Arne wrote:It looks to me as if ‘Fanshi’s sail only has camber in the front section, and then combined with a hinge in the battens, right? The combination of these two features could possibly move the CP quite far forward.
I wonder; is the same lee helm experienced on the port tack?
Obviously, the simplest remedy is to shift the sail further aft on the mast, and see what happens. If there had been a Fanshi 2 only two months away from launching, I would have suggested that the sail was build with all-cambered panels and with the max-camber point at the middle of the sail. A little late now for that...
Cheers,
Arne
Thank you for that, Arne. As you know, I don't have a technical mind and trying to assess the sail intellectually is probably beyond me. It was very difficult to get a real handle on what was going on in the very changeable conditions, but there was undoubtedly lee helm and it was sufficiently pronounced that at present I would not attempt sailng off the mooring in anything of a breeze. I think it was worse on starbboard tack.
As you say, the obvious first attempt is to haul the sail further aft. I might add some standing luff parrels to help with that. The way I had set up the running luff parrel, although it fitted with PJR's advice, made it bind quite badly and I'm not entirely sure I had hauled it in far enough. The YHP does nothing until there are about 4 reefs in the sail, so the yard is obviously well forward, too.
Suggestions such as altering the rake or adding a mizzen are essentially impossible, but if the worse comes to the worst, it is entirely feasible to take the sail off, add 300 mm to the leech and extend the forward part of the battens with some sort of mandrel and a wrap of glass and epoxy. I should much rather spend my summer sailing than fooling around with all that palaver, so am keeping my fingers crossed that moving the sail aft will do the trick. The wind has blown relentlessly since Sunday morning and I haven't had a chance even to raise the sail again. To be honest, reaction and a month of 12-hour days have left me exhausted and I'm surprised I've even managed to think it through as much as I have!
I still have an incredibly feeble Internet signal, so can't send and receive much in the way of images.