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VMG answers
Thanks for the great ideas and here are some answers to questions that were raised . Wind gusts would be the type that go 12 to 20 for 6 seconds one time and then 12 to 20 for 6 minutes the next time. The rig: 2 ton, 8 m, high freeboard, internal ballast, centerboard, wide beam aft, fractional Bermuda rig sloop, no backstay, no traveler, 8/1 vang with boom kicker, already reefed.
Thanks for the great ideas and here are some answers to questions that were raised . Wind gusts would be the type that go 12 to 20 for 6 seconds one time and then 12 to 20 for 6 minutes the next time. The rig: 2 ton, 8 m, high freeboard, internal ballast, centerboard, wide beam aft, fractional Bermuda rig sloop, no backstay, no traveler, 8/1 vang with boom kicker, already reefed.
Hal, In your case
I would permanently ease off the boomvang a little to allow the boom to rise and twist off the main (but not slack it), ease the main sheet a little to twist off the mainsail to keep the boat on its feet without dumping the main, and play the initial puff by pinching slightly to both work work the boat a pinch to weather, and prevent breaking (slowing) with the rudder, then ease the jib sheet a pinch and foot off a little in the extended puffs to keep your boat speed up. When the puff passes re-trim to the original settings and come back to close hauled. I'm surprised you don't have a traveller or a backstay and you are at a disadvantage without them. Most fractional rigs require the backstay to adjust both the head-stay tension and the mast bend, to control the draft (power) of the jib and shape of the main. Without the backstay you are at a serious disadvantage, and without a traveler you lose many of the desired mainsail trim positions available.
I would permanently ease off the boomvang a little to allow the boom to rise and twist off the main (but not slack it), ease the main sheet a little to twist off the mainsail to keep the boat on its feet without dumping the main, and play the initial puff by pinching slightly to both work work the boat a pinch to weather, and prevent breaking (slowing) with the rudder, then ease the jib sheet a pinch and foot off a little in the extended puffs to keep your boat speed up. When the puff passes re-trim to the original settings and come back to close hauled. I'm surprised you don't have a traveller or a backstay and you are at a disadvantage without them. Most fractional rigs require the backstay to adjust both the head-stay tension and the mast bend, to control the draft (power) of the jib and shape of the main. Without the backstay you are at a serious disadvantage, and without a traveler you lose many of the desired mainsail trim positions available.
I wouldn't do it the way Joseph S. recommends.
That's a strategy just begging for a round-up. Instead, I'd keep the jib sheet tightly trimmed so that the headsail begins to pinch the moment weather helm builds. I'd keep the vang tight for the same reason: in heavy air twist in the leach just encourages a round-up. You want the sails flat and the sheets trimmed all the way. Traveler down. If you don't have a traveler, make it the next improvement. The goal with a centerboarder is to keep the boat as flat as possible. The more you heel the more leeway you make, which means lower VMG. Pinch during gusts as high as you can without appreciable drops in boat speed. The more it gusts, the less useful your telltales are going to be. Keep one eye on the knot log and the other on the cat's paws.
That's a strategy just begging for a round-up. Instead, I'd keep the jib sheet tightly trimmed so that the headsail begins to pinch the moment weather helm builds. I'd keep the vang tight for the same reason: in heavy air twist in the leach just encourages a round-up. You want the sails flat and the sheets trimmed all the way. Traveler down. If you don't have a traveler, make it the next improvement. The goal with a centerboarder is to keep the boat as flat as possible. The more you heel the more leeway you make, which means lower VMG. Pinch during gusts as high as you can without appreciable drops in boat speed. The more it gusts, the less useful your telltales are going to be. Keep one eye on the knot log and the other on the cat's paws.
Further comments of VMG optimization .....
When racing or just plain trying to save time when cruising, at the end of a long tack its usually best to radically pinch up at the end of a leg. True the boat speed will go down but the boat will go to weather better .... and the distance SAVED on the NEXT tack will be remarkable, sometimes you will gain MANY boat lengths on the next tack. Racing (or long distance sailing) is a game of 'inches' so any inches you can save on the 'next' tack will be rewarded by less distance to be travelled on the next leg. How to pinch (with some speed), .... simply over-tighten the main sheet so that the leech of the mainsail begins to 'hook to weather' (leech tell tales will begin 'go forward' on the leeward side) and let the boat 'lay over on its side' .... you are now using the curvature of the hull to help the boat to go to weather; but, becareful that you dont develop too much weather helm, if so bear down a bit to keep the speed up. Hooking the leech to weather is like 'dropping the flaps' on a wing: higher lift but more stable at slower speed. For most 'cruising' and especially for racing I usually 'hook up' for the last 5% of a leg .... to GAIN many boatlengths on the 'next' leg. With boat laid over on its beam, you're all set to do a 'roll tack' ....... but if you're not roll tacking dont forget to bring battens (especially the second batten from the top) back to 'parallel to the centerline' (or just a little to leeward) to help accelerate faster out of the tack. Due to 'trigonometry' following VMG at the 'end' of leg is inefficient, so this technique transfers overall boat speed -- to distance gained on the 'next' leg and is a 'killer' for gaining distance on the 'next' leg. So setting up for optimum VMG works best in the beginning of a leg but pinching up usually helps at near the end of a leg.
When racing or just plain trying to save time when cruising, at the end of a long tack its usually best to radically pinch up at the end of a leg. True the boat speed will go down but the boat will go to weather better .... and the distance SAVED on the NEXT tack will be remarkable, sometimes you will gain MANY boat lengths on the next tack. Racing (or long distance sailing) is a game of 'inches' so any inches you can save on the 'next' tack will be rewarded by less distance to be travelled on the next leg. How to pinch (with some speed), .... simply over-tighten the main sheet so that the leech of the mainsail begins to 'hook to weather' (leech tell tales will begin 'go forward' on the leeward side) and let the boat 'lay over on its side' .... you are now using the curvature of the hull to help the boat to go to weather; but, becareful that you dont develop too much weather helm, if so bear down a bit to keep the speed up. Hooking the leech to weather is like 'dropping the flaps' on a wing: higher lift but more stable at slower speed. For most 'cruising' and especially for racing I usually 'hook up' for the last 5% of a leg .... to GAIN many boatlengths on the 'next' leg. With boat laid over on its beam, you're all set to do a 'roll tack' ....... but if you're not roll tacking dont forget to bring battens (especially the second batten from the top) back to 'parallel to the centerline' (or just a little to leeward) to help accelerate faster out of the tack. Due to 'trigonometry' following VMG at the 'end' of leg is inefficient, so this technique transfers overall boat speed -- to distance gained on the 'next' leg and is a 'killer' for gaining distance on the 'next' leg. So setting up for optimum VMG works best in the beginning of a leg but pinching up usually helps at near the end of a leg.
I need to make a correction
I said: Additionally, as you sail in waves, your mast forms a fore and aft pendulum. When you go up the wave your mast swings back and the apparent wind goes aft and when you go over the top and go down the back side of the wave the mast swings forward and the apparent wind goes forward. With no twist in the main, the main goes from stalled as the mast swings aft, to luffing as the mast goes forward, and the main never develops a correct trim. This produces a loss of power in the main. With a twist in the main, the drive is higher when the mast comes back and it moves steadily and uniformly down the sail as the mast goes forward. So some part of the main is always driving. I got my apparent wind discussions backwards. Thats what happens when you get older I haven't Taught sailing in many years) What I should have said is: Additionally, as you sail in waves, your mast forms a fore and aft pendulum. When you go up the wave your mast swings back and the apparent wind goes forward and when you go over the top and go down the back side of the wave the mast swings forward and the apparent wind goes aft. With no twist in the main, the main goes from stalled as the mast swings forward, to luffing as the mast goes aft, and the main never develops a correct trim. This produces a loss of power in the main. With a twist in the main, the drive is lower when the mast comes back and it moves steadily and uniformly up the sail as the mast goes forward. So some part of the main is always driving. Sorry about that-- remember that we are not talking about a huge amount of twist And consequently in the picture the lower part of the main is driving. Sometimes my mind and my typing are not on the same page. Sorry again I just hate to make mistakes.
I said: Additionally, as you sail in waves, your mast forms a fore and aft pendulum. When you go up the wave your mast swings back and the apparent wind goes aft and when you go over the top and go down the back side of the wave the mast swings forward and the apparent wind goes forward. With no twist in the main, the main goes from stalled as the mast swings aft, to luffing as the mast goes forward, and the main never develops a correct trim. This produces a loss of power in the main. With a twist in the main, the drive is higher when the mast comes back and it moves steadily and uniformly down the sail as the mast goes forward. So some part of the main is always driving. I got my apparent wind discussions backwards. Thats what happens when you get older I haven't Taught sailing in many years) What I should have said is: Additionally, as you sail in waves, your mast forms a fore and aft pendulum. When you go up the wave your mast swings back and the apparent wind goes forward and when you go over the top and go down the back side of the wave the mast swings forward and the apparent wind goes aft. With no twist in the main, the main goes from stalled as the mast swings forward, to luffing as the mast goes aft, and the main never develops a correct trim. This produces a loss of power in the main. With a twist in the main, the drive is lower when the mast comes back and it moves steadily and uniformly up the sail as the mast goes forward. So some part of the main is always driving. Sorry about that-- remember that we are not talking about a huge amount of twist And consequently in the picture the lower part of the main is driving. Sometimes my mind and my typing are not on the same page. Sorry again I just hate to make mistakes.
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