PHRF So Cal rates your boat at 228, which makes it slower than a Catalina
27, Pearson 25, Cal 27, even a lowly Mac26x!!! A quick examination of the
list revealed only 2 slower 27 footers, an Ericson and a Tartan, both of
which are miles ahead of your boat, quality wise, that is. Also C&C, O'Day,
and probably a few others I've missed, speed wise, that is.
http://www.phrfsocal.org/
The thing about the ratings for older boats is that they tend to be a little
more accurate as these boats have been around for a while and if they are
faster than their ratings indicate they usually get adjusted to reflect
this.228 is about as fast as any Coronado 26 will ever get, including yours.
I think the thing that would be really humiliating would be to get beat by a
Mac26x!

John Cairns




"Simple Simon" wrote in message
...
FEAR THIS!

Now I understand why my boat is so uncommonly fast.

It is because she has a LWL of 25 feet instead of the
commonly listed 22 feet.

You can see and measure for yourself

http://captneal.homestead.com/Sheshines.html

Use the top picture and get out your dividers.

Measure the LOA. You computer screen size will make your
measurments vary from mine but not too worry use what you get.

The LOA I measured at 27 feet is 12.5mm
The LWL I measured at X is 11.6mm.

Now all we have to do is solve for X

X times 12.5 = 27 times 11.6

or X = (27) (11.6) divided by 12.5

or X = 25 feet.

With a LWL of 25 feet the hull speed is the same as
Moroon's 30-footer and Booby's 32 footer.

A picture is worth a thousand words.

8200, which drops your SA/disp down to a dismal 10.7! While your ultimate
speed may be
faster, your medium air performance is now pathetic.

Slam.
That was harsh, Jeff.

RB

I must apologies to Neal - when ran the added 2000 pounds through SailCalcPro the SA/disp
came out to 11.83, still lower than any production boat I know of. I've certainly seen
some loaded to where they are in single digits. Neal would have to add over 3000 pounds
to get down to what I quoted - but that's possible too - it would mean being about 4.5
inches below her lines.

Running the VPP number for +2000:
At 14 kts, the sail still generates 6 hp, but this is now 1375 pounds/hp, instead of 1000.
This will push him at .95 of sqrt(LWL), which with the increased waterline, which comes
out to 4.75 knots. The original calculation yielded 4.9 knots, so there is a net loss.
In lighter wind he has more wetted surface, and although his ultimate hull speed may be
higher, he has to carry full sail in well over 20 knots to get there. The 20 knot
prediction leaves him at 1.2 sqrt(LWL), or 6 knots, instead of 6.3.

One might claim that this is a small penalty to pay for carrying your life's possessions
with you. And I'm not sure I'd like know what my boat weighed the day we left for the
trip. But its pretty clear that increasing the LWL by loading the boat does not make it
faster.

One more thought - I think Neal gained LWL by submersing the aft section, just forward of
the transom. I haven't been able to find a design drawing to confirm this - is it
possible Tripp had them all destroyed? If this is the cause for the seeming discrepancy,
then this extra waterline would have become available whenever he went fast enough to
generate a stern wave. This is a common design trick - the overhangs create additional
effective waterline as the wave making resistance goes up. So by loading the boat, one
does not actually gain LWL, one gains wetted surface and more weight to pull around.

I hope a few people have appreciated this exercise at Neal's expense. I always wanted to
run these calculations and compare them to real life. My primary source was Dave Gerr's
"The Nature of Boats." If I can find a more formulaic expression of this, I might make a
little calculator, like SailCalcPro.


--
-jeff www.sv-loki.com
"I wish to have no connection with any ship that does not sail fast; for I intend to go in
harms way." - John Paul Jones


"CANDChelp" wrote in message
...
8200, which drops your SA/disp down to a dismal 10.7! While your ultimate
speed may be
faster, your medium air performance is now pathetic.

Slam.
That was harsh, Jeff.

RB

I've raised the boot stripe about 8 inches over the years.


"Wally" wrote in message ...
"Simple Simon" wrote in message

I think the original figure is with an empty boat that floats
much higher up in the water. Even then I think the LWL
would be greater than 22 feet, though.

I would agree with that - 3 feet is a lot to lose. Looking at the port-side
view on...

http://captneal.homestead.com/haulout.html

...I estimate 22 feet from the stern to end somewhere between the stand
under the bow and the dark object in the background just to its left.


Another thing is
the shoal keel is about five hundred pounds heaver
than the stantard keel so mine, which is a shoal keel,
floats deeper in the water to begin with even when not
loaded for cruising and living aboard.

Does the line of your blue antifoul leave the same nominal freeboard as
Coronado 27s with the standard keel?


--
Wally
I demand rigidly-defined areas of uncertainty!
www.art-gallery.myby.co.uk

"katysails" wrote in message news:bfq7c5

Are you saying my cat's LOA is 9 feet longer?

My God, you have a tiger????

No he has a domestic cat, and a rack in his torture chamber.


--
Wally
I demand rigidly-defined areas of uncertainty!
www.art-gallery.myby.co.uk

The original calculation yielded 4.9 knots, so there is a net loss.
In lighter wind he has more wetted surface, and although his ultimate hull
speed may be
higher, he has to carry full sail in well over 20 knots to get there. The 20
knot
prediction leaves him at 1.2 sqrt(LWL), or 6 knots, instead of 6.3.

As neal says, math tells the truth.

RB

Actually, my youngest feline is lilac-point Siamese with very long bones. Stretched out
(on the rack) he's well over 3 feet.

"Wally" wrote in message
...
"katysails" wrote in message news:bfq7c5

Are you saying my cat's LOA is 9 feet longer?

My God, you have a tiger????

No he has a domestic cat, and a rack in his torture chamber.


--
Wally
I demand rigidly-defined areas of uncertainty!
www.art-gallery.myby.co.uk

See, Bobsprit, how a real troll master does it.

Your trolling efforts only result in people doing minor
work typing some insults in reply to your taunts while
my expert trolls result in people spending all night
reading books and doing math .. .. . . .


I'm the master. Bwaa ah ahah ha ha hhahaha!


"CANDChelp" wrote in message ...
The original calculation yielded 4.9 knots, so there is a net loss.
In lighter wind he has more wetted surface, and although his ultimate hull
speed may be
higher, he has to carry full sail in well over 20 knots to get there. The 20
knot
prediction leaves him at 1.2 sqrt(LWL), or 6 knots, instead of 6.3.

As neal says, math tells the truth.

RB

You forget I'm a retired engineer/programmer. I did this for a living for 25 years, and
miss it a bit. I used to be doing this for $100 an hour, now I can do it for free!


"Simple Simon" wrote in message
...
See, Bobsprit, how a real troll master does it.

Your trolling efforts only result in people doing minor
work typing some insults in reply to your taunts while
my expert trolls result in people spending all night
reading books and doing math .. .. . . .


I'm the master. Bwaa ah ahah ha ha hhahaha!


"CANDChelp" wrote in message
...
The original calculation yielded 4.9 knots, so there is a net loss.
In lighter wind he has more wetted surface, and although his ultimate hull
speed may be
higher, he has to carry full sail in well over 20 knots to get there. The 20
knot
prediction leaves him at 1.2 sqrt(LWL), or 6 knots, instead of 6.3.

As neal says, math tells the truth.

RB

Which is of paramount importance when your passage making consists of
sailing around your mooring block.

"Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message

However, your "motion comfort" is very high.