International 14 Mailing List
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From: Peter Rundle (psrundle@ozemail.com.au)
Date: Thu 29 Jul 1999 - 12:47:49 BST
> who would like to see racks extending behind the transom, to allow us
> to really drive the boats downwind.
About 18 months ago I put a gantry on my boat 12' skiff style that
could be trapezeed off. This caused a lot of contraversy at the
Perth nationals and in the end it was one of the reasons why I sold
my 14. However, I learnt a lot and none it was really all that
surprising
to anyone who's stopped to think about it.
It made a huge difference to the nose dive factor. The gantry was built
so that you could get up to 400mm behind the transom. The idea being to
do the 12' thing with the skipper entirely on the gantry and the crew
interlaced with aft foot on the gantry and front foot in the last
fruttie
on the hull. This was way way too much. At first we often made the
mistake of standing too far aft and stalling the boat on the backs of
waves. In the end we just used to sail with only my rear foot on the
gantry and my crew had her rear foot in the last fruttie on the hull
front foot well forward. I think that a 300mm or even just 250mm
extension is plenty far enough. I doubt that the rule needs to limit
this as if you stand too far aft it's safe but slow slow slow.
Getting on to the gantry is dead easy and after a while you don't even
notice you're doing it. The comfort factor too was great, the two of
us weren't on top of each other, she could work the kite without
giving me an upper cut to the jaw, and I was no longer always on the
verge of losing steering control with her pushing me off the transom. We
still tended to interlace our feet for windage and security though.
It doesn't make the boat go faster in terms of top speed, it just lets
you keep the hammer down when you might otherwise back off. We did a
sprint with another 14 in Perth, starting in the very flat water near
the windward shore and heading out into the bay. The wind was 25-30kts.
We were neck and neck until it got choppy, then we just left them for
dead as we kept the peddle down and they had to flag the kite.
The boat also starts to do this kinda scarry thing where it literally
leaps from wave top to wave top, there's this split second of silence
and a floating sensation, then a WAM as you hit the top of the next
wave. But you get used to it.
Observers on the shore said that our boat was pitching back and forth
more than the others. I think you need to learn where the fine line is
between safety and speed. Too far aft is slow, the pitching energy is
wasted boat speed.
The top mark bearaway in strong winds becomes a delight you just step
back and pull on the tiller extension. The boat pivots on it's transom
and then takes off.
Hovever there is still a limit, you can't cross Manly ferry wakes with
impunity. Whilst we never cartwheeled or nosed the boat in, we still
flagged the kite to cross the big wakes, but we never one wired
anywhere again and that included a 30kt plus southerly on Sydney harbour
against the 12's. Man that day was a hoot, these 12's rounded beside
us and thought that they'd take us downwind and they stood back on their
gantry's and then we stood back on ours and they just couldn't pass us.
As to the fact that it will lead to finner, flatter hulls I don't accept
that. The hulls are already as fine as the rules will allow, and fine
hull are less nosey than fat ones anyway. Dead flat is not fast. I don't
think anyone would suggest that a boat with a hogged bottom would
be fast so if you chart speed on the Y axis against rocker on the X
axis then there must be a point somewhere that will be the best for
all round performance. That point obviously ain't hogged so unless you
think that the curve has a sudden sharp drop when the rocker becomes
dead flat then the optimum point must be somewhere back from that
spot. In my opinion it's quite a way back. I have raced boats with as
little as 1" of rocker and they are obviously too far on the flat side
of the optimum. Very flat boats are not a good all round shape, sure
they
can be really quick in narrow ranges, typically just on the edge of the
planning magins, but upwind speed is the key to winning races and flat
boats just don't have a good enough range especially when it's light,
but
generally upwind is a planning semi-displacement proposition and you
need
subtle lines forward not flat as a tack.
Anyway for what it's worth I still think that it was the best $200 I
spent on my boat and insurance from cartwheels and mast breakages
alone makes it worth it. But as a 12' footer said, "Hell if you want to
one wire downwind why don't you buy a Cherub."
rgds
Pete
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