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-   -   What do I lose by having a shorter boat? (https://www.boatbanter.com/touring/44847-what-do-i-lose-having-shorter-boat.html)

rick June 17th 05 12:40 AM


"Michael Daly" wrote in message
...
On 15-Jun-2005, "rick" wrote:

Again, how
does a longer kayak "overall" not have a longer waterline for
the same type hull


The original poster said nothing about "same type hulls." He
provided two overall lengths and asked for an assessment of
how the speed would compare. I correctly stated that one
cannot
determine that from the information on overall length.

But for a given
hull design, it still looks to me that that will be the major
factor according to the sites I posted.


You're ignoring the data on the graph. The data comes from
Sea Kayaker magazine and clearly shows that there is no
correlation between overall length and resistance. Why do
you keep insisting that there is?

====================
Beause you've failed to make your case against the other sites I
have read.



See also:
http://www.kayakforum.com/cgi-sys/cgiwrap/guille/wiki.pl?The_Myth_Of_Length

No, I'm posting web sites that state the opposite of you, not
MY
opinion. Which of course you have snipped.


Try reading a book on the hydrodynamics of hulls. C.A.
Marchaj's
"Sailing Theory and Practice" is a good one. You can also stop
assuming that overall length and waterline length are
interchangable.

I was seriously asking for data.


I gave you some. It shows that there is no correlation between
resistance and length for 24 common sea kayaks that have been
reviewed in Sea Kayaker magazine.

========================
No, you did not answer the question I asked. You snipped it out,
and ignored it. Why is that?



Mike




John Fereira June 17th 05 01:30 AM

"rick" wrote in
ink.net:


"Michael Daly" wrote in message
...
On 15-Jun-2005, "rick" wrote:

Again, how
does a longer kayak "overall" not have a longer waterline for the
same type hull


The original poster said nothing about "same type hulls." He
provided two overall lengths and asked for an assessment of
how the speed would compare. I correctly stated that one cannot
determine that from the information on overall length.

But for a given
hull design, it still looks to me that that will be the major factor
according to the sites I posted.


You're ignoring the data on the graph. The data comes from
Sea Kayaker magazine and clearly shows that there is no
correlation between overall length and resistance. Why do you keep
insisting that there is?

====================
Beause you've failed to make your case against the other sites I
have read.


Actually a very good case was made by posting information from a credible
source on sea kayak length.

Of the three sites you posted one was about Canoes from someone named Cliff
Jacobson. What are his credentials? The other two site specifically talk
about water line lenght, not overall length, a point that Mike has stressed
throughout this thread. The original poster asked for a speed comparison of
two kayaks of similar overall length, and Mike correctly pointed out that a
speed comparison can not be made based on overall length. In response you
post three sites, one about canoes and the other two which support Michaels
contentention that waterline length (not overall length) is an influencing
factor.




See also:
http://www.kayakforum.com/cgi-sys/cg...?The_Myth_Of_L
ength

No, I'm posting web sites that state the opposite of you, not
MY
opinion. Which of course you have snipped.


No, you posted two web sites which agreed with him.


Try reading a book on the hydrodynamics of hulls. C.A.
Marchaj's
"Sailing Theory and Practice" is a good one. You can also stop
assuming that overall length and waterline length are interchangable.

I was seriously asking for data.


I gave you some. It shows that there is no correlation between
resistance and length for 24 common sea kayaks that have been reviewed
in Sea Kayaker magazine.

========================
No, you did not answer the question I asked. You snipped it out,
and ignored it. Why is that?


I read back through the thread and the only question you asked was related
to canoes, not sea kayaks, which is what the original poster was aksing
about. While Michael didn't answer the question directly (or maybe just
hasn't given the answer you want to hear) he did answer it by posting the
comparison of overall length vs water line length for 24 sea kayaks. I
don't think anyone is going to deny that a kayak with a 18' overall length
is going to have a longer waterline than a kayak with a 14' overal length
but the original poster was asking about two boats with that much of a
difference in overall length. The differences in overall length in the
boats that the OP was asking about was only about a foot and a half and it
is entirely possible that the boat with the longer overall length would have
a shorter waterline length, or at least be close enough that the water line
length would have a negligable impact in kayak speed. That's the point
that Michael has been making all along but you seem more interested in just
arguing by tossing out red herrings that are irrelevant to was the OP was
asking.

rick June 17th 05 03:26 AM


"John Fereira" wrote in message
.. .
"rick" wrote in
ink.net:


"Michael Daly" wrote in message
...
On 15-Jun-2005, "rick" wrote:

Again, how
does a longer kayak "overall" not have a longer waterline
for the
same type hull

The original poster said nothing about "same type hulls." He
provided two overall lengths and asked for an assessment of
how the speed would compare. I correctly stated that one
cannot
determine that from the information on overall length.

But for a given
hull design, it still looks to me that that will be the
major factor
according to the sites I posted.

You're ignoring the data on the graph. The data comes from
Sea Kayaker magazine and clearly shows that there is no
correlation between overall length and resistance. Why do
you keep
insisting that there is?

====================
Beause you've failed to make your case against the other sites
I
have read.


Actually a very good case was made by posting information from
a credible
source on sea kayak length.

Of the three sites you posted one was about Canoes from someone
named Cliff
Jacobson. What are his credentials? The other two site
specifically talk
about water line lenght, not overall length, a point that Mike
has stressed
throughout this thread. The original poster asked for a speed
comparison of
two kayaks of similar overall length, and Mike correctly
pointed out that a
speed comparison can not be made based on overall length. In
response you
post three sites, one about canoes and the other two which
support Michaels
contentention that waterline length (not overall length) is an
influencing
factor.

=======================
I never claimed otherwise. He keeps asserting that overall
length is no indicator at all of waterline length. Most people
will recognise that typically the longer the boat, the longer the
waterline. In the discussion I was commenting on, he declared
length meant NOTHING to speed. He claimed 'many factors'
contribute to speed, but has yet to state what those are, even
after being asked. Again, I've never denied 'waterline' lenngth,
but going on about symantics doesn't prove anything.







See also:
http://www.kayakforum.com/cgi-sys/cg...?The_Myth_Of_L
ength

No, I'm posting web sites that state the opposite of you,
not
MY
opinion. Which of course you have snipped.


No, you posted two web sites which agreed with him.

=================
No, I don't think so. He claimed "many factors" affect speed,
but length wasn't one of them.





Try reading a book on the hydrodynamics of hulls. C.A.
Marchaj's
"Sailing Theory and Practice" is a good one. You can also
stop
assuming that overall length and waterline length are
interchangable.

I was seriously asking for data.

I gave you some. It shows that there is no correlation
between
resistance and length for 24 common sea kayaks that have been
reviewed
in Sea Kayaker magazine.

========================
No, you did not answer the question I asked. You snipped it
out,
and ignored it. Why is that?


I read back through the thread and the only question you asked
was related
to canoes, not sea kayaks, which is what the original poster
was aksing
about.

==========================
Boats are boats. Being covered on top has no relation.



While Michael didn't answer the question directly (or maybe
just
hasn't given the answer you want to hear) he did answer it by
posting the
comparison of overall length vs water line length for 24 sea
kayaks.

=====================
No, he ignored, and snipped out the direct question I asked, and
repeating assertion about length does not answer the question I
asked, which was what are the 'many factors', since length plays
no part, in the speed of a boat.


I
don't think anyone is going to deny that a kayak with a 18'
overall length
is going to have a longer waterline than a kayak with a 14'
overal length
but the original poster was asking about two boats with that
much of a
difference in overall length.

=======================
Looks like Mike did. He claimed that overall length did not
correlate to waterline lenght.


The differences in overall length in the
boats that the OP was asking about was only about a foot and a
half and it
is entirely possible that the boat with the longer overall
length would have
a shorter waterline length, or at least be close enough that
the water line
length would have a negligable impact in kayak speed. That's
the point
that Michael has been making all along but you seem more
interested in just
arguing by tossing out red herrings that are irrelevant to was
the OP was
asking.

==========================
No, you seem to be selectivly reading what you want. I have
asked him what other factors are involved, he has refused to
answer, and continues his symantics about 'length'.




donquijote1954 June 17th 05 03:41 AM

OK, I'll toss another question...

How much faster would be the Manitou (12'10" by 25") than the Drifter
(12'7" by 32.5")?

Tell me in percentage...


Michael Daly June 17th 05 06:22 AM


On 16-Jun-2005, "rick" wrote:

Beause you've failed to make your case against the other sites I
have read.


How about - the sites you identified are irrelevant to the discussion.
Just because they talk about waterline length means nothing in the
context of comparing waterline length and overall length.

No, you did not answer the question I asked. You snipped it out,
and ignored it. Why is that?


Probably because your line of questions is not contributing to the
discussion. You just want to nit-pik on trivia.

The _fact_ is that overall length is not a reasonable indicator
of kayak performance. Waterline length may be, other factors
being equal. If you can't deal with that, there's nothing I can
do about it.

Mike

Michael Daly June 17th 05 06:31 AM


On 16-Jun-2005, Peter wrote:

No, it clearly was never true. Even taking the subset of kayaks you
chose, you calculated a correlation coefficient of 0.79 indicating a
very high level of correlation.


Not high enough and nowhere near the level you claimed without any
proof.

The _fact_ is that at that level, the differences in overall length
between two kayaks are comparable to the differences in overall
length and waterline length in one kayak. Clearly a much higher
level of correlation is required than 0.79. In this case, the
mathematic definition of correlation has to take a back seat
to the more pragmatic need to produce information that is of
some value.


If all kayak types were included the
correlation would be even higher.


Your claim - how about something resembling proof? Your last
guess of 0.95 was based on nothing.

In the particular case of the two kayaks considered by the OP, their
lengths only differed by about 2' but the hull shapes appear to be quite
similar with no obvious difference in overhang. Therefore it's highly
likely that the Biscyne which is longer overall will also have a longer
waterline length.


Even if it does have a longer waterline length, that still does not
guarantee that the speed is higher. Hydrodynamics trumps simple
geometric parameters.

How about offering something of value instead of simply trying
to not-pick? Like offering some data that actually backs up you
ludicrous claim that what I am saying is false.

Mike

Michael Daly June 17th 05 06:35 AM


On 16-Jun-2005, "rick" wrote:

He claimed "many factors" affect speed,
but length wasn't one of them.


Where exactly have I ever said that waterline length doesn't
affect speed? I said that overall length is not a usable
indicator because of the great variation between overall
length and waterline length. I demonstrated that with
a scatter graph of the two parameters for _real_ sea kayaks.

Mike

Peter June 17th 05 06:42 AM

Michael Daly wrote:
Like offering some data that actually backs up you
ludicrous claim that what I am saying is false.


You already provided it yourself. After first making the claim that
there was "no correlation" between LOA and LWL, you later provided data
indicating that the correlation was 0.79 which clearly showed your
initial statement to be false. QED.


Michael Daly June 17th 05 06:52 AM


On 16-Jun-2005, "rick" wrote:

I
don't think anyone is going to deny that a kayak with a 18'
overall length
is going to have a longer waterline than a kayak with a 14'
overal length

=======================
Looks like Mike did. He claimed that overall length did not
correlate to waterline lenght.


Lookee, Lookee what I found on the web site that someone posted
with Sea Kayaker magazine data:

Prijon*Calabria Current Design Andromeda
LOA 4.42m (14.5ft) 5.26m (17.25ft)
LWL 3.96m (13 ft) 4.19m (13.75ft)
Drag 16.7 lb 18.0 lb

So here we have two _real_ sea kayaks, one that is more than 17 foot
long and another that is over 14 feet long (one 19% longer) yet
their waterline lengths are 13 and 13.75 feet respectively (one
only 6% longer).

Note in particular that the _shorter_ kayak has less resistance
at 4.5 knots.

Is this what you call a high correlation between LOA and LWL? Does
this prove that long kayaks are faster?

Mike

rick June 17th 05 11:20 AM


"Michael Daly" wrote in message
...

On 16-Jun-2005, "rick" wrote:

He claimed "many factors" affect speed,
but length wasn't one of them.


Where exactly have I ever said that waterline length doesn't
affect speed? I said that overall length is not a usable
indicator because of the great variation between overall
length and waterline length. I demonstrated that with
a scatter graph of the two parameters for _real_ sea kayaks.

Mike

======================
OK Not getting anywhere I see. You still won't/can't answer the
question I asked. Thanks anyway. I'll just wait or somebody
else, someday...





rick June 17th 05 11:22 AM


"Michael Daly" wrote in message
...

On 16-Jun-2005, "rick" wrote:

Beause you've failed to make your case against the other sites
I
have read.


How about - the sites you identified are irrelevant to the
discussion.
Just because they talk about waterline length means nothing in
the
context of comparing waterline length and overall length.

No, you did not answer the question I asked. You snipped it
out,
and ignored it. Why is that?


Probably because your line of questions is not contributing to
the
discussion. You just want to nit-pik on trivia.

====================
No I did not. I asked you to explain YOUR statement about the
"many factors" that affect speed other than length. You are the
one nit-picking on definitions.



The _fact_ is that overall length is not a reasonable indicator
of kayak performance. Waterline length may be, other factors
being equal. If you can't deal with that, there's nothing I
can
do about it.

=================
Obviously you can't. thanks anyway. I'll wait for somebody else
to explain all those other factors someday. Obviously you can't.



Mike




Bub June 17th 05 12:35 PM

I'm not sure what you mean by "Can the padding be removed from the seat?

I use a rudder if its windy,10 mph or more, otherwise no, don't need it.
I think you could get along in the Zoar with a skeg just as well.

"donquijote1954" wrote in message
oups.com...


Bub wrote:
Take a long look at the necky Zoar Sport. 14 foot boat w/rudder well

made
and stable. A little more boat then the Manitou. At $999 w/rudder, its

not
bad.
Bub



Thanks!

Two questions: Can the padding be removed from the seat? and, Do you
get to use the rudder/keg or is it a nuisance?

I'll quote something...

'The Zoar Sport is a brilliant little boat. At 14' it is a touring boat
rather than a true sea kayak but I have found with mine that: 1) it
handles very well on fla****er, keeping close to the longer, "faster"
boats; 2) it handles extremely well in surf (force five conditions); 3)
it is solid and durable; and above all 4) it is a comfortable fit (I am
6'4" 240 lbs). Great boat.'




Michael Daly June 17th 05 02:02 PM


On 17-Jun-2005, Peter wrote:

You already provided it yourself. After first making the claim that
there was "no correlation" between LOA and LWL, you later provided data
indicating that the correlation was 0.79 which clearly showed your
initial statement to be false. QED


I've already addressed that - the correlation is not sufficient to
allow for prediction of performance. You are ignoring that _fact_.

As a further indicator of the relevance of LOA as an indicator of
performance, let's look at the correlation between the lengths
and the drag for the kayaks already presented.

Correlation coefficient, LOA vs Drag: -0.35
Correlation coefficient, LWL vs Drag: -0.69

Clearly, an intelligent person would not use LOA as an indicator
of performance. This further shows that the correlation between
LOA and LWL is insufficiently high. It also shows that other
factors beyond just length dictate drag, otherwise the coefficient
for LWL vs drag would be higher.

For cranky ol' rick, I'll get to other factors later.

Mike

donquijote1954 June 17th 05 06:43 PM



Bub wrote:
I'm not sure what you mean by "Can the padding be removed from the seat?

I use a rudder if its windy,10 mph or more, otherwise no, don't need it.
I think you could get along in the Zoar with a skeg just as well.


Thanks. I thought the rudder/skeg may be unnecessary in a kayak of that
lenght.

I don't like any padding on the seat because of my peeing. Current
Designs, for example, doesn't have any.


donquijote1954 June 19th 05 03:54 AM

Well, settled, I've tried the Manitou and it's too small for me. Later
I tried a Tarpon 160 and found it very nice. It'll be my next boat.
THANKS ALL!!!

Best Wishes


donquijote1954 June 19th 05 05:02 PM



Frederick Burroughs wrote:
You could have a sharkskin textured slipover designed for your kayak,
similar to the swim wear worn by some athletes. In designer colors
and patterns, it is worn by your kayak to increase speed and get
envious stares.





--
"This president has destroyed the country, the economy,
the relationship with the rest of the world.
He's a monster in the White House. He should resign."

- Hunter S. Thompson, speaking to an antiwar audience in 2003.


I wouldn't do that. I mean if you are in favor of a democratic world
for sardines...

"The Forum for Losers.....for those who have no life."

I think we kayakers got more in common with sardines. Think about it:
WE ALWAYS ARE AT THE BOTTOM OF THE FOOD CHAIN. Yet you see too many
sharks around here. They must be trying to stop the little fish from
organizing.

Well, next time you see one of those fake kayakers out there with the
big teeth sticking out, say, "Hey PREDATOR, you are too big for a
kayak!"


Rick June 20th 05 05:25 AM

...stuff deleted

Lookee, Lookee what I found on the web site that someone posted
with Sea Kayaker magazine data:

Prijon Calabria Current Design Andromeda
LOA 4.42m (14.5ft) 5.26m (17.25ft)
LWL 3.96m (13 ft) 4.19m (13.75ft)
Drag 16.7 lb 18.0 lb

So here we have two _real_ sea kayaks, one that is more than 17 foot
long and another that is over 14 feet long (one 19% longer) yet
their waterline lengths are 13 and 13.75 feet respectively (one
only 6% longer).

Note in particular that the _shorter_ kayak has less resistance
at 4.5 knots.


Mike,

This is a pretty good comparison. I assume that the two boats were
unladen. Geared up for a long tour, however, the shorter boat should
ride deeper in the water (the LWL of the Andromeda should increase
significantly as the hull rides deeper), while the Calabria already has
most of its hull in the water. One would expect the drag to increase (as
well as the beam of the boat) as weight is added. I think this is where
we'd begin to see a performance hit on the shorter boat.

That is a heck of a lot of hull out of the water on the Andromeda,
however. Must be a real joy in wind (though probably pretty fun in surf
and waves).

Rick

Frederick Burroughs June 20th 05 04:27 PM

donquijote1954 wrote:


Frederick Burroughs wrote:

You could have a sharkskin textured slipover designed for your kayak,
similar to the swim wear worn by some athletes. In designer colors
and patterns, it is worn by your kayak to increase speed and get
envious stares.

I wouldn't do that. I mean if you are in favor of a democratic world
for sardines...

"The Forum for Losers.....for those who have no life."

I think we kayakers got more in common with sardines. Think about it:
WE ALWAYS ARE AT THE BOTTOM OF THE FOOD CHAIN. Yet you see too many
sharks around here. They must be trying to stop the little fish from
organizing.

Well, next time you see one of those fake kayakers out there with the
big teeth sticking out, say, "Hey PREDATOR, you are too big for a
kayak!"


The slipover is sharkskin "textured" which results in improved laminar
flow, and theoretically less drag. It is essentially hosiery to be
worn by the kayak. The fabric can display any design and color you
choose, great white, barracuda, guppy, gleeful pink or camouflage...
You can even choose a pattern of foam and broken styrofoam, to blend
in perfectly with many of today's rivers and beaches.





--
"This president has destroyed the country, the economy,
the relationship with the rest of the world.
He's a monster in the White House. He should resign."

- Hunter S. Thompson, speaking to an antiwar audience in 2003.


Michael Daly June 20th 05 06:31 PM


On 20-Jun-2005, Rick wrote:

Geared up for a long tour, however, the shorter boat should
ride deeper in the water (the LWL of the Andromeda should increase
significantly as the hull rides deeper), while the Calabria already has
most of its hull in the water.


Adding 50lb to each kayak only makes the difference in waterline lengths
change from 5.8% to 6.2% - not very much.

One would expect the drag to increase (as
well as the beam of the boat) as weight is added.


The Andromeda actual increases its wetted surface more.

That is a heck of a lot of hull out of the water on the Andromeda,
however. Must be a real joy in wind (though probably pretty fun in surf
and waves).


I have only paddled the Andromeda for an hour or so in moderate
conditions. It sucks. I can't say anything good about that
kayak... well, the colour was nice.

It's a Derek Hutchinson design. Folks familiar with my opinions on
his boat design "skills" will know that I'd expect the results the
kayak yeilded. When I talked to Mike Henderson of Current Designs
the year before the kayak was sold, he said the kayak in development
would be "long and fast" compared to the GulfStream. It is long
and slow - much slower than the Gulfstream. How slow? - there are
a whole whack of plastic and folding kayaks that are faster.

Mike

Grip June 22nd 05 03:32 AM

Never understood the "TRACKING"" thingy. If the paddler indeed knows how to
"paddle" any boat tracks well. White Water boats are made to spin on a dime,
but track as good as anything else if proper paddling strokes are used.
"donquijote1954" wrote in message
oups.com...
That's what I read too. The question is how a recreational boat would
be slower than a touring boat of the same lenght. I read a bottom that
makes for more initial stability also produces less speed. For example
the Biscayne at 14'6" was rated a mere 3 out of 5 in speed when it was
a Dagger Savannah...


http://www.dagger.com/product.asp?Bo...DC&BoatI D=13
5

Yet it's rated as fast by several reviewers...

"Just bought a Savannah Expedition model. Love it -- fast, stable,
tracks beautifully. Great fit for me. Paddle some rivers, some lakes,
some of Great Lakes. When I demo'd 5 other boats the Savannah was the
hands-down winner."

http://www.paddling.net/Reviews/show....html?prod=483




Cyli June 22nd 05 11:20 AM

On Tue, 21 Jun 2005 22:32:07 -0400, "Grip" wrote:

Never understood the "TRACKING"" thingy. If the paddler indeed knows how to
"paddle" any boat tracks well. White Water boats are made to spin on a dime,
but track as good as anything else if proper paddling strokes are used.



Yep. Loaned my buddy my recreational Old Town Otter one day while I
paddled my Perception Dancer. He was amazed at how I made it track
(and I'm not that good) compared to his friend who'd taken him out one
day to paddle ww kayaks on flat water. I explained that I rarely did
ww (none by choice any more) and had adapted to paddling flat. He
thought I had a different kayak bottom than his friend had. Nope. It
is harder to get used to paddling straight in a ww kayak, but not all
that bad. And it's great for current and eddy lines in flat rivers.
It's not quite as fast going downstream in one, but it's a bit faster
going upstream. For me. I'm slow either way. I like to dawdle along
slowly anyway.

The best part of a keel in flat rivers is that you can do a cross
current ferry with almost no paddling going downstream.

Cyli
r.bc: vixen. Minnow goddess. Speaker to squirrels.
Often taunted by trout. Almost entirely harmless.

http://www.visi.com/~cyli
email: lid (strip the .invalid to email)


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