Self righting multihull?

Discussion in 'Multihulls' started by bjn, Feb 27, 2018.

  1. rob denney
    Joined: Feb 2005
    Posts: 652
    Likes: 43, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Good questions
    The inlet holes need to be well above the waterline on the lee side when the boat is flying a hull. The outlet holes can have flaps on them unless the false floor is above the hull flying waterline. The flaps can be gravity, pressure or crew activated.
    A pitchpole where the boat ended up bows down would be a problem. The self righting would not work. There are a couple of solutions i am playing with, just need time. However, I have pitchpoled my 7.5m test boat ELEMENTARRY – Harryproa a few times. It always ends up on it's side with the mast pointing upwind, even when the true wind is close to dead astern. Consequently, I am pretty confident that a pitchpole resulting in both bows going under would be pretty unusual (the boat would have to be well by the lee) and easily avoided by sailing a little higher.
    That is a function of the roughness of the rig on the model. Apart from foiling Bucket List, which is a test bed for the Volvo Proa , all harrys have unstayed masts. There is more on that boat and it's rig at
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