Ole Thom is stupid and so are most of the rest of you
 

Play with this for a while and you will see that for the type of
upwind speeds the "Bat" has it needs higher aspect ratio sails.

http://www.wb-sails.fi/news/SailPowe...lPowerCalc.htm

CN

Thanks Neal,

Starting a new thread is a very good Idea. It probably is going to take
more time to educate you than I thought.
(By the way, I can't use JAVA)
Now, If I understand you, You are saying (Correct me if I'm wrong)
Aspect RATIO is Base (foot length) to Luff length.

Neal, I call that sail area. A longer Luff is a Taller Rig and that is a
fact. However, You are leaving out and important item. Lift; two sails
with the same foot and luff can have different "ASPECT RATIOS"
Do you agree to this?

This Stupid old man, says Aspect Ratio uses CHORD Depth and Position to
Horizontal distance of sail from Luff to Leech. In other words the
airfoil shape.

The fact is you even had it explained in one of your replies, About the
Pirate and the Horizontal swipe of the sail with his cutlass. Your
example; not mine (G)

Again, this stupid old man says it again;
You haven't a clue!!
When you straighten me out on that, we'll go farther with your
enlightenment.

Ole Thom

Wow Neal,

You've got 3 threads going. Which one do you want to use to prove I'm
STUPID?

Since you agreed to what Aspect Ratio was in "Wild Ride" although you
referred to height and base, in one of the treads as Sail Aspect Ratio.

Aspect Ratio
Do we agree that the deeper the Chord the Higher the Aspect Ratio? This
is important because if you do, high aspect sails aren't faster, they
are slower.

They are more powerful. That is they will DRAW when the wind is light.
Similar to 1st gear on a transmission, but need to be flat (Low Aspect)
for high speeds.

Think about that for awhile, before we continue on about Sail Aspect
Ratio.

Ole Thom

I'll add (nothing useful) to this multi-thread by commenting that The
Crapton's math/physics knowledge is matched only by his sailing skill.
Frank (IOW, zero = zero)

Thom,

You are being overly simplistic. Since sails are not rectangles the chord is not
a fixed quantity. The chord can be viewed as an average at best.

For example, it the foot of the sail is ten feet and the luff of the sail is 30 feet
then one could say the aspect ratio is 3:1. However since the sail is not a rectangle
this aspect ratio does not give the complete picture. There is a different aspect ratio
depending on where the chord measurement is taken along the luff and leech of the sail.

But, putting all this aside, a sail with a foot of ten feet will have a lower aspect
ratio than a sail with a foot of eight feet given the luff of both sails is the same
and each has approximately the same roach.

It is clear to me that you don't understand what chord means. It has nothing to
do with the depth of the sail. It has to do with the width of the sail.

I hope this helps.

CN


"Thom Stewart" wrote in message ...
Wow Neal,

You've got 3 threads going. Which one do you want to use to prove I'm
STUPID?

Since you agreed to what Aspect Ratio was in "Wild Ride" although you
referred to height and base, in one of the treads as Sail Aspect Ratio.

Aspect Ratio
Do we agree that the deeper the Chord the Higher the Aspect Ratio? This
is important because if you do, high aspect sails aren't faster, they
are slower.

They are more powerful. That is they will DRAW when the wind is light.
Similar to 1st gear on a transmission, but need to be flat (Low Aspect)
for high speeds.

Think about that for awhile, before we continue on about Sail Aspect
Ratio.

Ole Thom

Neal,

Be very careful of what you're saying! Your last post is in error. You
may want to retract. You're not thinking, you're trying to double-talk
wrong statements.

I'm being simplistic by choose. I'm trying to make statement hopefully,
that can be used with double meaning.

When a sailmaker designs and makes a sail to a certain ASPECT SAIL
RATIO, he isn't working to an average. He is cutting and stitching to
fixed measurements. Even your Hong Kong short cutters. That statement
you've made is incorrect, Wrong !

Chord has everything to do with depth of Sail. Wrong again!

This discussion was created by your lack of a Clue about Sail Aspect
RATIO. I've been giving you true knowledge and yet you are still making
stupid, wrong statements.

A sailmaker can make a sail with the same foot length and Luff length
and have a Different Sail Ratio. He can make a sail with a smaller foot
have the same ASPECT RATIO. It depends on the RATIO of the depth (Chord)
to the length of the horizontal measurement from the Luff to the Leech.
THE RATIO!!!

I'm sure that a very large majority understand Aspect Ratio and you
still don't.

You've been caught, filet and made into roll mops. And; that from the
stupid, old man's doing.

Now let's talk about "Spitfires" sail plan.
Can you figure why they have what they have and why? That should be an
interesting reply.

I say again. Depth has nothing to do with chord. Chord is the measurement
of a sail parallel to the flow of the air. Depth has to do with the fullness
of flatness of a sail.

How is it you ever lived to be 120 years old without learning the basics?

CN



"Thom Stewart" wrote in message ...
Neal,

Be very careful of what you're saying! Your last post is in error. You
may want to retract. You're not thinking, you're trying to double-talk
wrong statements.

I'm being simplistic by choose. I'm trying to make statement hopefully,
that can be used with double meaning.

When a sailmaker designs and makes a sail to a certain ASPECT SAIL
RATIO, he isn't working to an average. He is cutting and stitching to
fixed measurements. Even your Hong Kong short cutters. That statement
you've made is incorrect, Wrong !

Chord has everything to do with depth of Sail. Wrong again!

This discussion was created by your lack of a Clue about Sail Aspect
RATIO. I've been giving you true knowledge and yet you are still making
stupid, wrong statements.

A sailmaker can make a sail with the same foot length and Luff length
and have a Different Sail Ratio. He can make a sail with a smaller foot
have the same ASPECT RATIO. It depends on the RATIO of the depth (Chord)
to the length of the horizontal measurement from the Luff to the Leech.
THE RATIO!!!

I'm sure that a very large majority understand Aspect Ratio and you
still don't.

You've been caught, filet and made into roll mops. And; that from the
stupid, old man's doing.

Now let's talk about "Spitfires" sail plan.
Can you figure why they have what they have and why? That should be an
interesting reply.

http://www.seed.slb.com/en/scictr/watch/sailing/

I hope this helps. It shows a picture of what chord is and it mentions the term
chord depth. You have obviously confused depth with chord.

CN


"Thom Stewart" wrote in message ...
Neal,

Be very careful of what you're saying! Your last post is in error. You
may want to retract. You're not thinking, you're trying to double-talk
wrong statements.

I'm being simplistic by choose. I'm trying to make statement hopefully,
that can be used with double meaning.

When a sailmaker designs and makes a sail to a certain ASPECT SAIL
RATIO, he isn't working to an average. He is cutting and stitching to
fixed measurements. Even your Hong Kong short cutters. That statement
you've made is incorrect, Wrong !

Chord has everything to do with depth of Sail. Wrong again!

This discussion was created by your lack of a Clue about Sail Aspect
RATIO. I've been giving you true knowledge and yet you are still making
stupid, wrong statements.

A sailmaker can make a sail with the same foot length and Luff length
and have a Different Sail Ratio. He can make a sail with a smaller foot
have the same ASPECT RATIO. It depends on the RATIO of the depth (Chord)
to the length of the horizontal measurement from the Luff to the Leech.
THE RATIO!!!

I'm sure that a very large majority understand Aspect Ratio and you
still don't.

You've been caught, filet and made into roll mops. And; that from the
stupid, old man's doing.

Now let's talk about "Spitfires" sail plan.
Can you figure why they have what they have and why? That should be an
interesting reply.

"Thom Stewart" wrote in message ...
Now let's talk about "Spitfires" sail plan.
Can you figure why they have what they have and why? That should be an
interesting reply.


What they have is sails not suited to the task at hand which task is breaking speed
records. To go faster they need higher aspect ratio sails with a more rounded top to
reduce drag caused by the tip vortex those flat-topped sails create.

CN

Capt. Neal® wrote in message
...
What they have is sails not suited to the task at hand which task is
breaking speed
records. To go faster they need higher aspect ratio sails with a more
rounded top to
reduce drag caused by the tip vortex those flat-topped sails create.

CN

How do you explain why a glider (no engine, slow speed)
has wings with much higher aspect ratio than a jet fighter...?

A jet fighter uses massive horsepower to stay in the air. It only needs short, stubby wings
because it operates at very high speeds.

A sailboat operates at far lower speeds and so does the glider. The question you
asked merely confirms the fact that the catamaran should have sails shaped more
like those of a glider than those of a jet fighter.

CN


"Edgar" wrote in message ...

Capt. Neal® wrote in message
...
What they have is sails not suited to the task at hand which task is
breaking speed
records. To go faster they need higher aspect ratio sails with a more
rounded top to
reduce drag caused by the tip vortex those flat-topped sails create.

CN

How do you explain why a glider (no engine, slow speed)
has wings with much higher aspect ratio than a jet fighter...?

Crapt. Neal® wrote:
... To go faster they need higher aspect ratio sails with a more rounded
top to
reduce drag caused by the tip vortex those flat-topped sails create.


So, a foil with a rounded or pointy tip doesn't cause a tip vortex?

Where's Jax when you need him?

DSK

There will always be a tip vortex. However, a longer foil with shorter chord
tapering to a more rounded or pointed end will create a smaller vortex with
less subsequent drag than a sail that is flat on the end like the ones shown
in the picture.

CN


"DSK" wrote in message .. .
Crapt. Neal® wrote:
... To go faster they need higher aspect ratio sails with a more rounded
top to
reduce drag caused by the tip vortex those flat-topped sails create.


So, a foil with a rounded or pointy tip doesn't cause a tip vortex?

Where's Jax when you need him?

DSK

Capt. Neal® wrote in message
...
A jet fighter uses massive horsepower to stay in the air. It only needs
short, stubby wings
because it operates at very high speeds.

A sailboat operates at far lower speeds and so does the glider. The
question you
asked merely confirms the fact that the catamaran should have sails shaped
more
like those of a glider than those of a jet fighter.

CN


"Edgar" wrote in message
...
How do you explain why a glider (no engine, slow speed)
has wings with much higher aspect ratio than a jet fighter...?

This is where you are wrong. The contraption we are talking about is not a
catamaran but a hydrofoil. The only thing it is any good for is a blast
along a broad reach foilborne. If you tried to sail the thing close to the
wind it would lose so much speed it would drop off its foils and just wallow
about waiting for the helmsman to bear away and get up some speed again.
Hence it is pointless to give it high aspect sails which would increase
efficiency to windward in a normal catamaran.
All it requires is brute force from the sails on a broad reach and minimum
heeling moment. Hence they went for a lot of sail on a low aspect ratio
rig.

Crapton,

You're blowing smoke. Spitfire doesn't give a damn about slow speed
sailing. It is interested in the very upper end of sailing speed.

That is the reason for the choice of "Low Aspect" sails. Larger sail
area with less heeling moment. Burying a Foil to heeling would kill
speed faster than "Air Vortex"
They increased SAIL AREA without increasing Heeling Force by adding a
SECOND SAIL without increasing HEELING FORCE.

Two sails: Increasing driving force of the wind without increasing the
Winds leverage for heeling. This increase of the second sail, off to the
side rather than a Ketch Rig, made the Multi Hull necessary. This had
the advantage of adding Hydrofoils at a wider angle. Increasing speed is
made possible by sailing flat, using LOW ASPECT SAILS without the need
to carry a Heavy Weighted Keel to overcome the Heeling Force created by
a TALL MAST carrying HIGH ASPECT SAIL (Sail with a larger curve)

That, my friend, ends my attempt to ENLIGHTEN you. Open your mind and
learn

Lesson over, filleting complete.

Ole Thom

Doug,

Don't Know? We created a round hydrofoil but can't get any lift out of
it (G)
I'll check to see what I'm doing wrong with the Crapton (LOL)

Ole Thom

You're all wrong! The Spitfire has a high aspect rig. Here's another
pictu

http://wingsail.neuralfuzz.com/wingsaildesigns.htm

By having two sails the center of effort is kept low, but the efficiency
of the sails stays high.

Thom Stewart wrote:
Crapton,

You're blowing smoke. Spitfire doesn't give a damn about slow speed
sailing. It is interested in the very upper end of sailing speed.

That is the reason for the choice of "Low Aspect" sails. Larger sail
area with less heeling moment. Burying a Foil to heeling would kill
speed faster than "Air Vortex"
They increased SAIL AREA without increasing Heeling Force by adding a
SECOND SAIL without increasing HEELING FORCE.

Two sails: Increasing driving force of the wind without increasing the
Winds leverage for heeling. This increase of the second sail, off to the
side rather than a Ketch Rig, made the Multi Hull necessary. This had
the advantage of adding Hydrofoils at a wider angle. Increasing speed is
made possible by sailing flat, using LOW ASPECT SAILS without the need
to carry a Heavy Weighted Keel to overcome the Heeling Force created by
a TALL MAST carrying HIGH ASPECT SAIL (Sail with a larger curve)

That, my friend, ends my attempt to ENLIGHTEN you. Open your mind and
learn

Lesson over, filleting complete.

Ole Thom

They need to be *higher* aspect ratio than that.

CN


"Jeff Morris" wrote in message ...
You're all wrong! The Spitfire has a high aspect rig. Here's another
pictu

http://wingsail.neuralfuzz.com/wingsaildesigns.htm

By having two sails the center of effort is kept low, but the efficiency
of the sails stays high.

Thom Stewart wrote:
Crapton,

You're blowing smoke. Spitfire doesn't give a damn about slow speed
sailing. It is interested in the very upper end of sailing speed.

That is the reason for the choice of "Low Aspect" sails. Larger sail
area with less heeling moment. Burying a Foil to heeling would kill
speed faster than "Air Vortex"
They increased SAIL AREA without increasing Heeling Force by adding a
SECOND SAIL without increasing HEELING FORCE.

Two sails: Increasing driving force of the wind without increasing the
Winds leverage for heeling. This increase of the second sail, off to the
side rather than a Ketch Rig, made the Multi Hull necessary. This had
the advantage of adding Hydrofoils at a wider angle. Increasing speed is
made possible by sailing flat, using LOW ASPECT SAILS without the need
to carry a Heavy Weighted Keel to overcome the Heeling Force created by
a TALL MAST carrying HIGH ASPECT SAIL (Sail with a larger curve)

That, my friend, ends my attempt to ENLIGHTEN you. Open your mind and
learn

Lesson over, filleting complete.

Ole Thom

Jeff,

I stand corrected on the sails. What is the Aspect Ratio number? I
thought it would be a rather "Low" number for the speeds she was
attaining.

Ole Thom

Thom Stewart wrote:
Jeff,

I stand corrected on the sails. What is the Aspect Ratio number? I
thought it would be a rather "Low" number for the speeds she was
attaining.

Ole Thom

I haven't found the specs for the boat, but the line drawings show the
aspect ration to be over 3 to 1. Plus, with the square top, the
effective ratio is much higher. Think of it as simply removing the top
quarter of a sail - the part that generates little lift but contributes
heeling moment. Add to that the fact that the sails are actually wing
sails, with two layers of cloth over a rotating mast, and internal
battens adjusting curvature ... I'm sure they have just the lift to drag
ratio the designers want for the boat. Its hard to argue with 45 knots.

Jeff,

I may be wrong but I do believe you're making the same error Neal is?
Aspect Sail Ratio is Chord distance compared to distance from luff to
leech measured horizontally. I don't understand how you're getting that
from the line drawing?

I can't e-mail you but you can use my addy to reply off line if you'd
like?

Ole Thom

Thom Stewart wrote:
Jeff,

I may be wrong but I do believe you're making the same error Neal is?
Aspect Sail Ratio is Chord distance compared to distance from luff to
leech measured horizontally. I don't understand how you're getting that
from the line drawing?

I can't e-mail you but you can use my addy to reply off line if you'd
like?

Ole Thom


Sorry Thom, the aspect ratio of a sail, as used by sailors, is the luff
to foot ratio. More properly, however, its the height squared divided
by the sail area. This number will be half what is normally given for a
triangular sail, but then increases as the roach is increased.

The wing sail of Spitfire has a luff to foot ratio of over 3 to 1, but
since it is nearly rectangular, its effective aspect ratio is much
higher than that of a triangular sail.

Is it possible you're thinking of the Camber Ratio, the depth of the
maximum draft over the luff to leech length?

Wow,
Just had a Hell-a-ish power dip (outage) lost the whole reply I was
writing to you Jeff, I'll try again

Jeff I was taught that mast height and boom length were used in " Rig
aspect ratio" & Chord (Chamber) & horizontal distance from Luff to Leech
were used to rate "Sail Aspect Ratio"

The reason I was given, so I wouldn't forget was; You can change Sail
Ratio on the Same Rig Ratio.

It may be Semantics. How 'bout we get some comments from the group. I'd
be interested in Doug's thoughts, We know Neal's but let him fire-away.

Ole Thom

While we are on the subject;

What are the advantages of the gaff rig and the advantages of the
Marconi?

The gaff is the better shaped sail for delivering force from the wind
but the disadvantage is the gaff, which provides excess weight aloft. It
also give more driving force with less heeling

The Marconi has less weight aloft because of no gaff but needs to go up
higher to control the shape of the working part of the sail. This extra
height increases heeling force

When we figure Rig Ratio the marconi will always be a "Higher Ratio" rig
by the nature of its shape.

A Gaff will always have a "Lower Ratio" rig because of the Gaff, around
3/4 to 2 /1 due to the shape, As efficent as the marconi but by
necessity has to be kept low because of the weight of the gaff.

Now on "Spitfire" they increased the height by using battens instead off
a gaff boom to decrease the heeling force and added another sail abaft
the other mast.

A much more efficent set-up with less heeling pressure.

Good Nite,
Ole Thom

Thom Stewart wrote:
While we are on the subject;

What are the advantages of the gaff rig and the advantages of the
Marconi?

The gaff is the better shaped sail for delivering force from the wind
but the disadvantage is the gaff, which provides excess weight aloft. It
also give more driving force with less heeling

The gaff also exerts less stress on the hull, and when you want to take
it down, it comes down easily & quickly. One of the disadvantages is
that the gaff tends to twist more.


The Marconi has less weight aloft because of no gaff but needs to go up
higher to control the shape of the working part of the sail. This extra
height increases heeling force

When we figure Rig Ratio the marconi will always be a "Higher Ratio" rig
by the nature of its shape.

A Gaff will always have a "Lower Ratio" rig because of the Gaff, around
3/4 to 2 /1 due to the shape, As efficent as the marconi but by
necessity has to be kept low because of the weight of the gaff.

Oh, I dunno, there are some pretty low aspect marconi rigs around...
some are called "leg o' mutton" rigs... and some high aspect gaffers.
L.Francis Herreshoff designed a number of relatively high aspect gaff
rigs, with short single-halyard gaffs.



Now on "Spitfire" they increased the height by using battens instead off
a gaff boom to decrease the heeling force and added another sail abaft
the other mast.

A much more efficent set-up with less heeling pressure.

The modern sails with the top two or three battens full-length and the
lower battens short is a nice practical & efficient sail.

Fresh Breezes- Doug King

"Thom Stewart" wrote

Now on "Spitfire" they increased the height by using battens instead off
a gaff boom to decrease the heeling force and added another sail abaft
the other mast.

Sorry old chap, but on a tandem rig one mast is not abaft the other.
They are side by side.

As for battens increasing the height of the sails, you gotta be kidding.
The purpose of battens is to shape and flatten the sail and to
facilitate less twist in the leech.

CN

What ever, you are correct Neal.
Would "Two Mast, Broad Abeam" be better?

Ole Thom

Neal,

The upper battens on "SPITFIRE" go upward. You are right in that they
reduce twist. In this case Twist to the horizontal.

Neal, I sail full battens and I can induce twist as well as you can and
keep the Roach section in shape as it twists.

That is what battens are for, to maintain sail shape.

Hope its warm by you. To cold here to get the aroma of a good fart.

Ole Thom