Can a Mono Hulled Sailboat Right Itself

[s/v 'Faith']

A well found monohull sailed appropriately in conditions that are likely to produce a rollover / knockdown will self right.

Some modern designs are nearly as stable upside down as right side up. There is a number that can be calculated to determine how likely a boat is to self right...

Capsize ratio... Higher the better.... Rate Your Boat-gosail.com

[builder dan]

not always my boat is an early ior quarter tonner its 24 foot long and has a beam of 10 foot 11 inches and only 400 kg of ballast,I have heard of 2 of these capsizing and neither of them self righted in both cases the skipper drowned, so these flat skimmers are not the sort of thing for crossing oceans in ,a narrower boat with a higher percentage of ballast would be a lot safer.

[fstbttms]

[David_Old_Jersey]

Yes. probably.

But it won't be pleasant, a good chance of losing the rig - and no guarantee that the boat and / or crew will survive the experience, even if she does self right.

Best avoided!

Unfortunately with Monohulls wishful thinking alone does not stop the laws of physics - for that you need a different hull configuration...........

[GordMay]

Greetings and welcome aboard the CF, lautzy.

[tropicalescape]

Originally Posted by fstbttms

What happened? If that boat would of had 4000 lbs of lead attached to the bottom it would have kept on going!?

[fstbttms]

Originally Posted by tropicalescape

What happened? If that boat would of had 4000 lbs of lead attached to the bottom it would have kept on going!?

That pic was taken during the inversion test the Open 60 "Oceanplanet" was required to pass before being allowed to race in the 2002 Around Alone race. The boat was very stable while upside down and in fact, owner/skipper Bruce Schwab (who was inside the boat during the 90 minute test) had to run back and forth athwartships on the cabin roof to get the boat to finally roll back upright.

I do not know what the bulb weighed, but I do know it was suspended from (or perched atop, in this orientation) a 12-foot keel.

[tropicalescape]

Originally Posted by fstbttms

That pic was taken during the inversion test the Open 60 "Oceanplanet" was required to pass before being allowed to race in the 2002 Around Alone race. The boat was very stable while upside down and in fact, owner/skipper Bruce Schwab (who was inside the boat during the 90 minute test) had to run back and forth athwartships on the cabin roof to get the boat to finally roll back upright.

I do not know what the keel bulb weighed, but I do know it was suspended (or perched atop, in this orientation) a 12-foot keel.

Cool..

[fstbttms]

Here's a video of the boat rolling back upright:

https://www.youtube.com/watch?v=LZcwoQoNVak

[valhalla360]

The question is not if it will self right but if it will go to the bottom.

If it doesn't sink it will likely pop back upright but if the main entry is open or a hatch gives way, most will be on the bottom.

[noelex 77]

Originally Posted by valhalla360

The question is not if it will self right but if it will go to the bottom.

If it doesn't sink it will likely pop back upright but if the main entry is open or a hatch gives way, most will be on the bottom.

Because the bottom is sealed not much water enters through an opening underwater. Air has to escape before much water will enter. You won't be cosy and dry, but inverted there is no great danger of sinking. Panicking and trying to swim out because of perceived danger of sinking is unwise.

[tropicalescape]

Originally Posted by noelex 77

Because the bottom is sealed not much water enters through an opening underwater. Air has to escape before much water will enter. You won't be cosy and dry, but inverted there is no great danger of sinking. Panicking and trying to swim out because of perceived danger of sinking is unwise.

I would perfer a boat that kept rolling to one that turns turtle,reminds me of an upside down Catamaran ...just a thought,no offense..

[noelex 77]

Originally Posted by tropicalescape

I would perfer a boat that kept rolling to one that turns turtle

Me too.

[valhalla360]

Originally Posted by noelex 77

Because the bottom is sealed not much water enters through an opening underwater. Air has to escape before much water will enter. You won't be cosy and dry, but inverted there is no great danger of sinking. Panicking and trying to swim out because of perceived danger of sinking is unwise.

That's true when the boat is full turtle... but before it gets to full turtle, those large openings have to be only partially submerged for a while. When partially submerged, your theory doesn't hold up.

An entry way that is 4' by 2' can let in hundreds of gallons per second. Even if it does manage to come back upright, it can be low enough in the water that following waves swamp the cockpit.

[barnakiel]

Originally Posted by tamicatana

maybe, but in any case the rig will be gone, and then the keel offers a lovely pendulum effect, unbalanced by the rig that is no longer there.

No. Not in any case. Many come back with they rig still up.

As you said, when the rig is gone the boat is more likely to get rolled over again.

b.