Let's see if I have this straight... Powering up the jib decreases weather helm by moving the center of effort forward. Powering up the jib increases weather helm by increasing heeling. We can reduce weather helm by depowering the main by sheeting it in, thus flattening it. We can reduce weather helm by easing the sheet, thus twisting it an spilling air on top (thus reducing both power and heeling moment). Which is correct? a) all of the above, of b) none of the above. c) some of the above I don't mean to sound sarcastic. I'm getting more confused the more I (a novice) learn about this issue. It seems a bit to me that the effect of opposite actions are the same, or maybe, the results are unpredictable, as these actions may cancel out each other. Can anyone help to explain this apparant contradiction? Many thanks! George Kornreich
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think balance
it is confusing, yes, but hang in there. it might help to remember that there are two planes that need to be balanced. the center of effort, which is in your sails, needs to balance with the center of lateral resistance, which is in your keel. think of this first plane as being in terms of fore/aft allignment. if this alignment is not balanced, some but not all points of sail will be affected. a foreward center of effort will tend to effect you more downwind (as in broaching), and an aft center of effort will tend to effect your control more upwind (rounding up). Where it gets confusing is that the center of effort also needs to balance with the center of drag, which is also below the waterline. Think of this as balancing the boat abeam. if you had x-ray vision and could look down on a heeled sailboat from above (a god's eye view?) you would see the center of effort and the center of drag to be offline, moreso the more the boat is heeled. if, for example, the boat is on port tack, the center of drag will be to port and the center of effort will be to starboard of a theoretical balance point. this will cause the boat to want to turn to weather. we call this phenomenon "weather helm." easier to fix than to understand, because all you have to do is reef your sails so that they balance. most fraction-rigged sloops are balanced by reefing the main first, while most masthead-rigged sloops are balanced by switching to a smaller headsail first. at some point (winds about 20 knots true, depending on the tenderness of the boat) both sails will need to be adjusted. cutters and ketches, of course, have split rigs that make them easier to balance. the neat thing about all this on the new fraction-rigged hunters, such as my 410, is that when you reef/balance them in strong winds, they end up going faster. i routinely take BUOYANT out in 25+ knot winds here in San Francisco Bay without experiencing any weather helm at all. part of this is because my wife has 358 pairs of shoes onboard, which gives us an extremely low center of gravity. (Think of that as the third plane of balance, if you really want to understand your boat.)
it is confusing, yes, but hang in there. it might help to remember that there are two planes that need to be balanced. the center of effort, which is in your sails, needs to balance with the center of lateral resistance, which is in your keel. think of this first plane as being in terms of fore/aft allignment. if this alignment is not balanced, some but not all points of sail will be affected. a foreward center of effort will tend to effect you more downwind (as in broaching), and an aft center of effort will tend to effect your control more upwind (rounding up). Where it gets confusing is that the center of effort also needs to balance with the center of drag, which is also below the waterline. Think of this as balancing the boat abeam. if you had x-ray vision and could look down on a heeled sailboat from above (a god's eye view?) you would see the center of effort and the center of drag to be offline, moreso the more the boat is heeled. if, for example, the boat is on port tack, the center of drag will be to port and the center of effort will be to starboard of a theoretical balance point. this will cause the boat to want to turn to weather. we call this phenomenon "weather helm." easier to fix than to understand, because all you have to do is reef your sails so that they balance. most fraction-rigged sloops are balanced by reefing the main first, while most masthead-rigged sloops are balanced by switching to a smaller headsail first. at some point (winds about 20 knots true, depending on the tenderness of the boat) both sails will need to be adjusted. cutters and ketches, of course, have split rigs that make them easier to balance. the neat thing about all this on the new fraction-rigged hunters, such as my 410, is that when you reef/balance them in strong winds, they end up going faster. i routinely take BUOYANT out in 25+ knot winds here in San Francisco Bay without experiencing any weather helm at all. part of this is because my wife has 358 pairs of shoes onboard, which gives us an extremely low center of gravity. (Think of that as the third plane of balance, if you really want to understand your boat.)
Sort of.
I have to make this quick but.... As far as the mainsail... You can flatten the main with mainsheet or vang, outhaul, and halyard. This depowers the main and moves the CE forward. Both reduce heeling and increase forward lift (that's good). You can also if needed drop the traveller. The main remains flat in this case. The traveller doesn't affect the "flatness" of the main. So in this case do both. Flatten first, then drop the traveller if necessary. Jib... I seem to be in the minority on this. Powering up the jib to reduce weather helm still doesn't work for me. What you are doing is encouraging the lift component of the jib that creates heeling. Yes this reduces weather helm, but it doesn't increase speed. Encouraging the boat to heel is not a speed enhancer. On the other hand if you move the jib cars aft. The lower part of sail is flatter. The draft of sail moves forward. In this case the lift component that promotes heeling is reduced, while the lift component that creates forward motion increases. The top of the jib also twists off with the cars aft. In this case you are minimizing the lift from the top of the sail. Effectively you are depowering the jib, but what you are taking away is the top part of sail that is creating the most amount of heeling for its contribution to forward motion. It's that lever arm thing. Since the top of the jib is further away from the center of rotation it has more leverage and creates more heeling. Same reason you reef the top of your main and not the bottom. Gotta go. Hope this helps. Feel free to disagree and make yours points!!!
I have to make this quick but.... As far as the mainsail... You can flatten the main with mainsheet or vang, outhaul, and halyard. This depowers the main and moves the CE forward. Both reduce heeling and increase forward lift (that's good). You can also if needed drop the traveller. The main remains flat in this case. The traveller doesn't affect the "flatness" of the main. So in this case do both. Flatten first, then drop the traveller if necessary. Jib... I seem to be in the minority on this. Powering up the jib to reduce weather helm still doesn't work for me. What you are doing is encouraging the lift component of the jib that creates heeling. Yes this reduces weather helm, but it doesn't increase speed. Encouraging the boat to heel is not a speed enhancer. On the other hand if you move the jib cars aft. The lower part of sail is flatter. The draft of sail moves forward. In this case the lift component that promotes heeling is reduced, while the lift component that creates forward motion increases. The top of the jib also twists off with the cars aft. In this case you are minimizing the lift from the top of the sail. Effectively you are depowering the jib, but what you are taking away is the top part of sail that is creating the most amount of heeling for its contribution to forward motion. It's that lever arm thing. Since the top of the jib is further away from the center of rotation it has more leverage and creates more heeling. Same reason you reef the top of your main and not the bottom. Gotta go. Hope this helps. Feel free to disagree and make yours points!!!
Main sail twist
It seems most posts are saying to use the boomvang to depower the mainsail, in my sailing experiance using the vang helps to adjust the main shape off the wind (takes the place of the mainsheet pulling down on the boom,as when going upwind)using the vang upwind will not let the upper leach of the main to twist off and reduce power. Although the B&R rigs does a good job of not letting us ease out our sails to depower, but using the vang will keep the main off the rigging and getting our sails dirty. Depower both sails by letting the tops luff. Move jib sheet leads aft and ease the mainsheet. keep the center of effort low. And don't be chicken to reef, after reefing you have the same sail area as most other boats with full sail!!
It seems most posts are saying to use the boomvang to depower the mainsail, in my sailing experiance using the vang helps to adjust the main shape off the wind (takes the place of the mainsheet pulling down on the boom,as when going upwind)using the vang upwind will not let the upper leach of the main to twist off and reduce power. Although the B&R rigs does a good job of not letting us ease out our sails to depower, but using the vang will keep the main off the rigging and getting our sails dirty. Depower both sails by letting the tops luff. Move jib sheet leads aft and ease the mainsheet. keep the center of effort low. And don't be chicken to reef, after reefing you have the same sail area as most other boats with full sail!!
some answers
Weatherhelm normally seen in tall rigs comes mainly from a raked mast if you use your mainsail halyard on a no wind day, connect a jug (gallon) on water to the end and use the line and jug as a plumb bob, standing still by the boom, you can tell if the mast is raked, if the jug is not resting on the mast just above the goose neck, you've got a raked mast. make it straight, or eleaviate the condition with a flattening reef, which is approx. 11/2' to 21/2' above the boom, if you have a multi block sheeting sys. on the boom, add a 4 to 1 boom vang, if you don't have a flattening reef reef it to the first reef point, it has been suggested by some ole salty sailors to install a long narrow strip of lead, then sheathed in lead sheet around the foward lower edge of your rudder, but you're the first that I've heard of that's blames it on the head sail, the professionals say by moving the mast foward about 6' to a foot will also eliminate the weatherhelm to some degree, you need a little weatherhelm, but try the removal of the rake and or see if your mainsail has a flattening reef, or try sailing under a reef pt.
Weatherhelm normally seen in tall rigs comes mainly from a raked mast if you use your mainsail halyard on a no wind day, connect a jug (gallon) on water to the end and use the line and jug as a plumb bob, standing still by the boom, you can tell if the mast is raked, if the jug is not resting on the mast just above the goose neck, you've got a raked mast. make it straight, or eleaviate the condition with a flattening reef, which is approx. 11/2' to 21/2' above the boom, if you have a multi block sheeting sys. on the boom, add a 4 to 1 boom vang, if you don't have a flattening reef reef it to the first reef point, it has been suggested by some ole salty sailors to install a long narrow strip of lead, then sheathed in lead sheet around the foward lower edge of your rudder, but you're the first that I've heard of that's blames it on the head sail, the professionals say by moving the mast foward about 6' to a foot will also eliminate the weatherhelm to some degree, you need a little weatherhelm, but try the removal of the rake and or see if your mainsail has a flattening reef, or try sailing under a reef pt.
Depowering the mainh
George, I have been reading the weather helm posts and there seems to be a split of opnion as to whether to power or depower the jib. My guess is its one of those things that depends on the boat and conditions. My 35 Legend is, like yours I believe, fractionally rigged (the forestay only goes up about 3/4 of the mast) and thus has a "built in" reef. Mine also has the original 110 jib, which is not a very big sail. Therefore the jib does not induce a lot of heeling force but does counteract weath helm. On the other hand, a boat with a topmast rigged forestay and a 150 genny will generate a lot more heal (which creates whether helm) and I could see the need to depower it or reef it, depending on the situation and how high you are trying to point. Everyone seems to agree that depowering the main reduces weather helm. However, sheeting in does not depower the main; to the contrary you want to sheet ou a little bit. When people speak of flattening the main they do not mean making it flatter against the wind but taking the arc or fullness out of the sail. Generally speaking, a flatter sail (with less curve) will be less powerful that a fuller sail with more curve, because the wing effect of the sail. The power of a sail on a reach comes from wind traveling farther on the lee side than on the weather side -- the same thing that creates life on an airplane wing. That is why a sailboat goes faster on a reach than on a run. A fuller sail creates a greater arc which increases the speed differential between the weather and lee sides of the sail, which increases the sail's power on a reach. The opposite is also true. As another post mentioned, you flatten the sail by tightening the main halyard (or cunningham if you have one), and the outhaul. Sheeting the main will flatten the sail by pulling the boom down, but (assuming your traveler is centered) will also pull the sail to the center of the boat. Unless you need to do that because you are close hauled, the main effect will be that the wind push the the boat over, and both the heal and the aft of center push on the boat will create weather helm. The boom vang will pull the boom down without pulling the sail to center. Pulling the boom down by either sheeting the main or tightening the vang flattens the leach of the main whereas the main halyard and outhaul flattens the arc in the middle of the sail. When the mainsheet (or vang) is eased, the leach curves, and while the sail is not "flatter," a curved leach allows air to spill out of the weather side of the sail, which depowers it by reducing the difference in wind speed on both sides of the sail. Now, if you are on a broad reach in a strong wind, simply easing the main will loosen the leach too much, causing your leach to flap around and your boom to bounch. So on a broad reach, you want to let the traveler out, use the vang to keep the boom down enough for a good shape, and let the mainsheet out enough to spill a little wind to the extent necessary to balance your helm.
George, I have been reading the weather helm posts and there seems to be a split of opnion as to whether to power or depower the jib. My guess is its one of those things that depends on the boat and conditions. My 35 Legend is, like yours I believe, fractionally rigged (the forestay only goes up about 3/4 of the mast) and thus has a "built in" reef. Mine also has the original 110 jib, which is not a very big sail. Therefore the jib does not induce a lot of heeling force but does counteract weath helm. On the other hand, a boat with a topmast rigged forestay and a 150 genny will generate a lot more heal (which creates whether helm) and I could see the need to depower it or reef it, depending on the situation and how high you are trying to point. Everyone seems to agree that depowering the main reduces weather helm. However, sheeting in does not depower the main; to the contrary you want to sheet ou a little bit. When people speak of flattening the main they do not mean making it flatter against the wind but taking the arc or fullness out of the sail. Generally speaking, a flatter sail (with less curve) will be less powerful that a fuller sail with more curve, because the wing effect of the sail. The power of a sail on a reach comes from wind traveling farther on the lee side than on the weather side -- the same thing that creates life on an airplane wing. That is why a sailboat goes faster on a reach than on a run. A fuller sail creates a greater arc which increases the speed differential between the weather and lee sides of the sail, which increases the sail's power on a reach. The opposite is also true. As another post mentioned, you flatten the sail by tightening the main halyard (or cunningham if you have one), and the outhaul. Sheeting the main will flatten the sail by pulling the boom down, but (assuming your traveler is centered) will also pull the sail to the center of the boat. Unless you need to do that because you are close hauled, the main effect will be that the wind push the the boat over, and both the heal and the aft of center push on the boat will create weather helm. The boom vang will pull the boom down without pulling the sail to center. Pulling the boom down by either sheeting the main or tightening the vang flattens the leach of the main whereas the main halyard and outhaul flattens the arc in the middle of the sail. When the mainsheet (or vang) is eased, the leach curves, and while the sail is not "flatter," a curved leach allows air to spill out of the weather side of the sail, which depowers it by reducing the difference in wind speed on both sides of the sail. Now, if you are on a broad reach in a strong wind, simply easing the main will loosen the leach too much, causing your leach to flap around and your boom to bounch. So on a broad reach, you want to let the traveler out, use the vang to keep the boom down enough for a good shape, and let the mainsheet out enough to spill a little wind to the extent necessary to balance your helm.
remember
That "excessive weather helm" may be your boat trying to tell you that its overpowered and you should reef. The tall rig/ large mainsail fractional rigs on the newer Hunters are designed to use more drive from the main (hence the 110% headsail) and this means you should reef the main first and probably earlier than on a masthead rig. Using the vang to flatten the mainsail is OK, letting out the traveler is OK too, but if your'e still overpowered, comes a point when you NEED TO REEF!
That "excessive weather helm" may be your boat trying to tell you that its overpowered and you should reef. The tall rig/ large mainsail fractional rigs on the newer Hunters are designed to use more drive from the main (hence the 110% headsail) and this means you should reef the main first and probably earlier than on a masthead rig. Using the vang to flatten the mainsail is OK, letting out the traveler is OK too, but if your'e still overpowered, comes a point when you NEED TO REEF!
Thanks for sharing, Bryan.
To one, all to you Bryan, I continue to appreciate the valuable lessons and experienced advice I receive from reading the posts of knowledgable sailors on HOW. Another lesson has been printed and saved in my on-board library. Thank you for sharing your expenience. with us less knowledable, but willing sailors. Wynn Ferrel S/V Tranquility
To one, all to you Bryan, I continue to appreciate the valuable lessons and experienced advice I receive from reading the posts of knowledgable sailors on HOW. Another lesson has been printed and saved in my on-board library. Thank you for sharing your expenience. with us less knowledable, but willing sailors. Wynn Ferrel S/V Tranquility
Common Sense Response
My first instruction when learning to sail a dinghy was when in trouble, let go of everything. Translation- if the weather helm is strong and you leave the shets and rudder in the same position, you will heel to whatever angle the wind will take you. Corecting this can be a combination of rudder position(Let go and you will round into the wind, let the sheets out on the main and or headsail which will reduce the weather helm and degree of heel. No need to get hung up in the center of effort, blah, blah, blah. The judgment call comes in when deciding whether it is best to do the above or to reduce the sail surface area by reefing
My first instruction when learning to sail a dinghy was when in trouble, let go of everything. Translation- if the weather helm is strong and you leave the shets and rudder in the same position, you will heel to whatever angle the wind will take you. Corecting this can be a combination of rudder position(Let go and you will round into the wind, let the sheets out on the main and or headsail which will reduce the weather helm and degree of heel. No need to get hung up in the center of effort, blah, blah, blah. The judgment call comes in when deciding whether it is best to do the above or to reduce the sail surface area by reefing
LITTLE TRICK
Just a neat little trick that I learned for us that have roller furl on the head sail. When rolling in the head sail for reduicing sail area without getting a huge pocket that is almost impossible to flatten out I found that a piece of foam pipe insulation the closed cell kind, that by shoving it into the luft of the sail as I wind up the roller furl that the extra bulk it creates when rolled in I can get a much better sail shape at the "pocket" of the sail.This really helps to flatten the sail putting the load across the entire reduiced sail plan.
Just a neat little trick that I learned for us that have roller furl on the head sail. When rolling in the head sail for reduicing sail area without getting a huge pocket that is almost impossible to flatten out I found that a piece of foam pipe insulation the closed cell kind, that by shoving it into the luft of the sail as I wind up the roller furl that the extra bulk it creates when rolled in I can get a much better sail shape at the "pocket" of the sail.This really helps to flatten the sail putting the load across the entire reduiced sail plan.
Weather helm without heeling
In this thread about weather helm most attention has focussed on weather helm induced by heeling (most often induced by overpowered sails) while perhaps too little attention has been paid to weather helm without heeling. In order to avoid creating the mistaken notion among some of the beginning sailors in this group that the kneejerk response to weather helm problems should be to "flatten the main", "let go of the sheets", "move the jib leads aft", "reef early" or other measures primarily aimed at reducing heel, let me make the following two statements : (1) a little weather helm (e.g. corresponding to a 5-8 degree deviation of the rudder blade from the centerline) is generally considered desirable as it helps the helmsman (or the autopilot) steer a straighter course, thereby making up for the increased water resistance of the rudder blade; (2) reducing the heel to zero (e.g. by using ballast) will not solve weather helm problems caused by poorly balanced sail plans, excessive mast rake, mast placement too far aft (e.g. during attempted cutter conversions), fin keel placed too far forward or carrying too much weight in the aft section (squatting). With regard to the second point, I would like to note that most Hunter owners are unlikely to make drastic changes in keel design and/or mast placement. However, most cruisers (myself included) tend to accumulate tons of heavy gadgetry, accessories, materials and supplies over the years and stow this in the large cockpit and transom lockers. Also, many of us try to keep weight out of the bows in order to reduce pitching and to keep a drier foredeck. The net effect is a backwards rotation (squatting) of the entire vessel when seen from the side (note that this is not the same as mast rake). This rotation moves the center of (wind) effort aft while tending to bring the center of lateral (water) resistance forward (depending on the design of the hull and underwater appendages)). The squatting effect can be exacerbated by strong propellor thrust, which tends to make the bows lift further, e.g. during motorsailing. If you do have a bothersome weather helm problem, even when not heeling, examine your waterline (while sailing) and see if you are squatting excessively. If so, try to get rid of all the accumulated dead weight in the aft section and you may be surprised at the improved behavior of your helm. Flying Dutchman
In this thread about weather helm most attention has focussed on weather helm induced by heeling (most often induced by overpowered sails) while perhaps too little attention has been paid to weather helm without heeling. In order to avoid creating the mistaken notion among some of the beginning sailors in this group that the kneejerk response to weather helm problems should be to "flatten the main", "let go of the sheets", "move the jib leads aft", "reef early" or other measures primarily aimed at reducing heel, let me make the following two statements : (1) a little weather helm (e.g. corresponding to a 5-8 degree deviation of the rudder blade from the centerline) is generally considered desirable as it helps the helmsman (or the autopilot) steer a straighter course, thereby making up for the increased water resistance of the rudder blade; (2) reducing the heel to zero (e.g. by using ballast) will not solve weather helm problems caused by poorly balanced sail plans, excessive mast rake, mast placement too far aft (e.g. during attempted cutter conversions), fin keel placed too far forward or carrying too much weight in the aft section (squatting). With regard to the second point, I would like to note that most Hunter owners are unlikely to make drastic changes in keel design and/or mast placement. However, most cruisers (myself included) tend to accumulate tons of heavy gadgetry, accessories, materials and supplies over the years and stow this in the large cockpit and transom lockers. Also, many of us try to keep weight out of the bows in order to reduce pitching and to keep a drier foredeck. The net effect is a backwards rotation (squatting) of the entire vessel when seen from the side (note that this is not the same as mast rake). This rotation moves the center of (wind) effort aft while tending to bring the center of lateral (water) resistance forward (depending on the design of the hull and underwater appendages)). The squatting effect can be exacerbated by strong propellor thrust, which tends to make the bows lift further, e.g. during motorsailing. If you do have a bothersome weather helm problem, even when not heeling, examine your waterline (while sailing) and see if you are squatting excessively. If so, try to get rid of all the accumulated dead weight in the aft section and you may be surprised at the improved behavior of your helm. Flying Dutchman
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