"Wayne.B" wrote in message
news
On Tue, 28 Aug 2007 14:04:55 -0500, "KLC Lewis"
wrote:

This is one of those "Yes, but" things. Yes, you can go faster than hull
speed with enough power, but there is still a limit. And there's a point
at
which your rig simply can't stand up to that much power, and you are
dismasted. Surfing allows a boat to go much faster than hull speed, but
it's
also tricky and requires expert helmsmanship.

There are sail boats that will plane off at literally 2 and 3 times
theoretical hull speed, skimming along the top of the water. It's all
a function of weight, length, bottom shape, sail area, etc.

Sure there are -- but they aren't displacement hulls, either.

On Tue, 28 Aug 2007 19:44:11 -0500, "KLC Lewis"
wrote:

Sure there are -- but they aren't displacement hulls, either.

That gets you into a new discussion about what is a displacement hull.

I used to race on a boat called a B-29 that had a conventional lead
keel and a conventional spinnaker, a displacement hull to all
appearances. Sail area was a bit on the high side however, and on a
windy broad reach it could get onto plane and do 18 kts, about 3x hull
speed.

"Wayne.B" wrote in message
...
On Tue, 28 Aug 2007 19:44:11 -0500, "KLC Lewis"
wrote:

Sure there are -- but they aren't displacement hulls, either.

That gets you into a new discussion about what is a displacement hull.

I used to race on a boat called a B-29 that had a conventional lead
keel and a conventional spinnaker, a displacement hull to all
appearances. Sail area was a bit on the high side however, and on a
windy broad reach it could get onto plane and do 18 kts, about 3x hull
speed.

It strikes me that a boat that can get onto plane isn't a displacement hull,
all appearances aside. :-)

On Tue, 28 Aug 2007 20:34:28 -0500, in message

"KLC Lewis" wrote:


"Wayne.B" wrote in message
.. .
On Tue, 28 Aug 2007 19:44:11 -0500, "KLC Lewis"
wrote:

Sure there are -- but they aren't displacement hulls, either.

That gets you into a new discussion about what is a displacement hull.

I used to race on a boat called a B-29 that had a conventional lead
keel and a conventional spinnaker, a displacement hull to all
appearances. Sail area was a bit on the high side however, and on a
windy broad reach it could get onto plane and do 18 kts, about 3x hull
speed.

It strikes me that a boat that can get onto plane isn't a displacement hull,
all appearances aside. :-)

Yes that's true, if you define boats that significantly exceed 1.34
sqrt(LWL) out of the category. There are, however, lots of boats that
depend on a ballast keel for stability, that typically beat to weather
in displacement mode, and can still go through the water much more
quickly in the right conditions.

And going back to my original comment that sparked all this: The vast
majority of the sailboats I'm aware of do have a higher top speed
under sail than under power.

Ryk

On Tue, 28 Aug 2007 20:34:28 -0500, "KLC Lewis"
wrote:

I used to race on a boat called a B-29 that had a conventional lead
keel and a conventional spinnaker, a displacement hull to all
appearances. Sail area was a bit on the high side however, and on a
windy broad reach it could get onto plane and do 18 kts, about 3x hull
speed.

It strikes me that a boat that can get onto plane isn't a displacement hull,
all appearances aside. :-)

I understand your point but you can get almost any boat with a more or
less flat bottom to plane under the right conditions.

"KLC Lewis" wrote in
et:


"Wayne.B" wrote in message
news
On Tue, 28 Aug 2007 14:04:55 -0500, "KLC Lewis"
wrote:

This is one of those "Yes, but" things. Yes, you can go faster than
hull speed with enough power, but there is still a limit. And there's
a point at
which your rig simply can't stand up to that much power, and you are
dismasted. Surfing allows a boat to go much faster than hull speed,
but it's
also tricky and requires expert helmsmanship.

There are sail boats that will plane off at literally 2 and 3 times
theoretical hull speed, skimming along the top of the water. It's
all a function of weight, length, bottom shape, sail area, etc.

Sure there are -- but they aren't displacement hulls, either.




Depends on how many wakeboarders you're towing...(c;

http://www.youtube.com/watch?v=iLMOdhce-Pk

Of course, you can make up for the wakeboarders by only having one
pontoon in the water..without all that drag from rudders and
centerboards.

And, who says a monohull can't keep up with a multihull, anyways?
http://www.youtube.com/watch?v=iWWf1...elated&search=
I think the monohull is passing them!

Larry
--