On the capsizing of multihulls…

There has been scuttlebutt about the inability of multihulls (catamarans and trimarans) to self-right after capsize for many decades. There’s also sometimes a belief that it’s very easy for them to turn turtle (as capsize can be called). The general gist of one side of the fanatics is:

  • once a multihulls gets turned over, you can’t get it back whereas a monohull can (not is) be designed, built, sailed and crewed to allow (semi-)automatic re-righting. So it’s far better to be on a monohull.

The “other” side generally responds with:

  • sure, once a multihull turns over she can’t be re-righted, but she almost always floats and provides a (uncomfortable!) platform to survive in until rescue. It’s also not easy at all to capsize a multihull, and the majority you see are racers and thus not generalisable.
    Also, almost all monohulls won’t re-right either as they aren’t designed, built, sailed AND crewed to do so and when turned usually go straight to the bottom of the ocean… and even if they do re-right, they have often lost their mast and ability to provide a stable platform for their crew to survive.

Do you think Ford or Holden is best? Cats or dogs? Catholicism or Hinduism?

Decisions have usually been made and sides taken: we have decided on a catamaran and are happy. But we can all still learn, and there have been quite a few scientific studies on the ability of multihulls to not turn over. I’ve quoted and copied what I find interesting pieces from a some publications here, and I’ll add more over time if you know of others (send me an email). We are obviously interested in respect of our vessel, so there’s some comments below for her.

TLDR: multihulls won’t capsize from non-breaking waves, and can probably handle breaking waves up to their beam.

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