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It's possible to come close. This is a U.S Coast Guard response boat being tested.[1] Using big straps and winches, it was pulled all the way over until it was

It's possible to come close. This is a U.S Coast Guard response boat being tested.[1] Using big straps and winches, it was pulled all the way over until it was upside down. It immediately righted itself. Most modern rescue boats and lifeboats are self-righting. With proper hull design and enough foam flotation blocks in the right places, boats can be made to right themselves. Unless the boat is chopped into bits, it will float. It's worth it for those classes of vessels. Their job is to handle very rough conditions. The price of such extreme stability is a rough ride. Self-righting yachts exist.[2] But they look like rescue boats with nicer interiors. Many recreational sailboats have enough flotation to survive 90 degrees of roll, with the sails flat on the water. This is called a "knockdown". In small craft, it's usually embarrassing but not a disaster. Larger sailing craft are usually built to avoid rolling that far. There's a conflict between luxury and seaworthyness. The things you want for rough conditions, such as high freeboard and few openings, conflict with what people want in a luxury craft. Bayesian apparently couldn't go past 45 degrees without water pouring in. A stupidly tall and heavy mast allowed wind to push it that far over with no sails raised. [1] https://www.youtube.com/watch?v=jXF-TjOjD5k https://www.youtube.com/watch?v=jXF-TjOjD5k [2] https://www.youtube.com/watch?v=CqVItm0jfE0 https://www.youtube.com/watch?v=CqVItm0jfE0

kragen 2y ago
Your comment, if correct, is far better than the NYT article, explaining what happened and why in five short paragraphs.
- Animats 2y ago
  That's just an overview. The real question is, how did a heavily ballasted sailboat with no sails raised get knocked down by wind alone? Other boats nearby did not report large waves. Nobody has really answered that yet.
jabl 2y ago
> Self-righting yachts exist.[2] But they look like rescue boats with nicer interiors. > Many recreational sailboats have enough flotation to survive 90 degrees of roll, with the sails flat on the water. This is called a "knockdown". In small craft, it's usually embarrassing but not a disaster. Larger sailing craft are usually built to avoid rolling that far. Offshore racing rules tend to specify things like minimum angle of vanishing stability (AVS), they tend to be around 130 degrees. Similarly yachts sold in the EU must fulfill ISO 12217-2 which, AFAIU, also requires a minimum AVS of 130 degrees. Not sure if that applies to the Bayesian, it might be old or big enough to be exempt from these rules.
- Animats 2y ago
  A former captain of the Bayesian wrote a 2-page note.[1] "The downflooding angle for Bayesian was around 40-45 degrees". The Angle of Vanishing Stability was, he says, in the 75 to 90 degree range, depending on whether the moveable keel was down. The movable keel, he writes, weighed 60 tons. It had to be down when sails were raised, but usually wouldn't be lowered in harbor. There were 200 tons of fixed keel ballast. [1] https://www.linkedin.com/posts/stephen-edwards-78539147_some-notes-on-bayesian-activity-7233792846770659328-JLgI/ https://www.linkedin.com/posts/stephen-edwards-78539147_some...
  - jabl 2y ago
    Yes, I saw that writeup linked to in the discussion earlier. I'm no naval architect, but I'd imagine for such a big boat an AVS of 90 degrees sounds reasonable. But a downflooding angle of only 40-45 degrees, that's just bonkers.
    - Animats 2y ago
      The former captain says that's the angle at which the generator and HVAC air intakes flood. Those are closeable if the equipment is turned off. The US Coast Guard definition is "Downflooding angle means the static angle from the intersection of the vessel's centerline and the waterline in calm water to the first opening that cannot be closed weathertight and through which downflooding can occur." So downflooding angle safety certification for bad weather apparently assumes the boat being in a buttoned-up condition. But, buttoned up, the yacht has no air conditioning or non-battery power. One article mentions that lowering the moveable keel for more stability results in a much noisier environment below decks. So, rigged fully for bad weather, it ceases to be a luxury yacht. The ship was in harbor, at anchor. That's not usually a situation in which a ship is rigged for worst case conditions. Here's a picture of the infamous mast.[1] It's not just a pole. There's a lot of structure with surface area. Nobody seems to have anticipated that wind on the bare mast system was enough to knock the boat down. But it was. [1] https://www.msn.com/en-us/money/markets/how-the-defining-feature-of-30-000-000-superyacht-could-have-been-the-reason-it-sank/ar-AA1tgVHU https://www.msn.com/en-us/money/markets/how-the-defining-fea...

kragen 2y ago

Your comment, if correct, is far better than the NYT article, explaining what happened and why in five short paragraphs.

Animats 2y ago
That's just an overview. The real question is, how did a heavily ballasted sailboat with no sails raised get knocked down by wind alone? Other boats nearby did not report large waves. Nobody has really answered that yet.

jabl 2y ago

> Self-righting yachts exist.[2] But they look like rescue boats with nicer interiors. > Many recreational sailboats have enough flotation to survive 90 degrees of roll, with the sails flat on the water. This is called a "knockdown". In small craft, it's usually embarrassing but not a disaster. Larger sailing craft are usually built to avoid rolling that far. Offshore racing rules tend to specify things like minimum angle of vanishing stability (AVS), they tend to be around 130 degrees. Similarly yachts sold in the EU must fulfill ISO 12217-2 which, AFAIU, also requires a minimum AVS of 130 degrees. Not sure if that applies to the Bayesian, it might be old or big enough to be exempt from these rules.

Animats 2y ago
A former captain of the Bayesian wrote a 2-page note.[1] "The downflooding angle for Bayesian was around 40-45 degrees". The Angle of Vanishing Stability was, he says, in the 75 to 90 degree range, depending on whether the moveable keel was down. The movable keel, he writes, weighed 60 tons. It had to be down when sails were raised, but usually wouldn't be lowered in harbor. There were 200 tons of fixed keel ballast. [1] https://www.linkedin.com/posts/stephen-edwards-78539147_some-notes-on-bayesian-activity-7233792846770659328-JLgI/ https://www.linkedin.com/posts/stephen-edwards-78539147_some...
- jabl 2y ago
  Yes, I saw that writeup linked to in the discussion earlier. I'm no naval architect, but I'd imagine for such a big boat an AVS of 90 degrees sounds reasonable. But a downflooding angle of only 40-45 degrees, that's just bonkers.
  - Animats 2y ago
    The former captain says that's the angle at which the generator and HVAC air intakes flood. Those are closeable if the equipment is turned off. The US Coast Guard definition is "Downflooding angle means the static angle from the intersection of the vessel's centerline and the waterline in calm water to the first opening that cannot be closed weathertight and through which downflooding can occur." So downflooding angle safety certification for bad weather apparently assumes the boat being in a buttoned-up condition. But, buttoned up, the yacht has no air conditioning or non-battery power. One article mentions that lowering the moveable keel for more stability results in a much noisier environment below decks. So, rigged fully for bad weather, it ceases to be a luxury yacht. The ship was in harbor, at anchor. That's not usually a situation in which a ship is rigged for worst case conditions. Here's a picture of the infamous mast.[1] It's not just a pole. There's a lot of structure with surface area. Nobody seems to have anticipated that wind on the bare mast system was enough to knock the boat down. But it was. [1] https://www.msn.com/en-us/money/markets/how-the-defining-feature-of-30-000-000-superyacht-could-have-been-the-reason-it-sank/ar-AA1tgVHU https://www.msn.com/en-us/money/markets/how-the-defining-fea...