RE: Sail plan:

Eric Johnson (ej@tx3.com)
Mon, 14 Dec 1998 10:14:45 -0800


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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> Eric adds:
> >In fact, the measurements for the main are a real joke - Even
> with an 8-ft
> >boom and full hoist of the entire mast (not counting roach) you could
> >only get 88 sq. ft, and thats with the boom scraping on the cabintop.
> >
> >Something to keep in mind anyways if you ever want to race PHRF or
> >whatever - get your boat rated on actual sail area, not on the
> IM numbers.
> >
> >Another annoyance, but i still love my boat.
>
> Remember from last year's thread about PHRF that boats under 20 feet LOA
> aren't eligible for official PHRF certificates.

Not true for PHRF-NW, where they allow all boats over 18ft OAL. But I
haven't taken the plunge yet with them but I might.

<snip>
> There seem to be three sailplan variables that affect the size of sails
> delivered with P19s. Tall vs short mast, long vs short boom, and masthead
> vs. fractional rig. I think this works out to 8 possibilites, of which I
> have tall mast, short boom, fractional rig (TSF). Of these 8 (?),
> undoubedly one is superior to the rest, and it might be
> constructive to use
> the winter months to develop a concensus as to which.

My understanding is that all P19s have the same (theoretical) forestay
length - buts its a masthead rig on a short rig, and a fractional on a tall
rig. There are probably vessels out there that have been modified. I wonder
if the boat with the 21.5" mast had been shortened for some reason in the
past?

> I intuit that tall mast, short boom, and masthead rig would be the best
> configuration. Comment?

For a given sail area, I agree, because that arrangement gives the highest
aspect ratios which reduce induced drag. But I don't think the P19 was ever
really offerred that way. Obviously you can carry more sail with a tall
mast, long boom, masthead rig... but I wouldn't want to carry that much sail
since a long boom eliminates the possibility of a backstay.

Speaking of induced drag, I think the rudder and daggerboard could benefit
greatly from some re-shaping around the lower trailing edge.