Questions yet unanswered on heeling

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Richard Novak

Not having experienced excessive healing, I ask: 1) will heeling 35-40 degrees on a 1991 Hunter 35.5 put "dangerous" stress to the rigging, or not necessarily so? 2) To control excessive heeling, would you move out the traveler first, or open the main? 3) If I open the main, I run into the problem of the main hitting the fractional spreaders. How long before I chafe the sail?
 
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Tony Kriz

Some thoughts...

While I can't speak to the issue of stress on the rigging I would think you would suffer a loss of performance more than anything. I'd ease out the traveler before you let out the main. I've got the same problem with the spreaders on my 320 if you let out the main too much.
 
Sep 24, 1999
1,511
Hunter H46LE Sausalito
heeling

The more you heel, the less your sails are able to capture the wind's energy. Think of heeling as the rig's effort to depower itself. The wind hitting a sail at 45% tends to roll of the top, converting far less energy into forward motion than the wind hitting a sail at 15% heel. Rather than letting the mainsheet go, use the helm to pinch the boat to windward in a gust. That way you maintain control. If you have to do this often, you're not reefing early enough. ... In response to question #2, moving the traveler to leeward does in effect "open" the main, but what you're really looking for is to keep the leech of the main open. Don't just think in terms of angle, shape is also important.
 
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Bob Rutland

Why ?

Why would you want to heel 35 to 40 degrees? It not only stresses the rigging,rudder, and not to mention the crew, but it is a very inefficient way to sail. A flat boat is a fast boat. I'm not a natical engeneer, but I doubt this much heel would be dangerous to rigging that is in good shape. If you have the traveler eased and the main out to the spreaders, it's probably time to reef.
 
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J. Baker

Why not???

Heeling creates side G forces and G's are associated with fun stuff. They also make you feel like the boat is going faster and our H-34 does not slow down during a puff that knocks us over. Most of my crew likes 15 to 30 degrees and boat speed is really good at those angles. 30 to 40 is OK occasionally!! We don't usually reef unless we are getting rounded up!! If we are unbalanced and fighting the weather with the rudder, speed suffers. Have fun!!!!!!!!!!
 
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Tim McCarty

Bury the Rail!!

Everyone wants to sail their boat like an S2, and though I understand that burying the rail and hanging over the side for ballast are fun, they aren't much use for a cruiser like me. I am much more concerned with optimal sail shape and maximizing wind speed. I usually will try to heel no more than 15 degrees. Fractional rigged boats are a challenge sometimes in strong winds because the swept-back spreaders do tend to hinder sail shape when you really need to let out the main. These are all good questions and answers. I am interested in more comments on the subject.
 
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Jay Eaton

Speed??

Oh yes, heeling is fun. Next time as your boat heels over past 15-20 degrees, watch your speedo for its reaction. For most sailboats, beyond a certain point more heel means less speed. It's a trade off.
 
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Jim Kolstoe

Heeling for fun and . . .

The thing about heeling is that its unavoidable. Therefore, most sailboats are designed to be more efficent with some heel. Too much heel does slow you down, but unless you're racing or cruising/voyaging, who cares. ITS FUN AND EXCITING to feel the your boat heel over with the power of the wind. Does it put more stress on the hull and rigging? I suppose so, since you are using the lateral forces on your sail to pick up your keel. But I also presume that any boat in commercial production is designed to withstand such predicatable forces. About your concerns of excess wear to your main from the swept back spreaders. Put patchs on them. They are available as adhesive patches of dacron sail fabric. Avoid exactly ovelaping them to avoid creating a hinge point that will wear out quicker. Mine have protected my main from any damage, dispite years of use. Jim Kolstoe, h23 Kara's Boo
 
Jun 5, 1997
659
Coleman scanoe Irwin (ID)
Heeling for profit ???

Are most sailboats really designed to be more efficient when heeled a bit, as Jim argues? I have often heard that said but always find it odd that architects that care about speed would not design hull shape to be most speed efficient when it really counts, i.e. when there is very little wind (and consequently, little or no heel). Furthermore, if this were true, why would there not be an optimum degree of heel specified for a given hull shape and would racers try to use their ballast to maintain that angle of heel rather than to keep the boat flat? This does not preclude that some boats may, in fact, become more efficient when heeled. After all, nautical architects are only human too and all sailboat designs are compromises of one sort or another. Richard's first question (stresses) has been answered by several responders. I like Jim's image of the pressure on the sails picking up the weight of the keel. In other words, the vessel is being balanced over an imaginary fulcrum. Now imagine a big wave coming along and suddenly lifting that fulcrum! Isn't that how one would try to break a tall object over one's knee? So, yes, the design should be able to withstand the forces of the wind. However, what happens in heavy seas is a different issue altogether. IMHO, the answers to Richard's second question do not emphasize strongly enough that the first line of defense is to flatten the sails and introduce more twist. If properly done (i.e. by stretching both luff and foot, opening the leech and increasing mast bend when possible) the effect on fairly new, well-designed sails can be dramatic. Both heading up (i.e. pointing the vessel closer to the wind) or letting the traveler or mainsheet out (i.e. only pointing the boom closer to the wind) are appropriate temporary reactions to gusts as they both reoptimize the angle of attack to the apparent wind angle during the gust (or might perhaps even overcorrect in order to depower the sail a bit by "pinching"). I tend to agree with John that it is easier to head up, and perhaps even "pinch", rather than to drop the traveler. After all, the helmsperson (or the windvane)is already on station. Moreover, dropping the traveler does not yet correct the angle of attack for the genoa or staysail. However, to keep sailing around with a less than optimum angle of attack for a long time (rather than to reef) in order to depower the sails is to ask for a poorly balanced vessel. Those of us with windvane steering soon learn to avoid that. Finally, it pays to be aware of the effects of excessive heel on: (1) effective displacement (the wind vectors pressing the sails down may well add hundreds of pounds to the effective displacement of the vessel; sort of inviting a couple of heavy passengers along for the ride); (2) keel efficiency (unless you do have a canting keel you will start to lose pointing ability by sideslipping, whereas loss of valuable "keel lift" will further reduce speed); and (3) rudder efficiency (larger rudder angles will be needed, thereby increasing drag; moreover, some rudder designs will become less well balanced, thereby overpowering the helmsperson or the windvane). Can heeling be fun? Of course it can !!! Therein, however, lies pretty much its sole profit.... Flying Dutchman
 
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Ed

Too much heeling causes...

Additional stress on the windward shrouds, and it causes the boat to move leeward since the keel isn't as deep as it is when the boat is sailing closer to perpendicular to the wind. As a result it isn't able to counteract the greater sideways force sufficiently. In other words, the actual course heading will be much further downwind than you intended. This is particularly important when trying to claw away from a lee shore. ~ Happy sails to you ~ _/) ~
 
Sep 24, 1999
1,511
Hunter H46LE Sausalito
heel efficiency

Henk brings up the interesting point of whether a hull is more efficient when heeled than when sailing flat. The reason for this is that the effective waterline actually increases on a boat that heels at its optimum angle. The beamier the boat, the more this is the case. This is precisely why, in light air situations, the call for "leeward weight" goes out on racing boats. But at the point where you're burying the rail, efficiency is being sacrificed to increased leeway and the increased rudder drag due to fighting weather helm. What the rail-buryers tend not to realize is that even though their speed through the water may have gone up, their velocity made good has gone down. When a sailboat going to weather heels beyond 20 degrees its keel is no longer provides effective lateral resistance, which means you're going sideways(leeway)as well as going forward. That's why the guy who reefs first so often arrives first. For some of us, it's the arriving first that provides the most fun.
 
Jun 5, 1997
659
Coleman scanoe Irwin (ID)
John, I agree that waterline length increases

for most of the vessels on this board; i.e. those with substantial overhangs. However, my understanding is that increased waterline length only matters in light winds if boat speed is high enough to get into the wave-drag dominated part of the drag vs. speed curve; i.e. at approx. 2/3 of hull speed. Below that speed additional wetted area only causes more parasitic drag and might actually slow a vessel down further. IMHO, one of the reasons some racing skippers induce heel by ordering the crew to the lee side in very light winds is to reduce the tendency of sails and boom to slat, e.g. when hitting a small wave, as that tends to kill whatever boat speed is left. Flying Dutchman
 
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Richard Novak

John, Henk, what about this?

Guys, I like your suggestion about pinching. Once I had to do that 'cause I had no other alternative and it worked. However, pinching works well when you are pointing and you have 10-15 degrees to work with, if the wind is that strong. But what do you do when you are in a narrow channel on a beam reach? To pinch, you would have to round up 50-60 degrees and doing so would take the boat into shoals. What then? thanks
 
Jun 5, 1997
659
Coleman scanoe Irwin (ID)
In a narrow channel with gusty winds,

you not only have to control your own vessel but also need to stay out of the way of others. Under those special conditions I would not be ashamed at all to drop all sail and go on the engine or outboard if I did not feel 100% comfortable about the situation. Alternatively, when on a beam reach in a narrow channel, I might consider putting a pretty large reef in the main and sailing mostly on our roller-furled staysail or jib. After all, I assume that we are not trying to win races there. However, If I would feel comfortable enough about dealing with sudden, overpowering wind gusts or squalls (while severely restricted in manoevering ability) I might decide to keep sailing on after first carefully depowering the main by flattening or reefing and introducing twist, if necessary. If necessary, I can then still let the traveler out, release the mainsheet plus boomvang, or -- in an emergency -- let the main halyard go altogether. The least of my worries in emergency situations is whether the main will touch the spreaders for a few minutes or not. Meanwhile, in a narrow, busy channel under squally or gusty conditions, I would consider it not un-seamanlike to keep the engine or outboard running on standby in order to avoid losing helm control. Flying Dutchman
 
Sep 24, 1999
1,511
Hunter H46LE Sausalito
pinching

When you ease the mainsheet traveler to leeward, you are in effect pinching the main. When you pinch the main only, leaving the jib in place, you relieve weather helm. This is a common solution on race boats that are ill-equipped to reef. A better solution for cruising boats is to reef. Regardless, my first impulse when overpowered going to weather is to pinch, because this will increase my VMG in most cases.
 
Sep 24, 1999
1,511
Hunter H46LE Sausalito
Reply to Henk

Your point about parasitic drag is well taken. I would agree that the leeward-weight strategy depends a great deal upon hull design. Another factor would be displacement/weight ratio. My own experience is that leeward weight is much more effective in ultra-light (ULDB) boats I've campaigned, such as the Olson 30, than in more moderate displacement boats, such as the Express 37. One of the trade-offs here is that the breeze is generally stronger, in light winds, the further from the water, which in terms of sail trim means that attending to the top half of the sail, especially in high-aspect rigs with ample roach, is important. On many boats this means there's a benefit to keeping the boat flat if for no other reason that you're keeping the sail head higher. That said, I must confess that I don't know where the tradeoff lies in terms of the wave-drag dominated part of the drag vrs. speed curve. My guess is that, on a boat-to-boat basis, I'd tend to answer that question more by the feel of the helm than anything else, with the understanding that the lighter the displacement and/or the greater the overhang, the more I'd tend to induce heel in light air. And twist. The very BEST light-air strategy, of course, is to put on some Vivaldi and crank up the stereo. I find this much more effective than turning on the engine.
 
Dec 2, 2003
4,245
- - Seabeck WA
Wow, you guys are good! This thread is turning

into a text book. But about stress on rigging wire/rod, I recall a boat design rule that specifies the strength of the shrouds. It seems to me that each one should hold up twice the weight of the boat. The 'rule' insures strength to hold up the rig in extreme cases.
 
Jun 5, 1997
659
Coleman scanoe Irwin (ID)
John's remarks about advantages of modest heel

for lighter vessels prompted me to do some research. I found out that -- in agreement with John's remarks but counter to my own intuition -- the wetted area of some hull shapes is markedly reduced at modest angles of heel! A pronounced example is provided by a Laser hull (see link). Note that the wetted area reduction is calculated under static conditions i.e. not taking any planing tendencies into account. So, by simply heeling this hull one can reduce parasitic drag. This brings up the interesting question whether ,for some hull shapes, induced heel could perhaps even be helpful on a DDW course under spinnaker.... ;o) Have fun! Flying Dutchman
 
Jun 5, 1997
659
Coleman scanoe Irwin (ID)
Required shroud strength

Fred, your question about "required shroud strength" would appear to have no simple answer because of the complexity of the many possible underlying factors involved if and when a shroud happens to fail underway. Yet, from first principles, I do agree that the strength of the rig might be compromised when sailing at extreme heel. As stated in my earlier post: "I like Jim's image of the pressure on the sails picking up the weight of the keel. In other words, the vessel is being balanced over an imaginary fulcrum. Now imagine a big wave coming along and suddenly lifting that fulcrum! Isn't that how one would try to break a tall object over one's knee?" Fortunately, at least one helpful generalization can be made when trying to reduce the statistical probability that any piece of hardware on board might break, namely: if that failure is a high probability event one should replace the piece with a much stronger one whereas if it is a low probability event one should try to back up the function of that shroud, block, bracket, etc. In order to illustrate this principle with a practical example I need to make 2 simplifying assumptions: (1) in the real world one is highly unlikely to ever gain more than a factor of ten in strength by replacing a low quality piece of hardware by a high quality one; and (2) the statistical probability of the back-up piece failing is independent of that of the original one. Now imagine that you estimate the probability of your genoa forestay breaking on a particular ocean passage to be 1 in 30 and that you want to improve those odds by installing the strongest and most expensive forestay you can afford. According to the above rules the most optimistic expectation is now that your chances have become 10 times better, i.e. 1 in 300. By contrast, installing an inner stay of the same quality could have reduced the chance of failure to 1 in 900 (30x30).... If, pn the other hand, you estimated your forestay to have a probability of 1 in 3 to break on that same trip you would be better off to replace it with a 10 times stronger stay (if available) than to back it up with a second stay of the same low quality. Have fun! Flying Dutchman
 
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