Claiming that a CR 38 will do 11 knots is
a bit of a stretch, don't you think?

Well you should remember that the Boobster told us he did 13kts in 8kts of wind
with his 70s era tub.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"

Don't remember that one, but I was surprised by Mooron's statement, so
surprised that I let it pass for a while. When I first saw the statement
"11kts in 6 ft of water" my initial reaction is that he was loaded and got
the numbers backwards. Then he insisted it was correct, and offered to post
proof in the form of log entries that he was going to post to his webshots
album. In any event, got some info from folks on the Cabo Rico list, at
least one of whom indicated that the CR38 is slower than I imagined, even
got an offer to take a tour of a boat in Port Clinton, Ohio, hope to do that
before the season ends.

"If you are going to windward, a 150 mile day is going to be hard to do. On
a
reach or downwind with the right sails it is easy to do. The CR38 has a 29
ft
waterline so it does about 7kts if the wind and sails are right, and
because
it has a full keel (lots of wetted surface) the bottom needs to be kept
clean"

Quote from an owner, which were my thoughts about hull speed, too much
wetted surface, too short a LWL. Still a great blue water boat, just not a
fast one.

John Cairns

"SAIL LOCO" wrote in message
...
Claiming that a CR 38 will do 11 knots is
a bit of a stretch, don't you think?

Well you should remember that the Boobster told us he did 13kts in 8kts of
wind
with his 70s era tub.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"

John you can be as surprised as you like.... I'm certain of the figures but
won't have the documentation to offer until well into the middle of next
month.

Insofar as the owner's response..... there is a Nordica 30 owner right
here with a sister ship to mine that claims he has never gotten beyond 6
knots of speed from the vessel. I understood that statement when I first
sailed along side him in my boat. His vessel will not do over 6 knots... but
it has nothing to do with the vessel's abilities and all to do with it's
set-up and handling.

Now you'll tell me that a speed of over 9 knots sustained is impossible on
Overproof I suppose!

CM

"John Cairns" wrote in message
om...
| Don't remember that one, but I was surprised by Mooron's statement, so
| surprised that I let it pass for a while. When I first saw the statement
| "11kts in 6 ft of water" my initial reaction is that he was loaded and got
| the numbers backwards. Then he insisted it was correct, and offered to
post
| proof in the form of log entries that he was going to post to his webshots
| album. In any event, got some info from folks on the Cabo Rico list, at
| least one of whom indicated that the CR38 is slower than I imagined, even
| got an offer to take a tour of a boat in Port Clinton, Ohio, hope to do
that
| before the season ends.
|
| "If you are going to windward, a 150 mile day is going to be hard to do.
On
| a
| reach or downwind with the right sails it is easy to do. The CR38 has a 29
| ft
| waterline so it does about 7kts if the wind and sails are right, and
| because
| it has a full keel (lots of wetted surface) the bottom needs to be kept
| clean"
|
| Quote from an owner, which were my thoughts about hull speed, too much
| wetted surface, too short a LWL. Still a great blue water boat, just not a
| fast one.
|
| John Cairns
|
| "SAIL LOCO" wrote in message
| ...
| Claiming that a CR 38 will do 11 knots is
| a bit of a stretch, don't you think?
|
| Well you should remember that the Boobster told us he did 13kts in 8kts
of
| wind
| with his 70s era tub.
| S/V Express 30 "Ringmaster"
| "Trains are a winter sport"
|
|

"Capt. Mooron" wrote in message
...
John you can be as surprised as you like.... I'm certain of the figures
but
won't have the documentation to offer until well into the middle of next
month.

Insofar as the owner's response..... there is a Nordica 30 owner right
here with a sister ship to mine that claims he has never gotten beyond 6
knots of speed from the vessel. I understood that statement when I first
sailed along side him in my boat. His vessel will not do over 6 knots...
but
it has nothing to do with the vessel's abilities and all to do with it's
set-up and handling.

Now you'll tell me that a speed of over 9 knots sustained is impossible on
Overproof I suppose!


You are getting as bad as Bob.

A sustained speed of 9kts (through the water) is impossible in Overproof.


In fact, I've never managed much more than 8kts over two hours. Setanta is
designed to surf!!



Regards


Donal
--

Have no idea how fast a Nordica 30 is, don't recall seeing phrf #'s. Never
attempted to do any reverse calculations, ie., how fast is a particular boat
based on it's phrf #, but I feel it is a useful tool when comparing boats of
similar length. BTW, more than one responder on the CR list told me they
didn't consider their CR38 to be a fast boat, no one, including the lake
sailors, claimed their boat would do 11 kts.

SPEED/LENGTH RATIO (V/ L.5): This is the speed in knots divided by the
square root of the LWL. For example, a 25 foot waterline sailboat moving at
5.5 knots would be at a V/ L.5 of 1.1. while a 400 foot LWL destroyer
travelling at 22 knots also has a V/ L.5 of 1.1. Both vessels would develop
about the same resistance per ton of displacement as they are both running
at the same V/ L.5.
The limiting speed for a pure displacement hull is a V/ L.5 of 1.34. Above
this speed the stern wave moves aft so that the stern loses bouyancy, the
hull squats, and great additional power is necessary for a small gain in
speed. In truth, the typical cruising sailboat probably averages a V/ L.5 of
about .9 - 1.0 and only gets close to 1.3 when reaching in a stiff breeze.
Tender boats may never get above 1.2 as the crew has to ease sheets when the
rail buries!

The modern beamy, super light ocean racer can have a stern wide enough to
resist squatting and the stability to stand up to a breeze so often achieves
speeds well above 1.4, but that is semi-planing and the boat is getting lift
aft due to its speed. My BOC 60 design exceeded 20 knots at times, a V/ L.5
ratio of over 2.6, but those are very specialised yachts.

Ted Brewer " Understanding Boat Design 4th. Edition"

http://www.tedbrewer.com/yachtdesign.html

John Cairns



"Capt. Mooron" wrote in message
...

John you can be as surprised as you like.... I'm certain of the figures
but
won't have the documentation to offer until well into the middle of next
month.

Insofar as the owner's response..... there is a Nordica 30 owner right
here with a sister ship to mine that claims he has never gotten beyond 6
knots of speed from the vessel. I understood that statement when I first
sailed along side him in my boat. His vessel will not do over 6 knots...
but
it has nothing to do with the vessel's abilities and all to do with it's
set-up and handling.

Now you'll tell me that a speed of over 9 knots sustained is impossible on
Overproof I suppose!

CM

"John Cairns" wrote in message
om...
| Don't remember that one, but I was surprised by Mooron's statement, so
| surprised that I let it pass for a while. When I first saw the statement
| "11kts in 6 ft of water" my initial reaction is that he was loaded and
got
| the numbers backwards. Then he insisted it was correct, and offered to
post
| proof in the form of log entries that he was going to post to his
webshots
| album. In any event, got some info from folks on the Cabo Rico list, at
| least one of whom indicated that the CR38 is slower than I imagined,
even
| got an offer to take a tour of a boat in Port Clinton, Ohio, hope to do
that
| before the season ends.
|
| "If you are going to windward, a 150 mile day is going to be hard to do.
On
| a
| reach or downwind with the right sails it is easy to do. The CR38 has a
29
| ft
| waterline so it does about 7kts if the wind and sails are right, and
| because
| it has a full keel (lots of wetted surface) the bottom needs to be kept
| clean"
|
| Quote from an owner, which were my thoughts about hull speed, too much
| wetted surface, too short a LWL. Still a great blue water boat, just not
a
| fast one.
|
| John Cairns
|
| "SAIL LOCO" wrote in message
| ...
| Claiming that a CR 38 will do 11 knots is
| a bit of a stretch, don't you think?
|
| Well you should remember that the Boobster told us he did 13kts in
8kts
of
| wind
| with his 70s era tub.
| S/V Express 30 "Ringmaster"
| "Trains are a winter sport"
|
|

"John Cairns" wrote in message
m...
| Have no idea how fast a Nordica 30 is, don't recall seeing phrf #'s. Never
| attempted to do any reverse calculations, ie., how fast is a particular
boat
| based on it's phrf #, but I feel it is a useful tool when comparing boats
of
| similar length. BTW, more than one responder on the CR list told me they
| didn't consider their CR38 to be a fast boat, no one, including the lake
| sailors, claimed their boat would do 11 kts.

It's not supposed to be fast.... look at the stats on SailCalc. Never the
less I often have the boat exceeding her theoretical hull speed. I have
raced boats that are supossedly faster according to both phrf and hull speed
calcs.... unfortunately the realities of extraneous inputs on the vessel
can throw a spanner into the works and those supposedly faster boats are not
performing to their stated potential..

Now seriously... are you claiming that a 38 foot cutter with a full keel and
cut-away forefoot cannot achieve 11 knots of speed because her theoretical
hull speed is rated at 7.3?

The thing about the numbers is that they are general benches for estimation.
To state flat out that a vessel can not exceed her calculated hull speed is
erroneous. My 30 footer has attained speeds well in excess of her
theoretical hull speed.... 10+ knots over a nautical mile... mind you we
were flying all the laundry and the wind was dead astern at 36 kts gusting
to 42 kts. You've seen her hull shape John... surfing isn't an option
here.... she was pushing water hard with the bow biting down.!

CM

The "theoretical" nature of the calculator relates to hull shape/wetted
surface, which it doesn't account for, and waterline length, which changes.
It doesn't consider if a boat can plane, which is an entirely different
ballgame. It does offer a pretty close estimate of how fast a displacement
boat can travel, power or sail. If the calculator wasn't fairly accurate, it
would be pointless, wouldn't it? Are you saying a CR38 can plane upwind? I
would find that extremely hard to believe, considering hull shape and
displacement. Now I have seen the calculator with the addendum that it
applied to boats with D/L ratios of over 150, but again the author was
referring to the ability to plane. The CR38 has a ratio of 359, which makes
it well over 150. I think if you quiz any NA they'll agree. Not my ideas,
just passing them along. Will a CR38 exceed it's theoretical hull speed?
Sure. Will it exceed it's theoretical hull speed by 50%. I don't think so.

" The slowest the CR is, is into the wind in heavy chop, 4 to 8 ft seas
close together. The boat does not ride up and down them, it kind of goes
through
them, EACH WAVE SLOWING THE BOAT DOWN. I find it best to fall off some and
power up the sails, it gives a nicer ride but slows your vmg to 3 kts or
so.
Remember gentleman never sail upwind."

My caps for emphasis.

And another personal response:

"No we don't normally need to reduce sail until the gets around 25kts. I
recently left Lemmington in Canada in 25 gusts to 35. We had one reef in the
main and staysail. We averaged 6.8 kts for 6 hours to Huron,OH and were very
comfortable."

Now I don't know what direction the wind was coming from, but even if the
wind was on his nose, he wasn't doing 11 kts. Could he have done 11 kts. in
a planing hull? Probably, but I don't think he would have been very
comfortable, either. And considering the probable sea state-by the time he
reached the half-way point the lake would have been fairly choppy regardless
of the wind direction-6.8 kts. is a pretty good speed.

John Cairns


"Capt. Mooron" wrote in message
...

"John Cairns" wrote in message
m...
| Have no idea how fast a Nordica 30 is, don't recall seeing phrf #'s.
Never
| attempted to do any reverse calculations, ie., how fast is a particular
boat
| based on it's phrf #, but I feel it is a useful tool when comparing
boats
of
| similar length. BTW, more than one responder on the CR list told me they
| didn't consider their CR38 to be a fast boat, no one, including the lake
| sailors, claimed their boat would do 11 kts.

It's not supposed to be fast.... look at the stats on SailCalc. Never the
less I often have the boat exceeding her theoretical hull speed. I have
raced boats that are supossedly faster according to both phrf and hull
speed
calcs.... unfortunately the realities of extraneous inputs on the vessel
can throw a spanner into the works and those supposedly faster boats are
not
performing to their stated potential..

Now seriously... are you claiming that a 38 foot cutter with a full keel
and
cut-away forefoot cannot achieve 11 knots of speed because her theoretical
hull speed is rated at 7.3?

The thing about the numbers is that they are general benches for
estimation.
To state flat out that a vessel can not exceed her calculated hull speed
is
erroneous. My 30 footer has attained speeds well in excess of her
theoretical hull speed.... 10+ knots over a nautical mile... mind you we
were flying all the laundry and the wind was dead astern at 36 kts gusting
to 42 kts. You've seen her hull shape John... surfing isn't an option
here.... she was pushing water hard with the bow biting down.!

CM

"John Cairns" wrote in message
m...
| The "theoretical" nature of the calculator relates to hull shape/wetted
| surface, which it doesn't account for, and waterline length, which
changes.
| It doesn't consider if a boat can plane, which is an entirely different
| ballgame. It does offer a pretty close estimate of how fast a displacement
| boat can travel, power or sail. If the calculator wasn't fairly accurate,
it
| would be pointless, wouldn't it? Are you saying a CR38 can plane upwind? I
| would find that extremely hard to believe, considering hull shape and
| displacement. Now I have seen the calculator with the addendum that it
| applied to boats with D/L ratios of over 150, but again the author was
| referring to the ability to plane. The CR38 has a ratio of 359, which
makes
| it well over 150. I think if you quiz any NA they'll agree. Not my ideas,
| just passing them along. Will a CR38 exceed it's theoretical hull speed?
| Sure. Will it exceed it's theoretical hull speed by 50%. I don't think so.

John ... at 11 kts it's only 3.7 kts above it's hull speed. I said it was
upwind but never said it was a close reach. Really John... you've been on
the ocean. I get a 42 mile passage in 5 hours from dock to dock on my 30
footer in seas that crest at 12 feet plus swells, gale force at 34 kts wind
and gusting..... big deal. That's not a big stretch!


|
| " The slowest the CR is, is into the wind in heavy chop, 4 to 8 ft seas
| close together. The boat does not ride up and down them, it kind of goes
| through
| them, EACH WAVE SLOWING THE BOAT DOWN. I find it best to fall off some
and
| power up the sails, it gives a nicer ride but slows your vmg to 3 kts or
| so.

Okay.. but I was describing a crossing of Yellowbanks... which has no such
chop. I think we all know the effects of chop and confused seastates.

|
| "No we don't normally need to reduce sail until the gets around 25kts. I
| recently left Lemmington in Canada in 25 gusts to 35. We had one reef in
the
| main and staysail. We averaged 6.8 kts for 6 hours to Huron,OH and were
very
| comfortable."

I can claim likewise performance for my 30 footer.

|
| Now I don't know what direction the wind was coming from, but even if the
| wind was on his nose, he wasn't doing 11 kts. Could he have done 11 kts.
in
| a planing hull? Probably, but I don't think he would have been very
| comfortable, either. And considering the probable sea state-by the time he
| reached the half-way point the lake would have been fairly choppy
regardless
| of the wind direction-6.8 kts. is a pretty good speed.

Fine John... you described a passage with minimal input. Of course he wasn't
doing eleven knots .... he stated 6.8... which is rather slow considering
that would equate to my average speeds in good air.
In 25 gusting to 35 that boat will sustain 6.8 easily even with a good chop
to weather.

Look John... these boats carry amazing momentum.... enough to reduce chop
to insignificant equations.

CM

there is a Nordica 30 owner right
here with a sister ship to mine that claims he has never gotten beyond 6
knots of speed from the vessel..

Some people are honest.
S/V Express 30 "Ringmaster"
"Trains are a winter sport"

Well you should remember that the Boobster told us he did 13kts in 8kts of wind
with his 70s era tub.


I'd sure like to see Loco-the-loser find THAT post!!!!

RB