Received: from hplms26.hpl.hp.com by opus.hpl.hp.com with ESMTP (1.37.109.18/15.5+ECS 3.3+HPL1.1) id AA099119723; Mon, 3 Mar 1997 12:08:43 -0800 Return-Path: <Geoffrey.Boehm@wj.com-DeleteThis> Received: from gatekeeper.wj.com by hplms26.hpl.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3+HPL1.1S) id AA161179723; Mon, 3 Mar 1997 12:08:43 -0800 Received: (from uucp@localhost) by gatekeeper.wj.com (8.6.9/8.6.9) id MAA05893; Mon, 3 Mar 1997 12:01:03 -0800 Received: from internal.wj.com(144.172.15.212) by gatekeeper via smap (V1.3) id sma005846; Mon Mar 3 12:00:36 1997 Received: from ccsmtp.wj.com by internal.wj.com with SMTP id AA17504 (5.67b/IDA-1.5); Mon, 3 Mar 1997 12:00:35 -0800 Received: from ccMail by ccsmtp.wj.com (IMA Internet Exchange 2.02 Enterprise) id 31B316D0; Mon, 3 Mar 97 12:15:41 -0800 Date: Mon, 3 Mar 1997 12:00:20 -0800 Message-Id: <31B316D0.1264@ccsmtp.wj.com-DeleteThis> From: Geoffrey.Boehm@wj.com-DeleteThis Subject: Re[2]: Flat sails To: Multiple recipients of list <wind_talk@opus.hpl.hp.com-DeleteThis>, alain@paris.engr.sgi.com-DeleteThis (Alain Dumesny) Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Description: cc:Mail note part
I think that it depends on the sail. I have a 4.5 ezzy transformer
that I tune by flattening, with the flattest setting approximately 2"
tighter than the loosest. The difference is remarkable, and though the
flattest setting is pretty gutless at the low end, it makes the sail
handle more like a 4.0 when the wind is strong, with no deterioration
in any handling characteristics.
______________________________ Reply Separator _________________________________
Subject: Re: Flat sails
Author: alain@paris.engr.sgi.com-DeleteThis (Alain Dumesny) at INTERNET
Date: 3/3/97 11:45 AM
> From: <bo3b@apple.com-DeleteThis>
>
> His recommendation for overpowered is to partly flatten the sail to
> reduce the power, but still keep a curve. You don't want the full bodied
> curve, since you don't need that power, but you don't want it flat either.
>
> Then, the even better way to reduce power is to put on more downhaul, so
> the leech gets looser, even down to the boom, spilling more wind,
> handling stronger gusts, but keeping an airfoil.
>
I will also agree with that. Typically when I'm way overpowered, I will
downhaul FIRST to make the sail very loose (or get rid of the loose leach if
underpowered). Amazing how much more wind a modern sail with a lot of
downhaul will take. I use a FlipAndEasy which makes is pretty easy to adjust
and it also gives you a lot of leverage. I have to come off the water though.
After that, I add some outhaul to tension the sail again.
If I need to flatten the sail a little bit, I would do it at most 1/2 in, if
even that much (which I can do while in the water). Flat sails don't handle
more wind. Loose leach sails on the other hand can spill a lot of the gusts.
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