"Joe" wrote
good suggestion for a planing hull, bad bad ideal for a non-planning
hull, drag would have you pitch poling right away.


I don't think so, Joe. What's planing and what's non-planing? It's only so on
a horizontal surface. On tilted water it has no meaning. A sailboat hull can't plane
on flat water. There's not enough power in the engine or sails to make it go fast
enough. But it can when it's going downhill when the hill's steep enough. Gravity gives
you enough power. Your boat would be able to break out of the wave train it makes.
The reason is because the front of the bow wave is almost horizontal on a steep hill
of water instead of being too steep to get up like it is on horizontal water.
What do you think?

Cheers,
Ellen

Ellen MacArthur wrote:
"Joe" wrote
good suggestion for a planing hull, bad bad ideal for a non-planning
hull, drag would have you pitch poling right away.


I don't think so, Joe. What's planing and what's non-planing?


Planing allows the boat to go faster by using its speed and hull shape
to lift the front part of the hull out of the water. The boat travels
on top of the water, greatly reducing the hydrodynamic drag on the
vessel. The increase in aerodynamic drag is small by comparison, and
can be compensated for by the increased power from the sails due to the
faster speed of the craft, and by the crew trimming the sails.

The term 'planing' refers to a craft which is predominantly supported
by hydrodynamic lift, rather than hydrostatic lift (bouyancy). The
extent to which a boat is said to be planing is usually derived from
the dimensionless 'Froude Number'.

The earliest documented planing sailboat was a proa built in 1898 by
Commodore Ralph Munroe; it was capable of speeds of more than twice the
hull speed.

Planing a sailing dinghy was first popularised by Uffa Fox in Britain.
In 1928 Uffa Fox introduced planing to the racing world in his
International 14 dinghy, the Avenger. It had been designed with a hull
shape which permitted planing. He gained 52 first places, two seconds
and three third places out of 57 race starts that year.

Obviously this performance had an impact: other designers took on his
ideas and developed them. Over the years, most dinghies have acquired
some ability to plane, and there are now many high-performance dinghies
(usually called skiffs, see these examples, or these in [1]), which
will plane even in light winds, at all points of sail.


How planing works
Normally a non-planing, displacement, hull is restricted in its maximum
speed by a formula related to its overall length , where HSPD (in
knots) is maximum hull speed, and LWL is the hull length in feet at
waterline. This speed is maximised when the boat sits between the bow
and stern waves, with no intervening self-caused waves along its
length.

At low speeds, a hydroplaning hull acts as a displacement hull. But,
when the speed increases the hull begins acting as a planing hull.
However, when the boat begins to plane the formula becomes irrelevant
since the boat is climbing its own bow-wave. The bow rises slightly as
it starts by mounting its own bow wave. When it reaches the speed where
it overtakes the bow wave, the bow resumes its normal attitude. The
boat can often be seen to leave its stern-wave some distance behind it.
The hull is now planing.

Beginning to plane is the aquatic, and less dramatic, equivalent of an
aeroplane breaking the sound barrier. The aeroplane at Mach 1 begins to
pierce and go beyond its own 'bow wave', i.e. the compressed layers of
air on its front surfaces and ahead of it.

A hydroplaning hull travels faster and more efficiently than a
displacement hull of comparable size due to two factors:

less area of the hull is in contact with the water. This reduces the
friction on the hull caused by water. the hull is displacing less water
from its path. Water is relatively heavy and a displacing hull must
displace its own weight of water.

The characteristics of a planing hull are that it is narrow at the
prow, with a broader beam towards the rear. The shape of the underneath
of the rear of a larger, planing, powerboat is often V shaped. To
plane, the power to weight ratio must be high; sailing boats need a
good sail area and powerboats need a highly powered engine.

Note that under some high wind conditions, very light craft (such as
windsurfers and kitesurfers) can actually be pulled up onto the surface
of the water, or into the air, by the upward lift of the sail alone.
Although this certainly reduces water resistance, it is probably better
described as flying, rather than hydroplaning. It is also not a
sustainable state, as sailing (or kite flying) involves the extraction
of energy from the shear force between the wind and the water. If the
entire hull leaves the water, the craft will quickly come to rest
relative to the wind, and lose its lifting/driving force.


How to plane in a sailing boat
Planing can happen in a suitably designed boat in moderate to strong
winds if the crew do some or all of the following:

Sail on a reach or broad reach to begin
Slacken the jib
Raise the centreboard
Increase the speed
Keep the hull level, trapeze if necessary
Observe the wake until it is smooth and fast
Move the crew weight increasingly towards the rear to begin and to
sustain planing
Sheet in as speed increases, and apparent wind correspondingly moves
forward
Keep the boat flat and level
Bear away to maintain speed as necessary
Flick or pump the sails (although there are restrictions on doing this
in a race)
While planing, keep control of the waves and steer through them,
avoiding to increase speed to collide with the wave in front. Also, in
dinghies, keep good control of the sail power. A small change in wind
direction can easily cause a capsize, watch also out for gybes. Boat
control becomes easier as planing begins, but fast reactions are often
needed to get there, to keep the speed up and to keep the boat level.
Crew balance and trim are vital, as are sail trimming and minimal
centreboard



It's only so on
a horizontal surface. On tilted water it has no meaning. A sailboat hull can't plane
on flat water. There's not enough power in the engine or sails to make it go fast
enough. But it can when it's going downhill when the hill's steep enough. Gravity gives
you enough power. Your boat would be able to break out of the wave train it makes.
The reason is because the front of the bow wave is almost horizontal on a steep hill
of water instead of being too steep to get up like it is on horizontal water.
What do you think?

I think before I got 65,000 lbs on plane with a displacement hull I
would be in a vertical position racing to stuff the bow deep into the
wave leaving to a classic pitchpole like this:

http://www.bymnews.com/photos/albums...ormal_Git1.jpg

Joe



Cheers,
Ellen

"Joe" wrote

http://www.bymnews.com/photos/albums...ormal_Git1.jpg

Those trimarans certainly can go fast enough to pitchpole. And you're right it's usually
because they go so fast they stuff the bow into the back of a wave.
Dame Ellen can have them.
But, I don't think a monohull with ballast on the bottom would suffer such a fate. They
just don't go so fast even down the face of a wave. They would stay on the wave and never
get a chance to hit the next wave in the backside. Also, if your going across the wave at 45
degrees like a surfer you stay in place on the face of the wave even if your going very fast.
You'd have to have a boat with good rudder control. But, I think it would be a safer thing
to do than trying to go straight up a huge wave. You'd just have to hang in there till the wave
wore itself out. A wave that big just can't be that wide for more than a mile or two. What
would that be if your surfing along at ten to fifteen knots? About fifteen minutes? Doable.

Cheers,
Ellen

Ellen MacArthur wrote:
Also, if your going across the wave at 45
degrees like a surfer you stay in place on the face of the wave even if your going very fast.

If you thinking of kicking out in front of a tube then you need to be
in a area a wave is breaking.

A rouge can be a wall 100+ ft tall, you try to run down the face of a
wall at 45 you going to tube roll and be in a waching machine for quite
a while. Punching thru and over is your only hope.

http://lifesjestbook.typepad.com/men..._storm_001.jpg



You'd have to have a boat with good rudder control. But, I think it would be a safer thing
to do than trying to go straight up a huge wave. You'd just have to hang in there till the wave
wore itself out. A wave that big just can't be that wide for more than a mile or two. What
would that be if your surfing along at ten to fifteen knots? About fifteen minutes? Doable.

Good luck.

Joe


Cheers,
Ellen

"Joe" wrote
http://lifesjestbook.typepad.com/men..._storm_001.jpg

That picture shows how far the Andrea Gail has to fall and tumble. You just
can't punch through a wave with a little boat. (unless your driving a submarine)
You can't make a whole boat sink under a wave with power. It will stay on the
surface. If it's long, really long, longer than the wave length then maybe the bow
will go under for a few seconds as the wave sweeps along the hull but the whole
boat isn't punching under the surface.
Back to the small boat.... The minute water from the wave gets inside the diesel air
intake there goes the engine. Then the boat's dead in the water. Under water if
the crest falls on it. So what happens you get rolled and slammed off the top of
the wave all the way to the bottom.
http://www.indiana.edu/%7Eg131/waves4.gif
If the Andrea Gail would've tried to surf the wave to get out of the way
of the breaking crest they would've had a chance at least. The way they tried
to do it was a death sentence. I don't think real ships captains would try to power
straight up a wave like that. Where's Otn when we need him? I bet he wouldn't power
his pilot boat with it's two powerful diesels straight up a rogue wave face.
That reminds me something I was gonna ask him..... Who drives the pilot boat out
to the ship and who drives it back? Do pilots ever drive the pilot boat or do they just
go along for the ride and pilot the ships they're put on.

Cheers,
Ellen

Ellen MacArthur wrote:
.. I don't think real ships captains would try to power
straight up a wave like that.

I know they would, you gave good reason, most ships have a longer wave
length and will punch thru.

I think whenever the wave height is longer than your waterline and has
a shorter length then you in deep trouble and are at the mercy of the
sea no matter what you do.


Where's Otn when we need him? I bet he wouldn't power
his pilot boat with it's two powerful diesels straight up a rogue wave face.
That reminds me something I was gonna ask him..... Who drives the pilot boat out
to the ship and who drives it back? Do pilots ever drive the pilot boat or do they just
go along for the ride and pilot the ships they're put on.

Both...mostly pilots in training.

Joe

Cheers,
Ellen

Joe,

Neal has made that statement about waves before and as usual he's full
of S--t. His whole scenario is riddled with wrong stupid assumption. The
first and dumbest is comparing a displacement hull with a Surf board.
Can anyone that has ever been in a Sea way ever tried to control a
displacement hull in near free fall on the face of a wave with a rudder?
A wave that large creates a sucking action into the wave. Something he
is ignoring or is completely unaware of. He assumes his hull would be on
a level plane like a surf board when in reality it would be heeled
badly. Badly enough that you'd could only hang on. You wouldn't be able
to move.

When he make statements like that, it is because he is speaking through
a "Sock-puppet" but I've read his mentality on waves before and it is
DAMN STUPID AND DANGEROUS!! His "Cut the Mustard" carries a broken
Boom, Which according to him, happened in a wave entering a channel.

DON"T LISTEN TO HIM! I don't think he has ever Battened Down and had
the let the Vessel take care of him and itself. He just doesn't know.


http://community.webtv.net/tassail/ILLDRINKTOTHAT






http://community.webtv.net/tassail/GOODNITE

"Thom Stewart" wrote
Neal has made that statement about waves before and as usual he's full
of S--t. His whole scenario is riddled with wrong stupid assumption. The
first and dumbest is comparing a displacement hull with a Surf board.
Can anyone that has ever been in a Sea way ever tried to control a
displacement hull in near free fall on the face of a wave with a rudder?
A wave that large creates a sucking action into the wave. Something he
is ignoring or is completely unaware of. He assumes his hull would be on
a level plane like a surf board when in reality it would be heeled
badly. Badly enough that you'd could only hang on. You wouldn't be able
to move.

I don't know about what Capt. Neal said but if he said to try surfing down and across the
wave then he's got it right IMO. It makes perfect sense to me. I'm glad we think alike.
Your wrong about a wave making a sucking action. Look at the link I gave Joe. It has a little
circle in the wave. It shows which way the water goes. The arrows show the opposite of a sucking
action. Being a woman I know all about sucking action. :-). Just kidding, don't get all excited, Tom.
You said the hull would be heeled badly. I don't think so. Rogue waves travel fast. Very fast.
Just imagine the apparent wind. If the wave was going fifty miles an hour and the wind was calm
you'd have a fifty miles an hour wind at the top of the wave. That's what blows the spray back.
But at the bottom of the wave the wind would be less but still strong enough to keep the boat level.
It would be blowing against the tilt of the wave so things would balance. That's why I said to sheet
the sails in tight.

When he make statements like that, it is because he is speaking through
a "Sock-puppet" but I've read his mentality on waves before and it is
DAMN STUPID AND DANGEROUS!! His "Cut the Mustard" carries a broken
Boom, Which according to him, happened in a wave entering a channel.

Whatever, but it sound like he's got it right to me..... Tom, I was reading a good book last night. This is
what it says about big waves and sailing in them. It agrees with what I'm saying. That's mostly why I said it.

"4) If truly enormous seas threaten to engulf the vessel you can try oil...... You can cut away some or all the warps
and begin to steer by hand, bearing off a little when the yacht rises on a big sea. This will require careful steering,
and crew exhaustion will become a factor. Let's hope you will never get to this point."

This is the fourth of four steps to sailing in heavy weather. The first three are heave to, lie ahull, run with the
storm with warps trailing astern. Know who wrote it? Hal Roth in his book, After 50,000 Miles.
So your telling people to not listen to Hal Roth, Duh, I think he's got more experience even than Capt. Neal does.
And certainly much more than you do......
Joe's talking about one big rogue wave. Exhaustion's no problem, careful steering's the most important thing.
Just like I said.

Cheers,
Ellen

Thom Stewart wrote:
Joe,

Neal has made that statement about waves before and as usual he's full
of S--t. His whole scenario is riddled with wrong stupid assumption. The
first and dumbest is comparing a displacement hull with a Surf board.
Can anyone that has ever been in a Sea way ever tried to control a
displacement hull in near free fall on the face of a wave with a rudder?
A wave that large creates a sucking action into the wave. Something he
is ignoring or is completely unaware of. He assumes his hull would be on
a level plane like a surf board when in reality it would be heeled
badly. Badly enough that you'd could only hang on. You wouldn't be able
to move.

No doubt Ol Thom, a displacement hull has no chance of steering on
plane.
Can you just imagine "Ellen" standing in the cockpit of her Tangerine
like a surfer kicking out of a 100 footer...hehehehe.

Even the planing boats getting hit from astern have little chance as
discovered by Hatfield from Canada.

The 7880 nm Leg 4 of Around Alone from Tauranga NZ to Salvador (Brazil)
round the notoriously rough Cape Horn has claimed two booms, two masts,
damaged two keels caused a pitch-poling (end-over-end capsize) and
forced Kiwi Graham Dalton on his Open 60 Hexagon to retire from the
race entirely. The ports of Mar del Plata and Ushuaia in southern
Argentina and Port Stanley in the Falkland Islands have been extremely
busy receiving the yachts, effecting emergency repairs before sending
the competitors on their way.

Winds of around 70 knots and 40 foot high waves have been recorded and
Canadian skipper Derek Hatfield (before dismasting his Open 40 Spirit
of Canada) joined a long line of mariners who have been fooled by Deigo
Ramirez, a small rocky archipelago 30 miles west of Cape Horn that have
scared the fillings out of many sailors who have come up on the group
in the middle of the night and suddenly seen the lights on the wrong
side of the boat.

Hatfield's pitch-poling story is pretty amazing: It was sometime
mid-afternoon when the wave that had his name on it came up from
behind. "I was so exhausted that I could hardly think, but when I heard
the wave I knew that I was in trouble. It was not as big as some of the
others, but was breaking and it made a huge roar as it approached the
boat. In seconds we were falling down the face of it until the bow dug
in and then we pitch-poled. The boat went straight up and then fell
over sideways. I was at the back of the boat and got flung forward, and
the next thing I knew I was in the water under the boat."

Derek continued his story. "I heard the water gurgling and knew that I
was under the boat, then all of a sudden I heard loud explosions that
reverberated through the water and I knew in a instant that the mast
was breaking. It was unreal. Gurgling water and huge bangs. Suddenly
without the mast the boat came back upright and I was dragged back on
deck." Derek is amazed and gratified by the outpouring of support he
has been receiving including Emma Richards sponsor Andrew Pindar offer
to fund a spare mast is starting to feel a bit confident that he might
just be able to get back into the race. Read further updates on this
remarkable story at: www.aroundalone.com



When he make statements like that, it is because he is speaking through
a "Sock-puppet" but I've read his mentality on waves before and it is
DAMN STUPID AND DANGEROUS!! His "Cut the Mustard" carries a broken
Boom, Which according to him, happened in a wave entering a channel.

DON"T LISTEN TO HIM! I don't think he has ever Battened Down and had
the let the Vessel take care of him and itself. He just doesn't know.


http://community.webtv.net/tassail/ILLDRINKTOTHAT






http://community.webtv.net/tassail/GOODNITE

"Ellen MacArthur" wrote in
message
reenews.ne
t...

"Joe" wrote


http://www.bymnews.com/photos/albums...10006/normal_G
it1.jpg

Those trimarans certainly can go fast enough to
pitchpole. And you're right it's usually
because they go so fast they stuff the bow into the back
of a wave.
Dame Ellen can have them.
But, I don't think a monohull with ballast on the
bottom would suffer such a fate. They
just don't go so fast even down the face of a wave. They
would stay on the wave and never
get a chance to hit the next wave in the backside. Also,
if your going across the wave at 45
degrees like a surfer you stay in place on the face of the
wave even if your going very fast.
You'd have to have a boat with good rudder control.
But, I think it would be a safer thing
to do than trying to go straight up a huge wave. You'd
just have to hang in there till the wave
wore itself out. A wave that big just can't be that wide
for more than a mile or two. What
would that be if your surfing along at ten to fifteen
knots? About fifteen minutes? Doable.


Doable on a Mac 26 XM maybe.

Scotty