remarkably improved performance over the 155.

I'm thinking that a versatile 3-sail suit includes the 155, 120, and blade.

For a "drifter" to have a meaningfully increased area, it either needs to fly from the masthead or it needs to be a 200+.

How nutty am I? ;P
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Post by bcooke »

I'm a bit dubious that the 180 really gives remarkably improved performance over the 155 ... How nutty am I?
Question 2: Well, you are posting in the nerdy section of an arguably nerdy forum. Can we leave it at that?

Question 1: As for the sail #'s. I agree. A person can overthink this. The days of a Triton being speedy are in the past so getting too fussy about the sail inventory might be time mis-spent. I already wasted a lot of time thinking about this and in the end I stuck with the 140 the boat came with and a 100 for those windy days when I am on a schedule and need to get going. My boat came with a good spinnaker that I would never use so it became an assymetrical. Without the spinnaker I would consider a masthead drifter and plan on motoring up wind rather than face the interference with the jumper struts.
I'm thinking that a versatile 3-sail suit includes the 155, 120, and blade.
I hear raves about the blade but without much experience I stuck with a regular working jib. I think I would split the difference between the 150 and 120 (say 135) and add a true light wind sail. Truth be told though, your plan sounds as good as mine. As long as you have good coverage from light to moderately strong winds I would say you are okay. I don't think there is any one way to do it.

-Britton
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Post by jollyboat »

if you have a decent roller furling unit on the Triton consider a 170 % roller furling "reefing" genoa. Make this sail out of 5.5 ounce and it will be a decent all purpose #1 When you are talking about sails you really have to take into account where you are doing most of your sailing and what kind of sailing you are doing. Today I am designing a 170% LT #1 made of Demension Polyants 'FLEX' at about 4.5 ounces because I am sailing in Western Long Island Sound where the breeze is typically light 5-12. I want as much sail area as I can get with as much performance as possible. While I was sailing my Triton in the San Francisco Bay, I only used my 95% blade. I will work out the sail areas today and exact increases in sail area for several sizes. If I were to only have a four set in my inventory for daysailing and coastal cruising in the Triton it would be Main, full batts, reefs, 155 AP roller furling reefing headsail, blade jib, and 1.5 ounce 165% cruising asymmetrical spinnaker. With this combination you could do a lot of great sailing. If I could add one more it would be a 170% light #1
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Post by jollyboat »

figment - i have your stern pulpit - it needs a little work but it works if you are interested
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Post by Tim »

Personally, I think an inshore cruising boat needs one decent all-around sail set on a furler.

Discussions about extra headsails therefore seem redundant to me, other than having a much smaller headsail available for the furler if you really needed minimal area beyond that which the furler could reasonably produce. For most coastal sailing, this is probably unnecessary, though.

Obviously, I know that not everyone wants furlers. But changing headsails on a pleasure sail or cruise just seems like unnecessary work to me. Life is so much easier when you just need to pull a line to reduce sail area. But as usual, everyone has their own requirements, and if people choose not to use furlers that's fine with me. I understand both sides of the coin; but the coin always lands on the "furler" side for me. Other peoples' coins seem to be weighted differently and fall on the "hanks" side. Good enough.

Obviously racing brings different requirements. But we're generally talking about cruising here. Racing boats should have multiple headsails because every 1/4 knot really matters.

That said, I think a high-cut 155 on a furler might be about ideal for a cruising Triton. You can reduce this sail to about a 110% with relative effectiveness; along with one or two reefs in the main, this pretty much covers just about any wind speed you might reasonably expect to encounter. Then, perhaps having a good blade would round out the upwind headsail inventory, if you want to beat into winds in the 20+ range. I'll stay cozy in port on these days, myself, or head offwind with the partially-furled 155.

Offshore requirements are completely different. But that's not what we're talking about here either.

I have sailed with my 130 on the furler for 5 seasons, and it is generally a good choice, though this particular sail has never been anything special thanks to the sailmaker ignoring my specifications at the time of build. Something a little larger might be better next time, though, since reefing the main is really a better way to reduce sail on a Triton anyway.

I agree that a truly effective large headsail, particularly of the drifter variety, really should go to the masthead. The jumpers are a real hinderance to this, though.
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Figment
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Post by Figment »

Britton by "how nutty am I?" I really meant "Folks who know infinitely more than I do about this stuff (George, Brian) please teach me something."
But yeah your point is valid of course. ;)

Tim your point about how depowering the Triton is primarily about the main is well taken. My energy and money are probably better saved toward a proper full-battened main. I'm sure I'm putting entirely too much thought into this foresail realm.

Brian, thanks for chiming in. I'm not yet prepared to surrender to the Forces of Roller Furling, but I your strategy of 155, blade, and drifter has informed my process.
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Post by jollyboat »

[quote- TIM L. - "Discussions about extra headsails therefore seem redundant to me, other than having a much smaller headsail available for the furler if you really needed minimal area beyond that which the furler could reasonably produce. For most coastal sailing, this is probably unnecessary, though."]

I agree with Tim on this point. A good furling system is a very nice addition to any sailboat and a well made genoa that suits a sailing need that can be reefed will handle 90% of what most of us will call for. With this said, a lot of new boats - like Beneteaus are being offered with a basic three sail inventory which reflects this.

In concern to the Triton in light air it is a suprisingly able craft even with just a main and jib, especially in smoother water. As with any boat though having the ability to fly the "whomper" (WIND) is really, well - 'cool' -
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Post by Summersdawn »

I don't know if price is a factor in your decison about furlers, but I bought a furler 3 years ago for my boat. I absolutely love it. Not only is sail handling much easier, but it freed up alot of room in my boat that used to be taken up by sail bags. Now I carry main (flaked on the boom with cover of course), 150 on a furler, and crammed under the v berth, an assymetric (in a spot that I normally didn't use for anything else).

The furler I bought was a Simplicite Furler. It is a very simple, very rugged roller furler/roller reefer. It uses its own halyard. What I like about this one is the fact the extrusion clamps on to the swages at both the bottom and top of the headstay, so increasing backstay tension also increases (to some extent) halyard tension. I'm not sure if on a fractional rig, you would get as much of a benefit from this though.

It was very affordable - shipped from Quebec to my home in British Columbia, with taxes, was just over $900 Cdn. (I believe I got 30' of extrusion). It is also guaranteed for as long as you own your boat.

Here is a link to there website - http://www.alignement.com/simplicite/
Rick
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