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Old 31-10-2013, 02:05   #16
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Re: roll over anyone?

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Originally Posted by robert sailor View Post
If your terribly interested in the subject matter there was a book and a Government report after the 1979 Fastnet race... which was yachtings worst disaster. They compared designs and righting moments to their benchmark boat, a Contessa 32 which had a righting moment over 155 degrees. Many of the boats were rolled during that race, most while laying a hull which is not a good strategy with breaking waves. Low ballast ratio's and wide beam also did poorly.
There's also a book Fastnet Force 10 where people from boats that were rolled were interviewed IIRC.

Once Is Enough by Smeeton describes their pitchpole and rollover in the Southern Ocean.

I'll have to open it again, but I'm pretty sure Fatal Storm by Mundle has people talking about their rollovers.

Total Loss by Coote has at least one account of a rollover, there's a series of pictures on the back cover depicting a rollover.

Santana 22 getting rolled under the Golden Gate Bridge:
April 4, 2005
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Old 31-10-2013, 03:25   #17
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Re: roll over anyone?

Apart from multihulls or monohulls that have lost their keel, I have never heard of a sailboat unable to right itself. It is illogical for a sailboat to remain inverted even if she does have her sails. The rig is not fixed in the middle, so the water forces against the sail can never cancel each other out. On top of that, the sea state will be always violent and not the same on either side. The rig will get pushed to one side, water will start moving along the sail, a pressure differential will develop, she will start to heel, and the unbalanced weight of the keel high up will do the rest. One should also remember that the boat will already have momentum when it arrives at the state of maximum inversion, making it even more unlikely she will remain inverted.


Onno
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Old 31-10-2013, 03:58   #18
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Re: roll over anyone?

Original website with all the photos of the Santana 22 seems to be gone, finally found some of the sequence here (click slide show):

H2uh0 : Cowabunga!
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Old 31-10-2013, 04:02   #19
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Re: roll over anyone?

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Originally Posted by cal40john View Post
Original website with all the photos of the Santana 22 seems to be gone, finally found some of the sequence here (click slide show):

H2uh0 : Cowabunga!
Wow, impressive. What on earth were they doing there?


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Old 31-10-2013, 05:45   #20
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Theyl l always end up rightside up,unless your hatch isnt secure, you lose a window or two, your hatch tears off, then theyll end up right side a bit deeper in the water. Lol
Hope the guy in the cockpit can hold his breath.....:-)
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Old 31-10-2013, 06:01   #21
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To the guys who have rolled a boat---- were you running under bare pole(s) or did you have a drogue or some improvised sea anchor our to hold you bow or stern to and get nailed by a rogue?

As my avatar states I am an "avid learner"

Thanks

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Old 31-10-2013, 06:39   #22
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Quote:
Originally Posted by JazzyO View Post
Apart from multihulls or monohulls that have lost their keel, I have never heard of a sailboat unable to right itself. It is illogical for a sailboat to remain inverted even if she does have her sails. The rig is not fixed in the middle, so the water forces against the sail can never cancel each other out. On top of that, the sea state will be always violent and not the same on either side. The rig will get pushed to one side, water will start moving along the sail, a pressure differential will develop, she will start to heel, and the unbalanced weight of the keel high up will do the rest. One should also remember that the boat will already have momentum when it arrives at the state of maximum inversion, making it even more unlikely she will remain inverted. Onno
There was a crazy old Brit in a mono in one of the RTW races who flipped 180 degrees a couple of thousand miles SW of Perth. IIRC the OZ Navy rescued him when he was still inverted a few days later.

He didn't lose his keel nor his cool.
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Old 31-10-2013, 09:05   #23
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Re: roll over anyone?

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Originally Posted by Jimbo485 View Post
There was a crazy old Brit in a mono in one of the RTW races who flipped 180 degrees a couple of thousand miles SW of Perth. IIRC the OZ Navy rescued him when he was still inverted a few days later.

He didn't lose his keel nor his cool.
That was on either an Open 60 or its equivalent at the time, a racing boat. These are very wide lightweight boats that are very stable upside down. After a few of these early boats remained inverted they made rules about self righting. The first version was a giant balloon on the aft deck that automatically inflated to help the righting process. Then when canting keels came out they had to prove the boat could be righted using the keel.

Qualifying test for VOR:


Discussion from the cruisers view of VOR boats:
Open 60 design trends not for voyaging boats - Ocean Navigator - January/February 2003

Article on stability of sailboats in general:
http://www.sailfeed.com/2013/05/modern-sailboat-design-quantifying-stability/

Edit: Was trying to find a picture of the balloon on the aft deck, but got off track. Do a find on this page for "capsize" on this link:
http://en.wikipedia.org/wiki/Vend%C3%A9e_Globe
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Old 31-10-2013, 10:26   #24
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Check out:

Desirable and Undesirable Characteristics of Offshore Yachts
by the Technical Committee of the Cruising Club
of America

Great insights into stability and much more
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Old 31-10-2013, 10:45   #25
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Having worked in shipbuilding, I've repaired ships that have had welded steel handrails ripped off from the force of water. So demasting due to water pressure would classify, in my book, as something not so rare and well within the bounds of reality.

To roll twice and make it past the first one would be considered lucky. The second time would likely remove the already weakened rigging.

I prefer my adrenalin to be just a wee bit diluted from that point.
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Old 31-10-2013, 11:36   #26
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Re: roll over anyone?

I'm surprised nobody is referring Adlard Coles' HEAVY WEATHER SAILING. Get an older edition
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Old 31-10-2013, 12:09   #27
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Re: roll over anyone?

Treacherous Waters : Stories of Sailors in the Clutch of the Sea: Tom Lochhaas: 9780071388849: Amazon.com: Books

This book has excerpts from people talking about their experiences. I think there was a rollover and a pitchpole.
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Old 31-10-2013, 17:42   #28
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Re: roll over anyone?

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Originally Posted by JazzyO View Post
Apart from multihulls or monohulls that have lost their keel, I have never heard of a sailboat unable to right itself. It is illogical for a sailboat to remain inverted even if she does have her sails. The rig is not fixed in the middle, so the water forces against the sail can never cancel each other out. On top of that, the sea state will be always violent and not the same on either side. The rig will get pushed to one side, water will start moving along the sail, a pressure differential will develop, she will start to heel, and the unbalanced weight of the keel high up will do the rest. One should also remember that the boat will already have momentum when it arrives at the state of maximum inversion, making it even more unlikely she will remain inverted.


Onno
what about the weight of the wet sails when they she trys to lift them back out of the water? one gallon weighs 8.55 pounds and several hundred feet of sails can hold a couple of hundred gallons with some of the weight near the top of the mast. That's likely the reason they are so commonly demisted I guess.
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Old 31-10-2013, 17:43   #29
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Re: roll over anyone?

Quote:
Originally Posted by Scott Berg View Post
Check out:

Desirable and Undesirable Characteristics of Offshore Yachts
by the Technical Committee of the Cruising Club
of America

Great insights into stability and much more
thanks
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Old 31-10-2013, 17:47   #30
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Re: roll over anyone?

All your answers are thoughtful and I wish to thank everyone. So far only one person that actually rolled over has responded that I am aware of.
It seems to me if your running bare poles a rollover would be possible with little damage but I cannot imagine a vessel under sail rolling over and not at least being demisted.
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