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Jeff Morris
 
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Default Never run downwind?

Hey Neal - you're beginning to sound like Jax. What's next - are you going to claim
Einstein proved you can't navigate in the fog?

I wouldn't expect an English major to remember any high school trigonometry (assuming you
ever passed the course) but it only takes a simple calculation to show that you only go 4%
further when you run at 165 degrees instead of 180. You only have to go a little faster
to make this up. In fact, you only have to go 15% faster to make up the difference in
running at 150 degrees. Thus, you can jibe through 60 degrees true and only need a 15%
increase to make it worth while.

Here's a polar for a Catalina 36. I don't think anyone would call this a planing boat,
especially in light air:

http://albertson.sytes.net/~chris/C3...6Polars_al.gif

The chart clearly shows that you can go 25% faster in light air by jibing downwind in
light air.

Are you claiming that all the Polar Diagrams are false?


"Simple Simon" wrote in message
...
A displacement boat that does not plane will always
arrive at a destination in less time by running directly
downwind to it. Gybing downwind does result in slightly
faster speed through the water in lighter winds but the
extra distance traveled results in a longer time to arrive
at the destination. This is just plain common sense and
physics at work. Anyone who claims something different
is living in Lala Land. You're beginning to sound as
stupid and ignorant as Jeff Morris.


wrote in message

...
On Thu, 17 Jul 2003 18:46:06 -0400, "Simple Simon" wrote:

That is incorrect information for any displacement monohull where
it is always faster to run straight downwind.


Baloney! An under canvassed tank like yours or Bobadil's might benefit quite a
bit from gibeing back and forth rather than going directly downwind. I do better
going strait downwind, because I can put up the mylar main and 170 genoa, or a
spinnaker and take advantage.

BB