Asymmetric Spinaker questions

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Bob F

I'm new to using a Asymmetric spinnaker (or any spinnaker). I currently rig it with the tack attached to the anchor roller via a line and block. The tack line is run back to the cockpit to allow adjustment to raise or lower the tack. The sheet lines are of course run back to the cockpit via blocks outside of the rigging. The Spinaker is a 1.5 oz with a "dosing sock" I got it with the boat. Questions: Last week while on a broad reach we hoisted the sail. True wind was 5 knots. Apparaent wind was on the beam. Anyway, the luff edge of the sail kept collapsing. Is there any general rule about the sail trim with this sail? In this case should I have tightened the luff edge? I'm just looking for some help on when and how to trim this thing. Q#2: at what point should I NOT use this sail in regards to wind strength? I would think I could get overpowered pretty quick. I've only used it on broad reaches and downwind up to 10kts (true). Thanks, Bob s/v Andiamo
 
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Bill O'Donovan

Good questions

Asymetrical works best on a deep broad reach, which will translate into a beam reach owing to the change in apparent wind. Try to avoid dead downwind for fear of gybing. (The danger is much greater than getting your head knocked off. Eventually it could sheer the bolts right off the mastplate -- happened to me.) Part of your problem may be that the main is blanketing the spin. You can throw the spin out another 4 feet with a clever bowsprit of cast iron that I have perfected. If you're interested, send me your ground mail and I'll forward the pix and directions. Easy and cheap. You don't need (or want) to run the spin when the wind is blowing over 10. If you can see whitecaps, you'll zoom just fine by flying the jib. The danger here is twofold: (1) you get overwhelmed with noise and flapping that could tear the sail, or (2) if you can set it up in a big wind and keep 'er steady it may overpower the boat into a broach that will take the bow under. This is exciting to contemplate but not to experience. There's much about spins in the Archives. It's the ultimate fun for sailors because it tests several skills while achieving excellent speed.
 
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David Foster

Added thoughts

One reaction to your set-up description: Do the sheets go to a block at the stern, and then into the cockpit, or directly into the cockpit? If not, doing so will help the set of the sail. Mu understanding of spinnaker trimming off the wind (as you describe it) is that an occasional flutter of the luff means you have got it right. More significant, or frequent collapses of the luff are a signal to trim the sheet (pull it in). You want to harden the luff by tensioning the tack when you are sailing on a close reach. In light air, our Doyle APC will sail 60 degrees off the _true_ wind. with the luff tensioned. Bill's comments on wind speed are right on. David Lady Lillie
 
Sep 24, 1999
1,511
Hunter H46LE Sausalito
chute stuff

A #1. Your luff should always curl. The moment it starts to collapse, you're pinching, either sheet in or bear off. If it flattens, you're overtrimmed, either ease the sheets or head up. A #2. How much wind you can use your chute in depends on what weight fabric it's made of, usually either 1/2, 3/4, or 1.5 ounces. Most 3/4 oz. spinnakers are good to around 18 knots apparent wind. The best thing to do is check with your sailmaker about the ideal conditions for your particular spinnaker.
 
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Mark Burrows

Luff curl?

Does the luff curl rule apply to asymmetrical spins?
 
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Mickey and Debbie McHugh

Curling on H40.5

Check the photo forum for photos of our Asym (North Genaker). Notice the luff curl. If it is not curling then Yaga is not moving at max speed. We did VERY well beam reaching in the recent Harvest Moon Race that allowed us to fly it for the first 100 miles down the coast of Texas.
 
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ken matejka

wind speed&point of sail

Bob, If your assym is a 1.5 ounce this is a mod/heavy air chute and will withstand winds up to at least 20 true. Having said that, a few qualifiers. 1) your boat will probably not be well balanced (overpowered)if sailing any closer than a beam reach in anything over 12-15 as this sail will create a significant heeling moment secondary to its full draft 2) Remember that as you fall off from a beam reach, your apparent wind speed(wind that the sails are actually feeling)will fall precipitously since your boat(and sails) is now going down wind. So, on a broad reach(shouldn't really go much deeper than this with an assymetric unless you are also using a spin pole) with 8 knots of boat speed in 15 knots of true wind, your sails are really only seeing about 8 knots of breeze(not direct subtraction since the wind is not dead aft) which is certainly within the limits of a 1.5 ounce chute. I do this routinely with my 3/4 ounce chute. Also, If you ever get overpowered by the chute, you can just dump the sheet. Luff curl just means that the sail is trimmed optimally--max speed.
 
Sep 24, 1999
1,511
Hunter H46LE Sausalito
Mark B.

Yes, the luff-curl principle applies to any free-flying sail, whether a conventional spinnaker, an asymetrical, or a mizzen staysail. (Free-flying means that the luff is not hanked.) The only significant difference in trimming an asymetrical is that luff tension is adjusted via the tack. The higher you want to point, the tighter you want the tack. Easing the tack gives the sail more belly for deeper reaching.
 
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