I am a newbie on a Laser Pico. Can someone explain to me what the jib sail
does and how it works?

"James L" wrote...
I am a newbie on a Laser Pico. Can someone explain to me what the jib
sail
does and how it works?

It balances the rig to relieve pressure on the tiller, adds sail area, and
provides an aerodynamic "slot" in front of the main to accelerate the
airflow and increase efficiency of the main.

Adjust the jib similar to the main -- the luff should be pointing into the
relative wind except when running before the wind.

Thank you.

How does it relieve the pressure on the tiller? I do notice a strong force
on the tiller when there is some wind. I don't remember this on the Topper
that I used to sail earlier.

"John R Weiss" wrote in message
news:KebNc.190772$XM6.183421@attbi_s53...
"James L" wrote...
I am a newbie on a Laser Pico. Can someone explain to me what the jib
sail
does and how it works?

It balances the rig to relieve pressure on the tiller, adds sail area, and
provides an aerodynamic "slot" in front of the main to accelerate the
airflow and increase efficiency of the main.

Adjust the jib similar to the main -- the luff should be pointing into the
relative wind except when running before the wind.

"James L" wrote...

How does it relieve the pressure on the tiller? I do notice a strong force
on the tiller when there is some wind. I don't remember this on the Topper
that I used to sail earlier.

A properly rigged boat will be "balanced" when the sails are trimmed on most
points of sail. In this context, "balanced" means you need little or no tiller
pressure to maintain a straight course. Most boats are rigged with a little
"weather helm" -- the tendency to turn into the wind -- when the tiller is
released. This gives a bit of safety factor, so the boat won't run downwind out
of control if you temporarily lose control of the tiller.

With a jib and main, you can fine-tune the rig balance. Tightening the jib a
bit more (relative to the main) will create more downwind force on the bow,
causing a "lee helm" -- turning away from the wind -- tendency. Easing the jib
relative to the main will reduce the jib's effectiveness slightly, giving more
weather helm.

Finally, when running dead downwind, the jib can be set on the opposite side of
the boat from the main, called "wing and wing." The boat's tendency to turn
into the wind will be much reduced, and the power of the jib will be much more
effective.

In article , "James L"
wrote:

Thank you.

How does it relieve the pressure on the tiller? I do notice a strong force
on the tiller when there is some wind. I don't remember this on the Topper
that I used to sail earlier.

Very simply, the jib is set forward of the centre of lateral resistance
(the point about which all the lateral resistance of the hull and
underwater appendages combine to act) and the main is set aft of that
centre. If there's a large force on the tiller caused by the boat
wanting to turn up into the wind, then ease the main a little and trim
the jib a little tighter. If the force is caused by the boat wanting to
turn away from the wind, reverse it: main in, jib eased.



"John R Weiss" wrote in message
news:KebNc.190772$XM6.183421@attbi_s53...
"James L" wrote...
I am a newbie on a Laser Pico. Can someone explain to me what the jib
sail
does and how it works?

It balances the rig to relieve pressure on the tiller, adds sail area, and
provides an aerodynamic "slot" in front of the main to accelerate the
airflow and increase efficiency of the main.

Adjust the jib similar to the main -- the luff should be pointing into the
relative wind except when running before the wind.



--
Alan Baker
Vancouver, British Columbia
"If you raise the ceiling 4 feet, move the fireplace from that wall
to that wall, you'll still only get the full stereophonic effect
if you sit in the bottom of that cupboard."

Very correct.

Also there is a less visible effect due to the heel angle. If you view the
boat from the top and project the "centers of forces" (approximate) on the
horizontal plane, you see the arm of the moment that turns the nose up
increases with heel angle. This is the reason why heeling has lots to do
with tiller feedback and load.

Put in a practical way, you'd get a lot of load when the boat is too heeled.
Don't let her heel more than what you feel good. If she did, let her point
up slightly and release some load. If she permanently does, you're not
beating high enough.


"Alan Baker" ha scritto nel messaggio
...
In article , "James L"
wrote:

Thank you.

How does it relieve the pressure on the tiller? I do notice a strong
force
on the tiller when there is some wind. I don't remember this on the
Topper
that I used to sail earlier.

Very simply, the jib is set forward of the centre of lateral resistance
(the point about which all the lateral resistance of the hull and
underwater appendages combine to act) and the main is set aft of that
centre. If there's a large force on the tiller caused by the boat
wanting to turn up into the wind, then ease the main a little and trim
the jib a little tighter. If the force is caused by the boat wanting to
turn away from the wind, reverse it: main in, jib eased.



"John R Weiss" wrote in message
news:KebNc.190772$XM6.183421@attbi_s53...
"James L" wrote...
I am a newbie on a Laser Pico. Can someone explain to me what the
jib
sail
does and how it works?

It balances the rig to relieve pressure on the tiller, adds sail area,
and
provides an aerodynamic "slot" in front of the main to accelerate the
airflow and increase efficiency of the main.

Adjust the jib similar to the main -- the luff should be pointing into
the
relative wind except when running before the wind.



--
Alan Baker
Vancouver, British Columbia
"If you raise the ceiling 4 feet, move the fireplace from that wall
to that wall, you'll still only get the full stereophonic effect
if you sit in the bottom of that cupboard."

The main reason for a jib to exist is that its profile combines with that of
the mainsail when going upwind in a way that increase considerably the
overall lift. The reason is very aerodynamical and not very easy to
visualise, it has to do with the combination of the fluid flow
circuitations.

On the other courses it's more square metres of sail there to push more
without adding extra heeling on the boat, since they are at low height above
the center of buoyancy.

At the beginning of your career you'll find very easy to steer the boat
upwind just on how the little red and green lines fly near the luff.


"James L" ha scritto nel messaggio
...
I am a newbie on a Laser Pico. Can someone explain to me what the jib
sail
does and how it works?

Thank you, but it raises more questions.

Won't the jib interfere with the main sail as it sits right in front of the
mail sail albeit of smaller size?

When running, doesn't the mail sail block the jib, almost completely?

What is heeling?

When you say "above the center of buoyancy" do you mean in front of the
center of buoyancy or are you talking height?

Thanks

"Gianluca" wrote in message
. ..
The main reason for a jib to exist is that its profile combines with that
of
the mainsail when going upwind in a way that increase considerably the
overall lift. The reason is very aerodynamical and not very easy to
visualise, it has to do with the combination of the fluid flow
circuitations.

On the other courses it's more square metres of sail there to push more
without adding extra heeling on the boat, since they are at low height
above
the center of buoyancy.

At the beginning of your career you'll find very easy to steer the boat
upwind just on how the little red and green lines fly near the luff.


"James L" ha scritto nel messaggio
...
I am a newbie on a Laser Pico. Can someone explain to me what the jib
sail
does and how it works?

"James L" wrote...

Won't the jib interfere with the main sail as it sits right in front of the
mail sail albeit of smaller size?

No. If properly set, the narrower "slot" between the main and jib actually
makes the main more effective, because the air is accelerated through the slot.
However, if the jib is trimmed too tightly, it will interfere with the main.


When running, doesn't the mail sail block the jib, almost completely?

Yes. However, see "wing and wing" in my previous message.


What is heeling?

The boat tipping to one side.


When you say "above the center of buoyancy" do you mean in front of the
center of buoyancy or are you talking height?

Height. The primary vertical forces are centered around the center of gravity
(depends on the distribution of weight in the boat -- down) and center of
buoyancy (depends mainly on hull shape -- up). The primary sideways horizontal
forces are centered around the center of effort (effective center of the sails)
and center of lateral resistance (underwater hull/centerboard/rudder profile,
looking from the side). Then there are the thrust from the sails and the drag
from air and water.

In article , "James L"
wrote:

Thank you, but it raises more questions.

Won't the jib interfere with the main sail as it sits right in front of the
mail sail albeit of smaller size?

It will *affect* the main sail, but the affect is positive when the
sails are trimmed correctly.


When running, doesn't the mail sail block the jib, almost completely?

Yes, if you are running dead downwind (which is slower than running at a
slight angle to the wind) and provided you don't "wing" the jib out to
the opposite side.

That's why the spinnaker was invented. g



What is heeling?

The boat tipping to the side in response to the force of the wind on the
sails.



When you say "above the center of buoyancy" do you mean in front of the
center of buoyancy or are you talking height?

Don't know where you're going here, but I'd say height.


Thanks

"Gianluca" wrote in message
. ..
The main reason for a jib to exist is that its profile combines with that
of
the mainsail when going upwind in a way that increase considerably the
overall lift. The reason is very aerodynamical and not very easy to
visualise, it has to do with the combination of the fluid flow
circuitations.

On the other courses it's more square metres of sail there to push more
without adding extra heeling on the boat, since they are at low height
above
the center of buoyancy.

At the beginning of your career you'll find very easy to steer the boat
upwind just on how the little red and green lines fly near the luff.


"James L" ha scritto nel messaggio
...
I am a newbie on a Laser Pico. Can someone explain to me what the jib
sail
does and how it works?





--
Alan Baker
Vancouver, British Columbia
"If you raise the ceiling 4 feet, move the fireplace from that wall
to that wall, you'll still only get the full stereophonic effect
if you sit in the bottom of that cupboard."