From: scott@soldev.tti.com (Scott Taylor)
Subject: Re: Tuff Luff and other headstay foils
Organization: Transaction Technology Inc.
Date: Fri, 20 Nov 1992 16:47:21 GMT

In article <1992Nov17.215451.3441@klaava.Helsinki.FI> tarkkone@klaava.Helsinki.FI (Lauri Tarkkonen) writes:
>In <guido.722012392@sparc-3> guido@blink.att.com (Guido Bertocci) writes:
>
>>tarkkone@klaava.Helsinki.FI (Lauri Tarkkonen) writes:
>
>>>In <1992Nov13.185255.4694@ttinews.tti.com> scott@soldev.tti.com (Scott Taylor) writes:
>>>>I am afraid that you know not of what you speak. When sailing bare headed
>>>>you lose both boat speed and pointing ability. On a large boat, where a 
>>>>headsail change will take 3-5 minutes with hanks, you could easily lose
>>>>30-40 boat lengths.
>
>>I've crewed on a C&C 35 with hanks and it never took us that long to
>>change head sails.  Our procedure involved undoing the lower hanks
>>on the jib that is still up,  attaching the new jib in the space vacated
>>by the current jib hanks.  When the new one was completely attached, the
>>old one was "de-hanked" as it came down.  As soon as old one was completely
>>off the new one was hoisted.  Hoisting a hanked sail is very fast.
>>We were probably completely without headsail for only 15-20 seconds.
>>While this boat was relatively low tech with a lousy handicap we often beat 
>>much faster boats by not screwing up boat handling and paying attention
>>to tell tales and wind shifts.  We also ate real well since
>>we made good food a priority :-). 
>
>As I said, if you compare badly executed hank sail change to a well executed
>foil change there is a real difference. Because people interested in winning
>races invest more in practice as well as equipment Mr. Scot might be under
>the false impression that there is a really big difference between the
>two procedures, when the real difference was between the crews. :-).
>Maybe I am not that stupid after all. ;-).
>

No. You're still stupid. You just don't have an exclusive claim to the
term anymore. 

Okay, I'll go slow. Compare two identical boats, lets say Santa Cruz
70's. One has a wire headstay, the other has a foil. Now, let's assume
that they are on a beat on a long upwind leg, say ~10 miles to go. They
both have a light number one up. The wind has freshened from ~4 knots to
~12 knots and building. Time to change headsails. Oh, yeah, and lets
also assume that the crews are equally skilled and the two boats are 
racing side by side.

The boat with the foil continues to sail on course, while raising the
number 2 inside of the number 1. They drop the number one behind the 
number two and lose very little boat speed in the process.

The boat with hanks, hanks on a new sail below the existing sail and
begins to lower the number 1. Their mast is about 90' high with a 
piston hank every 5 feet along the luff, so 18 hanks at three seconds 
each to undo. That's 54 seconds with the sail flapping around on it's 
way down. During that 54 seconds you had to bear off 15 degrees, because
the boat was really designed to sail with a headsail and not with a main
alone. Now you have to raise the new sail, get it sheeted in and adjust
to the new course.

Now, which boat do you think is ahead of the other in this race?
Remember that the boats are identical, the crews are equally skilled
and the conditions are the same. The only difference is that one 
boat has a foil and the other does not.

>- Lauri Tarkkonen


Scott Taylor, Citicorp/TTI
pyramid!ttidca!scott
(310) 450-9111 x2321
From: bsmith@hplvec.LVLD.HP.COM (Brian Smith)
Date: Tue, 17 Nov 1992 20:06:48 GMT
Subject: Re: Outboard HP
Organization: Hewlett-Packard Co., Loveland, CO