E-25 Heel Angle & Performance

This weekend I went out in 12-14 knt winds and with a reefed main and about a 90% jib (roller furling) I managed 4.2 - 4.7 knots measured by GPS (WAAS enabled). Later, when sailing downwind with the same sail configuration and wind strengths I was being pushed along at 4.7 - 5.0 knots, which surprised me. I thought the upwind speed would of been faster...so why wasn't it? I tried to limit heel when sailing upwind, and I thought my sail trim looked good for the conditions, or is it normal for the E-25 to have upwind and downwind speeds about the same?

It's normal for any boat to be as fast or faster downwind. Especially in a stiff breeze, or with some chop, the boat will go quite a bit faster downwind than it will go to weather.

Beating often feels faster because the apparent wind in your face is faster. And in very light conditions you may go faster close hauled than dead-downwind, but that's the exception. When it starts blowing, and you get a good swell the speed is definitely off the wind. I've gone 12.5 knots downwind in a good blow, when upwind I'd have been hard-pressed to maintain hull speed.

Speed

Right on, Nate! To explain this a bit further, it is true that running is the least efficient point of sail-it is the only time when you don't really have attached flow over both sides of your sails, and are literally being pushed by the wind-which does not provide a lot of motive force.

The second least efficient point of sail is beating to windward-not because there is no attached flow-there should be-but the lift being created by your sailplan is in a direction VERY divergent from the course you are steering-so while the sails are producing lots of lift-only a little of it is in the "right" direction.

Far and away the most efficient point of sail is reaching-beam to broad reaching-where if trimmed right, you have the majority of lift created by the sails aligned with your direction (sails are eased)-so most of that lift, or motive force is being used efficiently.

While all this is true-as Nate says this is all affected by several factors-as he says, the apparent wind is highest when beating, so this will partially offset the inefficiency-especially in lighter air as Nate describes. That effect is reduced in heavier air because as the boat reaches it's top speed, the apparent wind no longer increases as much (since the faster you go, the more there is). When running (the slowest point in light air by far), as each tenth of a knot of speed you gain directly reduces the apparent wind speed-limiting how fast you can go.

Reaching is magic, becuase you start out with an efficient orientation of the sails to the boats' direction, then, unless you are very broad reaching, as you accelerate, the apparent wind goes forward, then begins to increase-but unless you are really close reaching, it should not go so far forward as to require sails to be trimmed to the point of "aiming the lift" away from your direction-but you will get more apparent wind, more lift, etc-

The only speed producing benefit to running is with waves and good breeze-but in this case, the waves increase your speed, which pulls the apparent wind forward, which causes you to trim the sails, which (re)establishes attached flow, which creates lift again, and off you go!!

Well said Nate!

You have my attention

You are addressing two areas where I feel a real lack of knowledge, and I would have paid some money to have had Seth on board two days ago when we turned a mark and faced a beam reach in company with two competitors. Most of the literature addresses optimising trim and tactics for spinnaker boats, but for our JAM racing much of that doesn't apply or has to be modified. In such a situation, with the genoa eased and sheeted forward, I can get good flow on the lee tell-tales but it is very hard to find a sweet spot for the windward ones, and I usually end up pretty much ignoring them - they just spin or flutter regardless of sheeting, unless the sail is brought in way too far. By the same token, I can get real good flow off the leech of the main, but over what seems to me to be an overly wide range of trim. I tend to sheet it out as far as I can and still keep the tales streaming, but can't tell a lot of difference in boat speed at that setting. Admittedly, on our lake the winds are rarely constant, so it is often tough to tell for sure what difference a trim change really made. Thats area of confusion # 1.
Area # 2 is when running for a mark that is ddw in light air. I try always to keep the tales moving, which means steering high. But on a heavy boat with no chute, I know that technique is not as effective. With the sails winged out, however, I'm just not happy unless I see those leech tell-tales streaming some. Seth, I know you have said before not to obsess over this, but it just seems to me that developing some (even if it's not much) flow over the lee side of the main HAS to be better than pure drag. My crew is more experienced than I, and has a number of club championships under his belt, and he is a strong proponent of "heading straight for the mark" in those conditions. But it is hard to make myself do it when I'm the guy moving the steering stick.

Send checks and airfare to......

Hi Bob!

When you are beam reaching(or close to it-NOT DDW), you are right that you want to ease the headsail-WITH the lead forward. How much? We have discussed having the sheet be angled such that if you continued the line from the block and "through" the clew, it would hit the headstay about 55-60% of the way up. Another method, is to ease the sheet as you bear off like you normally would, using the LOWER telltales as your trim indicator at first. When you are at the desired sailing angle, and have the sail trimmed well at the lower set of telltales, you will notice that the top of the sail is luffing at this setting, or at the minimum the upper set of telltales indicate a huge undertrimmed condition. Simply move the lead forward until the top set behaves like the bottom set-you will then have the lead properly located for the sailing angle. Check it by easing the sail a bit too much, and the windward telltales should break (lift) together (at the same time), OR it is fine for the top set to lift JUST a hair before the lower set-but not much. If the lower set breaks first, then the lead is TOO far forward. Once this is done-ease the main until it begins to luff, trim just so it stops, and make sure you have flow off the leech (by making sure you don't have too much vang loading). If you find the top of the main is luffing while the bottom looks good-add some vang until the top and bottom behave in the same way-just like with the genoa leads. You will now be so close to perfect trim that trim is no longer your concern.

However, when VERY broad reaching (almost running), the deeper angle you get to, the less effective and reliable the telltales will be-especially if your sail is a bit too heavy in weight for the wind speed and/or wind angle. So, there will come a point where the telltales simply are not worth fussing with-especially if you have the heavy sail situation-they just run out of effectiveness-and think about this-the deeper you get-you will at some point have the air entering the sailplan at the LEECH of the sails instead of the luff-When ddw, this is the case for sure with the genoa, and sometimes the main.
This obviously makes any conventional interpretation of the telltales incorrect.

So, when running wing and wing (truly wing and wing-as opposed to reaching with the genoa poled out) STOP worrying about flow!! If you are really ddw-just tweak the genoa/whisker pole so it "feels" fullest, and push the main ALL the way out. Telltales will not help you one bit in this condition-they may or may not fly, but when ddw, the fact of them flying or not is not indicative of anything. If you reach up 10-20 degrees, keeping the pole wung out, then yes, work the sail to get the telltales at least flowing off the mainsail leech.

This is why Bob has to let this go-the flow over the leech may indeed have become the "leading edge"-fuhgeddabouditt. At least when sailing really deep.

As far as "straight for the mark" goes; sometimes yes, sometimes no. Depends on the boat, the wind speed, waves, etc. Are there conditions when it will work on your boat-espeically in JAM? Yes. Even without "flow" it might be the call in the right conditions.

But, as we have said before, to chase these trim points to this level is extremely difficult without a high resolution knotmeter. The changes we are talking about yield .1, or .2kt. benefits. You can't feel this and you can't see it on a round guage instrument-you need the digital readout with better than .1 resolution if you want to work at this level of precision. A person could drive himself/herself nuts chasing these things without this tool-and we should be having fun, right?
Fair winds!!

seth always has great advice.

In the light airs of Santa Monica Bay, with our little, heavy 32-2, we have found through trial and error that rounding the windward mark and heading straight for the leeward mark is the fastest way, even if we go really slow. We can double our boat speed by heading up and reaching, but in order to do that we have to maintain a wind angle of at least 130-140 degrees and, in light air, our VMG is ALWAYS slower when trying to sail broad angles. Our boat simply doesn't have the ability to plane or accelerate at sufficient speeds to benefit from sailing the longer distance.
We have been able to significantly improve our DDW performance though, in non-spinnaker mariner class events, by throwing the rig forward (i.e. releasing almost all backstay tension and even bracing the rig forward by tensioning the spare spin halyard which is attached to the bow pulpit), moving the jib cars forward, easing both main and jib halyards and keeping crew weight in on the centerline. We also tried creating a little more fullness in the main by easing the outhaul, but then decided that more sail area exposed to the wind is better, so we create the fullness in the sail by reduced halyard tension, rather than easing the outhaul. We may still back the outhaul off by an inch or so, but very little in comparison with what we used to do.

When sailing very broad reaches or DDW, I never steer by the telltales. I love driving upwind, when the telltales and the swells are basically the ONLY things I watch, but as we come off the wind, I generally steer to the mark and let the trimmers take care of sail trim. When I trim on reaches, laminar flow on the leeward side of the sail is my primary concern. I don't mind a little flutter on the windward tails, but I use a combination of sheet tension, car position and halyard tension to acheive the optimal shape.

just my two cents.
Love these race tips.

Jim McCone
Voice of Reason E-32-2 Hull #134

Nice work

Jim,

I can't think of any 32-2's in recent history that have been raced as hard and as well as you are doing-great job!

You are really sailing this boat well-and while I believe that you are doing better by going ddw-math would suggest that if you really doubled your speed by getting the wind to 140 degrees, you should net better VMG this way...But that is OK-I doubt it is actually doubled, and your general observations are right.

You are 100% correct that the heavier the boat, the less benefit sailing hotter angles gives you in terms of VMG downwind. Even recently (well, the 70's and up to the mid 80's) the IOR race boats (considered light in their time) always sailed as deep as they could to get the best VMG-and we had to use those awful Blooper sails-yuck!. Transpac was miserable on these things-as we were sailing ddw in big air on boats that were horrible at those angles ("death rolls", crash gybes, etc). The skill needed to steer these things fast, yet on the edge of control was hard to come by.

Today's race boats, with wide powerful stern sections, lighter displacement, and fairer overall lines, are a delight, and by heading up 15 degrees, will really jump in speed-and sometimes even plane-netting much better VMG while sailing more miles (but with many more smiles).

Back to your boat-I think if you were sailing with spinnakers, you would see some benefit in the very light air by reaching up a bit-but once the boat is over 4 or so knots of speed, I would agree to go as deep as you can.

If sailing JAM-I think you are doing exactly the right thing.

BTW-your discussion on outhaul tension was right out my "book". Old schoolers always said to "bag" the main by easing the outhaul when reaching and running....But why would anyone want a BAG for a sail? And yes, easing the outhaul excessively does reduce projected area, and when you are running ddw-that is all you have to work with, so again-nice job!

My rule of thumb is that for a fairly fresh sail, I have about 2-3 inches max of adjustment on the outhaul-beginning at max tight. I may ease it an inch or so in light air upwind or reaching-because at low speeds, a fuller sail can create more lift (or enough to offset the added drag of the fuller sail) to get you going. But once the boat is trucking, the main should get flatter the faster you go. Downwind in light to moderate air I will ease it maybe up to 2"-but reaching and running in heavy air-leave it tight-you will go faster.

So, if you determine you need a fuller sail for conditions, upwind you can ease a bit of outhaul, and use just enough halyard/cunningham to keep the draft in the main JUST slightly fwd of midpoint (from luff to leech).
Downwind, ease a tiny bit more outhaul, then ease the cunningham all the way, and maybe a bit more halyard to "round up" the sail-but you don't want the halyard too low, because there is more wind at the top of the rig, and just like with the outhaul, you will begin to lose some projected area.

Anyway-great to see a boat like this being raced so aggresively!

Cheers,
S