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Old 30-12-2011, 19:27   #91
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Where does the 50-knot speed of storms come from? I have always been told it is 12 knots!

cheers,
Nick.
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Old 31-12-2011, 06:56   #92
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Originally Posted by s/v Jedi
Where does the 50-knot speed of storms come from? I have always been told it is 12 knots!

cheers,
Nick.
Hmmm... Is my information wrong? Perhaps I am thinking of squall lines and T storms while you are thinking of tropical depressions? Can anyone enlighten us/me?
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Old 31-12-2011, 12:02   #93
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Originally Posted by malbert73
systems can move at 35-50 knots easily. .
Yikes! Must be one of those new Category 48 hurricanes. Maybe somebody needs to go back to weather school?

Let me recommend a book--Modern Marine Weather by David Burch. Section 4.8 is about Storm Avoidance Maneuvering. You will learn that with good forecasting it's entirely possible to avoid tropic storms that are traveling twice your speed. The most I've ever heard of a tropical storm moving is 19 knots, but they're more commonly going to move somewhere around 11 knots.

So do a little math here. Storm Foxtrot is moving at 12 knots on a course perpendicular to two sailboats, and is 200 nm out. Boat #1 cruises at an average speed of four knots. Boat #2 cruises at an average speed of eight knots. How much further from the storm's path can Boat #2 be by the storms CPA, assuming both boats know the ideal alpha angle to sail?

Hardly a month goes by here on CF where some fellow in a 4-kt-4ever boat proclaims that faster boats can't outrun storms. Well, if the storms are moving 50 knots, that might be true. But in the real world, storms just don't move that fast.
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Old 31-12-2011, 13:04   #94
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Re: Heaving To With a Fin Keel...

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Originally Posted by jobi View Post
Many sugestions have been made...however thats is not what I had in mind as a DIY draugh...I have 100+ old car seat belts, I want to sew them with a palm stitcher and build a 6ft diametre net solid enough to survive any storm...pulled behind with 200ft rode?
DID IT, and it works like a charm...... Only used it once in real conditions, was still in control and running in the low teens, but it slowed us down to better than half of our speed...
I built it around a 1/2 inch piece of SS.. its about 42 inches across....
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Old 31-12-2011, 13:17   #95
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Re: Heaving To With a Fin Keel...

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Originally Posted by Bash View Post
Hardly a month goes by here on CF where some fellow in a 4-kt-4ever boat proclaims that faster boats can't outrun storms. Well, if the storms are moving 50 knots, that might be true. But in the real world, storms just don't move that fast.
In addition, its not outrunning a storm as an issue but instead, putting yourself in the storm 1/4 where the weather is of less issue..
We've found this to be true many times..
Stand with your back to the wind and look up at the clouds, they will be moving to the left or right.. Plot the storm and head for the lower following 1/4.. it will be the least affected..
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Old 31-12-2011, 13:40   #96
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Re: Heaving To With a Fin Keel...

[QUOTE=Randyonr3;849633]DID IT, and it works like a charm...... Only used it once in real conditions, was still in control and running in the low teens, but it slowed us down to better than half of our speed...
I built it around a 1/2 inch piece of SS.. its about 42 inches across....[/QUOTE

wouldent the metal sink the drogh enough to pull your stern down?

looks good
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Old 31-12-2011, 14:20   #97
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Re: Heaving To With a Fin Keel...

[QUOTE=jobi;849664]
Quote:
Originally Posted by Randyonr3 View Post
DID IT, and it works like a charm...... Only used it once in real conditions, was still in control and running in the low teens, but it slowed us down to better than half of our speed...
I built it around a 1/2 inch piece of SS.. its about 42 inches across....[/QUOTE

wouldent the metal sink the drogh enough to pull your stern down?

looks good
We didnt have any issue with it dropping and still running at a good clip.. Had about 200 feet of anchor rode out on it..
Thought about the issue of it spinning and sinking as you mentioned but a simple fender tied to the rim would solve both issues.
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Old 31-12-2011, 14:41   #98
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Originally Posted by Bash
some fin keel boats heave to better than others. My current boat, which has high freeboard and in-mast furling, can heave to under main alone if the main is furled small enough. No jib is needed because the bow's windage basically serves the function of a backed jib. I can usually control the stall angle of the boat by easing the traveler. She seems to heave to best with the traveler fully down.

People more accustomed to full-keelers claim that fin-keelers won't heave to because they point too high, and will end up tacking. That's an easy "problem" to fix with a traveler.
I obviously need to practice this more. Sure didn't work last weekend. We tried it about 6 times with a different amount of jib furled out. More practice needed
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Old 31-12-2011, 14:48   #99
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I obviously need to practice this more. Sure didn't work last weekend. We tried it about 6 times with a different amount of jib furled out. More practice needed
Did you fall off or tack through?
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Old 31-12-2011, 17:43   #100
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Tacked through
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Old 31-12-2011, 18:25   #101
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Re: Heaving To With a Fin Keel...

reef the main more, if you cant add a reef point, add some jib. play with the sails and find the happy spot.
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Old 31-12-2011, 19:16   #102
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Re: Heaving To With a Fin Keel...

Never say never. From NOAA NOAA FAQ

How fast is the hurricane moving? Most hurricanes may move along at 10-20 mph, but in extreme cases, they could be moving as fast at 40 mph (pretty rare),

One of my weather books said 50 but 40 is close. It said as long as the storm is traveling west it will travel at the slow pace, but if it starts tracking north that's when you have to watch out for the potential to travel fast.

John

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Yikes! Must be one of those new Category 48 hurricanes. Maybe somebody needs to go back to weather school?

Let me recommend a book--Modern Marine Weather by David Burch. Section 4.8 is about Storm Avoidance Maneuvering. You will learn that with good forecasting it's entirely possible to avoid tropic storms that are traveling twice your speed. The most I've ever heard of a tropical storm moving is 19 knots, but they're more commonly going to move somewhere around 11 knots.

So do a little math here. Storm Foxtrot is moving at 12 knots on a course perpendicular to two sailboats, and is 200 nm out. Boat #1 cruises at an average speed of four knots. Boat #2 cruises at an average speed of eight knots. How much further from the storm's path can Boat #2 be by the storms CPA, assuming both boats know the ideal alpha angle to sail?

Hardly a month goes by here on CF where some fellow in a 4-kt-4ever boat proclaims that faster boats can't outrun storms. Well, if the storms are moving 50 knots, that might be true. But in the real world, storms just don't move that fast.
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Old 31-12-2011, 21:00   #103
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Re: Heaving To With a Fin Keel...

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I thought the pardeys covered heaving-to in a modern boat pretty well... am I missing something, or did nobody else read the book?

I've never had to heave-to in a storm, so I'm only repeating what I understand from the Pardey method.

Larry says; on a modern fin keeled boat you'll need to heave-to with both a jib and a main, storm sized sails obviously, and the jib would be best if on an innerforestay, or a staysail. The main should be a reefed main instead of the long-footed trisail type of shape.

Once hove-to, a parachute anchor is deployed on a bridle off the bow.

The whole parachute anchor thing they preach is specific to fin keeled boats, precisely because of all the mentioned problems in this thread.... They recommend the parachute anchor is deployed as soon the boat cannot maintain the hoave-to postion without it. This is the same recommendation for either type of boat, but it'll happen a lot sooner on a fin keeler.

Their method for heaving-to a tradional keeler is entirely different.

This is really useful information and a very clear explanation. thank you!
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Old 01-01-2012, 09:14   #104
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Re: Heaving To With a Fin Keel...

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Tacked through
I must be missing something here, you say you tacked throu with a back-winded jib?
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Old 01-01-2012, 09:23   #105
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Quote:
Originally Posted by Bash

Yikes! Must be one of those new Category 48 hurricanes. Maybe somebody needs to go back to weather school?

Let me recommend a book--Modern Marine Weather by David Burch. Section 4.8 is about Storm Avoidance Maneuvering. You will learn that with good forecasting it's entirely possible to avoid tropic storms that are traveling twice your speed. The most I've ever heard of a tropical storm moving is 19 knots, but they're more commonly going to move somewhere around 11 knots.

So do a little math here. Storm Foxtrot is moving at 12 knots on a course perpendicular to two sailboats, and is 200 nm out. Boat #1 cruises at an average speed of four knots. Boat #2 cruises at an average speed of eight knots. How much further from the storm's path can Boat #2 be by the storms CPA, assuming both boats know the ideal alpha angle to sail?

Hardly a month goes by here on CF where some fellow in a 4-kt-4ever boat proclaims that faster boats can't outrun storms. Well, if the storms are moving 50 knots, that might be true. But in the real world, storms just don't move that fast.

Ha ha, must be a bummer to be stuck in a boat with a 9 foot waterline that can only manage 4 knots. I'd never cruise a boat that didn't easily sail 6 knots in moderate breeze.

Yes, bigger boats are faster on average, but not as much in real world conditions as the "big boatistas" like to proclaim. If your 45-50 footer has a waterline of 42 feet, your calculated hull speed is 8.7 knots. my 33 footer with its 25 foot waterline has calculated hull speed of 6.7 knots. I doubt either of us ever average our hull speed easily, and I don't doubt that speed helps you get out of the way, but it's not like well designed smaller boats are that far off the pace....

If you're talking about a tropical depression moving at a slow pace, it's going to take perfect timing for your speed difference to allow you to completely avoid a storm but obviously if you can afford a bigger boat then you'll have a better chance.
A fast moving squall line or localized set of cells, which is much more real world to encounter DOES move much faster (please read up on those-
And in those cases speed doesn't make a difference for avoidance.
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