leach luffing

[Al]

I have read (and experienced on our 356) about a main sail leach luff that occurs only with the furling jib extended. It does not occur when using the mainsail alone. The leach cord has been adjusted by the service department, but it still occurs. The boat is still under warantee. Have you heard of this? Is it correctable?

 

[Bill Colombo at Doyle Sails]

Leech Luff or Flutter?

Al, I am not exactly sure what you are referring to but I have some ideas. If the leech is fluttering while sailing, then you would stop it by tightening the leech chord, but this would happen whether the headsail was flying or not. Probably what is occuring is what we call "blow back" which is air flow forced into the leeward side of the mainsail by the genoa. This occurs more often in older sails where the maximum draft position has moved aft over time. There are a few fixes you might try. First make sure that the leech chord on the genoa is not too tight, causing a pronounced hook in the leech. Next check the lead position to see if you can move the sheet lead aft a bit which will increase twist, and allow the air to flow more freely through the slot. If neither of these work you might have a sailmaker look at the shape of the sail to see if you need a small recut to flatten out the exit on the genoa.Bill Colombo, Doyle SF

 

[Chuck Wayne]

356 flutter

Al, what you're experiencing appears to be common with the stock UK sails Hunter provides on the 356's and other boats. Bill's comments don't really address the problem-it's only a 110 jib, and adjusting the leads doesn't seem to matter. Also, if you loosen the leechline so it isn't cupped, you get severe vibration that shakes th whole boat. We all need to complain to Hunter about the quality of their standard sails. I also think the draft is pretty far aft on my sails, even though they're new. The response I've heard, second hand, from Hunter is that these are "delivery sails" and we shouldn't expect them to perform. We've taken delvery on a Doyle swingbatten, I'll publish a full report once we're back in the water.Chuck WayneH356 WWW.Escape