Jib size or Main/Foretriangle Ratio
 

*** Jib size or Main/Foretriangle Ratio ***

If very theoretically 1 (equally large) must be the best. It lowers
(vertically) the CE to minimum and the shortest possible mast is needed.

1. What says that the main should be bigger?

2.Some boats have M/F-ratios of 4. That seems really stupid.

3. Is a self tacking jib a matter of importance when regarding the
M/F-ratio?



Morgan O.

Morgan O says:

1. What says that the main should be bigger?

Nothing really, but it has been found over many years that you are able to
"change gears" more efficiently this way. Reef main first, then drop a size of
headsail, then reef main again, then remove headsail completely, then reef main
again, then bare-pole in the least dangerous direction ;-) With a really
large jib, your first "gear change" involves removing the largest sail on the
boat.

2.Some boats have M/F-ratios of 4. That seems really stupid.

From someone who obviously has little knowledge of sailplans, why do you use
the word "stupid?" Do you really mean "I don't understand?"

3. Is a self tacking jib a matter of importance when regarding the
M/F-ratio?

Not necessarily

I suggest you find a book called "Sail Power", by Wally Ross, and look into
these things deeper.

Steve
Stephen C. Baker - Yacht Designer
http://members.aol.com/SailDesign/pr...cbweb/home.htm

On 14 Oct 2004 10:06:15 GMT, Stephen Baker wrote:

Morgan O says:

1. What says that the main should be bigger?

Nothing really, but it has been found over many years that you are able to
"change gears" more efficiently this way. Reef main first, then drop a size of
headsail, then reef main again, then remove headsail completely, then reef main
again, then bare-pole in the least dangerous direction ;-) With a really
large jib, your first "gear change" involves removing the largest sail on the
boat.

2.Some boats have M/F-ratios of 4. That seems really stupid.

From someone who obviously has little knowledge of sailplans, why do you use
the word "stupid?" Do you really mean "I don't understand?"

;o) ...that's one wya to see it.

I have dwelled over different riggs quite a while... and the real benefit of
a Bermuda Sloop is that you get 2 high ratio sails still with a low
positioned CE.

Making a small jib you could just as well use a Bermuda Cat (no jib).


3. Is a self tacking jib a matter of importance when regarding the
M/F-ratio?

Not necessarily

I get a little tiered of those who call themselves designers and only whant
people to buy books or get stuffed...

Usenet is for debateing facts, knowledge and gossip, and to those who
don't like that, try stopping it!

But it's probably true, if everyone, always, only threw book titels at each
other it would most likely die fast enough.


Morgan O.

On 14 Oct 2004 10:06:15 GMT, ospam (Stephen Baker)
wrote:

I suggest you find a book called "Sail Power", by Wally Ross, and look into
these things deeper.

Damn, I was lucky the day I found a used copy of that book! Was there
ever a sequel, second edition or more recent book that matches it for
clarity and sheer depth?

I totally rethought my sail trim due to Ross's work, and now get a lot
more out of my cruising.

R.

There are 35 copies available on alibris.com, from $6.75
A good book.

rhys wrote:

On 14 Oct 2004 10:06:15 GMT, ospam (Stephen Baker)
wrote:

I suggest you find a book called "Sail Power", by Wally Ross, and look into
these things deeper.

Damn, I was lucky the day I found a used copy of that book! Was there
ever a sequel, second edition or more recent book that matches it for
clarity and sheer depth?

I totally rethought my sail trim due to Ross's work, and now get a lot
more out of my cruising.

R.

Morgan Ohlson wrote:
I have dwelled over different riggs quite a while... and the real benefit of
a Bermuda Sloop is that you get 2 high ratio sails still with a low
positioned CE.

???

The higher the aspect ratio of the sails, the higher the CE.

However, a higher CE is not really a problem on a small crew-ballasted
boat. The difference is trivial. OTOH, high aspect ratio rigs have a
number of drawbacks for small boats... they require a bit more fancy
engineering, a somewhat more complex & more stressed rig, and they don't
work as well in light air. Then in heavy air, you reef and pay a penalty
in windage for the length of unused spar.


Making a small jib you could just as well use a Bermuda Cat (no jib).

Not necessarily. A small jib is helpful in several ways, including going
to windward, handling the boat in a chop, and helping the boat maneuver.




3. Is a self tacking jib a matter of importance when regarding the
M/F-ratio?

Not necessarily


I get a little tiered of those who call themselves designers and only whant
people to buy books or get stuffed...

???


Usenet is for debateing facts, knowledge and gossip, and to those who
don't like that, try stopping it!

Morgan, you're in the position of asking for free advice, and getting
huffy because you don't like what you're told. Seems to me you're still
coming out ahead in any cost/benefit analysis here... why the attitude?

FWIW I don't like self tacking jibs except on racing boats where you're
likely to be very busy with other more important tasks. Self tacking
adds rigging & clutter that a cruiser would probably be better off
without. Plus, no self tacking sheeting arrangement sheets the sail
effectively for a wide range of courses, for example you can have it set
up for going cloe-hauled (the most common arrangement) and it's all but
useless on a reach... when a racing boat would be setting a spinnaker
anyway, but you probably wouldn't be.

Fresh Breezes- Doug King

On Thu, 14 Oct 2004 12:53:59 -0400, DSK wrote:

Morgan Ohlson wrote:
I have dwelled over different riggs quite a while... and the real benefit of
a Bermuda Sloop is that you get 2 high ratio sails still with a low
positioned CE.

???

The higher the aspect ratio of the sails, the higher the CE.

Naturally, but CE fall when dividing the total area on two sails. The
minimum CE is when M/F = 1

.... I think....

If a Gaff sloop is compared to a Bermuda Sloop they will have almost the
same low CE if the Bermuda have M/F = 1 (Gaff generally considered to
have a very low CE)


/.../
OTOH, high aspect ratio rigs have a
number of drawbacks for small boats... they require a bit more fancy
engineering,

???


a somewhat more complex & more stressed rig,

Taller mast???
CG rais???


and they don't
work as well in light air.

Transformed CE hight into more area is preferred in lite air??? (Typical low
ratio Gaff)


Then in heavy air, you reef and pay a penalty
in windage for the length of unused spar.

A bermuda M/F = 1 keeps the CE as low as possible (for that type) and keeps
the mast as low as possible.

What wou write is definitely right, but your quick jumps doesn't make sense.
No rig can be optimized for all occations anyway. What can be done is to
avoid silly arrangements with the rig choosen.

A Bermuda Sloop, and basicly all sloops should have a M/F ~1 since
everything else fast incease other backsides.


Making a small jib you could just as well use a Bermuda Cat (no jib).

Not necessarily. A small jib is helpful in several ways, including going
to windward, handling the boat in a chop, and helping the boat maneuver.

Explain how a very small jib will improve on a decreased Cat. (same total
area and both correctly balanced to CLA)

The cat...
- can have a high (acceptable high) ratio too.
- is easier to handle.
- Less rigging.
- CG fall almost zero thanks to a small jib

The small jib will not motivate it's existence (work etc.) compared to a Cat
incl. the jib area.

/.../
FWIW I don't like self tacking jibs except on racing boats where you're
likely to be very busy with other more important tasks. Self tacking
adds rigging & clutter that a cruiser would probably be better off
without. Plus, no self tacking sheeting arrangement sheets the sail
effectively for a wide range of courses, for example you can have it set
up for going cloe-hauled (the most common arrangement) and it's all but
useless on a reach... when a racing boat would be setting a spinnaker
anyway, but you probably wouldn't be.

"going cloe-hauled (the most common arrangement)" ? sorry, don't
understand.

A self tacking boom arrangement attract me most. Someone called it "old
Petrus boom".


Morgan O.

Morgan O says:

I get a little tiered of those who call themselves designers and only whant
people to buy books or get stuffed...

If you'd like to pay the $50 per hour consultation fee that I usually charge
(and get), then I would be happy to entertain all your questions at great
length ;-)
However, if you are looking for free-ish info, then the book is as good as it
gets.

Steve "gives small freebies, but has to make a living..."
Stephen C. Baker - Yacht Designer
http://members.aol.com/SailDesign/pr...cbweb/home.htm

Morgan O says:

The
minimum CE is when M/F = 1

Actually, geometrically speaking, it doesn't matter what the Main/Foretriangle
ratio is - the CE is always at 1/3 of the height of the triangle. THis works
for catboats and genoa-only boats.

Steve

Morgan Ohlson wrote:
Naturally, but CE fall when dividing the total area on two sails. The
minimum CE is when M/F = 1

... I think....

No, you could make the foot much longer than the luff... if you
wanted... and that would have a marginally lower CE. It would look
rather strange though.



If a Gaff sloop is compared to a Bermuda Sloop they will have almost the
same low CE if the Bermuda have M/F = 1 (Gaff generally considered to
have a very low CE)

Yes, but some gaff sails have a higher aspect ratio than that.


/.../

OTOH, high aspect ratio rigs have a
number of drawbacks for small boats... they require a bit more fancy
engineering,


???

In order to gain any benefits from the higher aspect ratio, the sail has
to be more carefully designed & made, the mast has to be longer & shaped
for less turbulence over the forward part of the sail, etc etc. A high
aspect ratio sail is a (relatively) high tech tool. You did not see high
aspect ratio sails back in the old days because they did not have the
engineering nore the materials to make them stand and get the benefit.


a somewhat more complex & more stressed rig,


Taller mast???
CG rais???

Yes but there will also be more compression on the mast, more tension on
the shrouds, greater loads on all parts of the rig. Greater loads on the
hull too including heeling moment.


What wou write is definitely right, but your quick jumps doesn't make sense.

OK, that's why I'm back trying to explain a little better. I am not a
good explainer, sorry.

No rig can be optimized for all occations anyway. What can be done is to
avoid silly arrangements with the rig choosen.

Yes, that is very true.


A Bermuda Sloop, and basicly all sloops should have a M/F ~1 since
everything else fast incease other backsides.

That depends on your goals. A lot of very practical sloops seem to to
have a luff/foot of about 1.5 ~ 1.8 sometimes more. Of course there are
those with shorter rigs & longer booms, many of them sail well too. It's
a question of getting the right sail area, the right foils, and putting
them in the right place on the hull.




Making a small jib you could just as well use a Bermuda Cat (no jib).

Not necessarily. A small jib is helpful in several ways, including going
to windward, handling the boat in a chop, and helping the boat maneuver.


Explain how a very small jib will improve on a decreased Cat. (same total
area and both correctly balanced to CLA)

Why insist on keeping area constant? Are you designing your boat to a
rating rule? It's true that as the jib gets smaller relative to the
mainsail, the overall rig efficiency... in most conditions... tends to
go down. So you make the whole rig a little bigger.

My point is that jib can help very much under some conditions (for
example, helping the flow across the lee side of the lower portion of a
low aspect mainsail), it's handy for maneuvering, it looks nice, and it
helps stave off boredom. It does add to the cost though.



FWIW I don't like self tacking jibs except on racing boats where you're
likely to be very busy with other more important tasks. Self tacking
adds rigging & clutter that a cruiser would probably be better off
without. Plus, no self tacking sheeting arrangement sheets the sail
effectively for a wide range of courses, for example you can have it set
up for going cloe-hauled (the most common arrangement) and it's all but
useless on a reach... when a racing boat would be setting a spinnaker
anyway, but you probably wouldn't be.


"going cloe-hauled (the most common arrangement)" ? sorry, don't
understand.

If you set up the self-tacking jib so that it can be trimmed to be most
effective when close hauled, it will not be anywhere near as effective
on other points of sail. This doesn't seem to bother some people.


A self tacking boom arrangement attract me most. Someone called it "old
Petrus boom".

Never heard of that. Anyway, I hope this helps.

DSK

A Bermuda Sloop, and basicly all sloops should have a M/F ~1 since
everything else fast incease other backsides.

actually old photos of Bermuda Sloop rigs show a very long boom and a small
curved gaff at the top of the mainsail.

the tall narrow sloop rig is usually referred to as a Marconi rig, after the
early radio transmission towers held up by stays which the sailing rig
emulated.



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On 14 Oct 2004 21:34:36 GMT, Stephen Baker wrote:

Morgan O says:

The
minimum CE is when M/F = 1

Actually, geometrically speaking, it doesn't matter what the Main/Foretriangle
ratio is - the CE is always at 1/3 of the height of the triangle. THis works
for catboats and genoa-only boats.

Steve

Perhaps I make a misstake, but two equally high sails must make the bigghest
area AND much lower CE compared to a Cat rig

So, without checking it all that in detail I say you spread a misconception.

The CE gets LOWER with M/F=1 compared to the extreme M/F = 10/0 = eternity

Sails with the same aspect ratio understould.


Morgan O.

On Thu, 14 Oct 2004 17:38:06 -0400, DSK wrote:

Morgan Ohlson wrote:
OTOH, high aspect ratio rigs have a
number of drawbacks for small boats... they require a bit more fancy
engineering,


???

In order to gain any benefits from the higher aspect ratio, the sail has
to be more carefully designed & made, the mast has to be longer

Naturally ;o)

& shaped
for less turbulence over the forward part of the sail, etc etc. A high
aspect ratio sail is a (relatively) high tech tool. You did not see high
aspect ratio sails back in the old days because they did not have the
engineering nore the materials to make them stand and get the benefit.

When saying that you should state at which level you mean this becomes
nesessary.

Aspect Ratio? 3? 4? or 6?

A good aerodynamic rig is always a pleasure, but at which levels doesn't the
"old solutions" work at all?


a somewhat more complex & more stressed rig,


Taller mast???
CG rais???

Yes but there will also be more compression on the mast, more tension on
the shrouds, greater loads on all parts of the rig. Greater loads on the
hull too including heeling moment.

ABermuda sloop with M/F = 1 has the lowes mast per m2


What wou write is definitely right, but your quick jumps doesn't make sense.

OK, that's why I'm back trying to explain a little better. I am not a
good explainer, sorry.

No rig can be optimized for all occations anyway. What can be done is to
avoid silly arrangements with the rig choosen.

Yes, that is very true.


A Bermuda Sloop, and basicly all sloops should have a M/F ~1 since
everything else fast incease other backsides.

That depends on your goals. A lot of very practical sloops seem to to
have a luff/foot of about 1.5 ~ 1.8 sometimes more. Of course there are
those with shorter rigs & longer booms, many of them sail well too. It's
a question of getting the right sail area, the right foils, and putting
them in the right place on the hull.




Making a small jib you could just as well use a Bermuda Cat (no jib).

Not necessarily. A small jib is helpful in several ways, including going
to windward, handling the boat in a chop, and helping the boat maneuver.


Explain how a very small jib will improve on a decreased Cat. (same total
area and both correctly balanced to CLA)

Why insist on keeping area constant?

No, that is not for The design, but for the rational thinking and
understanding of how things relate to each other.

You can't describe something to another person, and in your head, without
telling changeing other stuff... then it becomes totally irrational (not as
a fact, but for all others to understand).

The only real acceptable reason to step away from M/F=1 is if a cuddy
doesn't allow one sail to stand low or if you must avoid some stayes and
must reduce one sail of structural reasons. ...which naturally should hav
ebeen taken care of earlier in the design process (in a perfect world).


My point is that jib can help very much under some conditions (for
example, helping the flow across the lee side of the lower portion of a
low aspect mainsail), it's handy for maneuvering, it looks nice, and it
helps stave off boredom. It does add to the cost though.

Probably a good point.



FWIW I don't like self tacking jibs except on racing boats where you're
likely to be very busy with other more important tasks. Self tacking
adds rigging & clutter that a cruiser would probably be better off
without. Plus, no self tacking sheeting arrangement sheets the sail
effectively for a wide range of courses, for example you can have it set
up for going cloe-hauled (the most common arrangement) and it's all but
useless on a reach... when a racing boat would be setting a spinnaker
anyway, but you probably wouldn't be.


"going cloe-hauled (the most common arrangement)" ? sorry, don't
understand.

If you set up the self-tacking jib so that it can be trimmed to be most
effective when close hauled, it will not be anywhere near as effective
on other points of sail. This doesn't seem to bother some people.


A self tacking boom arrangement attract me most. Someone called it "old
Petrus boom".

Never heard of that. Anyway, I hope this helps.

Some say that teachers learn as long as they have pupils, so I hope you
learn too.... :o)


Morgan O.

On 14 Oct 2004 21:32:17 GMT, Stephen Baker wrote:

Morgan O says:

I get a little tiered of those who call themselves designers and only whant
people to buy books or get stuffed...

If you'd like to pay the $50 per hour consultation fee that I usually charge
(and get), then I would be happy to entertain all your questions at great
length ;-)
However, if you are looking for free-ish info, then the book is as good as it
gets.

You know... usenet isn't really a market.

It's as simple as that!


I'm greatful for those who like a debate... but if anyone tries to embaress
me or others for not being educated enough before debating... he will get a
straight boot up his ass!

This is not an area ONLY for the already enlightened. It's as simple as
that!


Morgan O.

Morgan says:

You know... usenet isn't really a market.

Nor is it a place where advice must be freely given to all that ask. I am not
here to sell anything. Nor am I here to give free advice to those who complain
when I suggest that a book might be the best answer.

This is not an area ONLY for the already enlightened. It's as simple as
that!

That is very true - but it is an area where a great many people are giving away
the information that they usually get paid to know, for free.
Why do I offer free advice on Usenet, when this is my business and what puts
food on my table? Well, that's a damn'd good question right now.

Steve "think about it...."

Morgan Ohlson wrote
SNIP:

This is not an area ONLY for the already enlightened.

SNIP
Morgan O.

However, those who are resolutely UNenlightened and don't recognize good advice
when it's offered won't get good answers after a while.

Morgan Ohlson wrote in message ...

I get a little tiered of those who call themselves designers and only whant
people to buy books or get stuffed...
Morgan O.


Holy crap! You come here with basically nothing asking for free help.
You get two professional working designers helping you on your threads
and you respond with this? If I were Evan and Steve, I would tell you
to get stuffed... And to make my personal observation watching your
threads for the last few weeks, I would note that even folks like Monk
and Gardner say that is will be a matter of luck if you can get a
first try at balancing a sail on a new boat right the first time, even
with all the calculations. And screw me, but I hope you end up with a
hard lee helm. Spoiled children, geeeeze...

Yeah, the Backyard Renegade...

On 15 Oct 2004 10:00:40 GMT, Stephen Baker wrote:

Morgan says:

You know... usenet isn't really a market.

Nor is it a place where advice must be freely given to all that ask.

Ahaa, so we started flaming now!?

So utterly low.


Morgan O.

Morgan Ohlson wrote:
*** Jib size or Main/Foretriangle Ratio ***

If very theoretically 1 (equally large) must be the best. It lowers
(vertically) the CE to minimum and the shortest possible mast is needed.

1. What says that the main should be bigger?

2.Some boats have M/F-ratios of 4. That seems really stupid.

3. Is a self tacking jib a matter of importance when regarding the
M/F-ratio?

Ratio itself is just a number which in itself is not important.

Self tacking or not doesn't matter, really, except that self tacking
jibs must be smaller than the space in which they are flown, as the
jib club foot must pass between the headstay gooseneck and the mast.
It may also be required to pass in front of the foreward shrouds,
if other considerations permit using the club somewhat off the wind.

Interference with the pulpit bases while winged out is a
consideration. I prefer the longest possible club, so as to enable
flattening the jib in a constant way wrt the actual sheeting angle,
critical to good windward speed. All that depends on the geometery
and the system employed. The main advantage I find with a self
tending jib is really sheeting angle. Inboard sheeting angles permit
much better pointing, superior performance over a big baggy outboard
genny when there is enough apparrent wind. Off the wind I lower the
club and use regular outboard sheets, which are always attached even
when both are lazy, when using the "automatic" rig.

The actual ratio between sails isn't the key, here. It is a question
of balance overall and the relationship between sails in total verus
keel and rudder. A small jib may well improve weather helm over
going without.

Improve means reduce or increase, depending on your circumstances.

Terry K

On 15 Oct 2004 06:24:48 -0700, (Backyard
Renegade) wrote:

Morgan Ohlson wrote in message ...

I get a little tired of those who call themselves designers and only want
people to buy books or []...
Morgan O.


Holy crap! You come here with basically nothing asking for free help.
You get two professional working designers helping you on your threads
and you respond with this? If I were Evan and Steve, I would tell you
to []...
.....
Yeah, the Backyard Renegade...

What he (BR) said....

Brian W

Brian Whatcott ) writes:
On 15 Oct 2004 06:24:48 -0700, (Backyard
Renegade) wrote:

Morgan Ohlson wrote in message ...

I get a little tired of those who call themselves designers and only want
people to buy books or []...
Morgan O.


Holy crap! You come here with basically nothing asking for free help.
You get two professional working designers helping you on your threads
and you respond with this? If I were Evan and Steve, I would tell you
to []...
....
Yeah, the Backyard Renegade...

What he (BR) said....

I disagree. The guy's an engineer and bound to be picky. You have to make
allowances for engineers.

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An engineer who doesn't know that the centroid of a triangle is always at 1/3 of the triangle's altitude (that's
math-speak for the 'How high is the center of effort?' question.) needs a refresher course.

"William R. Watt" wrote:

Brian Whatcott ) writes:
On 15 Oct 2004 06:24:48 -0700, (Backyard
Renegade) wrote:

Morgan Ohlson wrote in message ...

I get a little tired of those who call themselves designers and only want
people to buy books or []...
Morgan O.


Holy crap! You come here with basically nothing asking for free help.
You get two professional working designers helping you on your threads
and you respond with this? If I were Evan and Steve, I would tell you
to []...
....
Yeah, the Backyard Renegade...

What he (BR) said....

I disagree. The guy's an engineer and bound to be picky. You have to make
allowances for engineers.

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Morgan says:

Ahaa, so we started flaming now!?

I see no flames - just my opinion.

So utterly low.

STANDARD USENET BONEHEAD REPLY FORM (Version 9.5) ---- Written by: John Henry
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Or something like that ;-)

On Fri, 15 Oct 2004 21:21:21 GMT, Jim Conlin wrote:

An engineer who doesn't know that the centroid of a triangle is always at 1/3 of the triangle's altitude (that's
math-speak for the 'How high is the center of effort?' question.) needs a refresher course.

"William R. Watt" wrote:

Brian Whatcott ) writes:
On 15 Oct 2004 06:24:48 -0700, (Backyard
Renegade) wrote:

Morgan Ohlson wrote in message ...

I get a little tired of those who call themselves designers and only want
people to buy books or []...
Morgan O.


Holy crap! You come here with basically nothing asking for free help.
You get two professional working designers helping you on your threads
and you respond with this? If I were Evan and Steve, I would tell you
to []...
....
Yeah, the Backyard Renegade...

What he (BR) said....

I disagree. The guy's an engineer and bound to be picky. You have to make
allowances for engineers.

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Are you actually saying that you step out in the debate whith that kind of
fascistoid oppinions, aggressiv style and beliving anyone are taking you for
serious?

To the tech Q.... Two differnently sized (hight) triangles will have the CE
at different hight. But, if, say if I had expressed my self ambigous
couldn't you accept taht, in that case... or is that beyond your abilities?

So please, if you have to put really stupid words into other persons mouths
to improve your own position... do that somewhere else.


Morgan O.

On Fri, 15 Oct 2004 11:04:10 -0300, Terry Spragg wrote:

Morgan Ohlson wrote:
*** Jib size or Main/Foretriangle Ratio ***

If very theoretically 1 (equally large) must be the best. It lowers
(vertically) the CE to minimum and the shortest possible mast is needed.

1. What says that the main should be bigger?

2.Some boats have M/F-ratios of 4. That seems really stupid.

3. Is a self tacking jib a matter of importance when regarding the
M/F-ratio?

Ratio itself is just a number which in itself is not important.

True... numbers itself is for numbrologists ;o)



Self tacking or not doesn't matter, really, except that self tacking
jibs must be smaller than the space in which they are flown, as the
jib club foot must pass between the headstay gooseneck and the mast.
It may also be required to pass in front of the foreward shrouds,
if other considerations permit using the club somewhat off the wind.

Good, I'm going for unstayed so shrouds isn't much of a problem :o)


Interference with the pulpit bases while winged out is a
consideration. I prefer the longest possible club, so as to enable
flattening the jib in a constant way wrt the actual sheeting angle,
critical to good windward speed.

Club... is that the boom? sorry, it's the eng. vocabulary...

But I understand that you focus on the possibility to haul in the jib
properly going towards weather.

That will make the sheet angle towards the forstay crucial, wouldn't it?


All that depends on the geometery
and the system employed. The main advantage I find with a self
tending jib is really sheeting angle.

ahhaa.


Inboard sheeting angles permit
much better pointing, superior performance over a big baggy outboard
genny when there is enough apparrent wind. Off the wind I lower the
club and use regular outboard sheets, which are always attached even
when both are lazy, when using the "automatic" rig.

The actual ratio between sails isn't the key, here. It is a question
of balance overall and the relationship between sails in total verus
keel and rudder. A small jib may well improve weather helm over
going without.

If I go for a Cat rig I will get a very high mast, right! ..but if I have
I big jib (same total area) I can shorten the mast. Why wouldn't that be an
issue?

Morgan O.