56M Perini S/Y Bayesian Sinks During Palermo Storm

According to a recent article in Il Corriere della Sera, the 15 survivors claimed that the yacht tilted and then the bow sank vertically.

Wind load on mast is 0 @90° heel, as it varies with cosine of heel angle. Combined with an angle of vanishing stability (point at which righting moment = 0) of typically well over 100° you can see why sailing vessels generally don't capsize or sink during knockdown events.

And especially at anchor, with no sail up and secured by the bow only (i.e. not anchored fore and aft) it really is quite impossible to pin a vessel down to such a degree and for such length of time to cause catastrophic flooding.

The effect of a raised centreboard or lifting keel is to raise vessel VCG which reduces ultimate stability, certainly a contributing factor but far from a valid explanation.

I couldn't give a simple thumbs up or like, this deserves 1 hour of applause, at least!

Oh, the CEO of Italian Sea Group showed the weather forecast on TV...the storm was there...you could see the path

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Ok, Thanks. Sure, the wind load on the mast, when the mast is parallel with the water is zero. But what is the initial load. I went to wind load.com [sarcasm], but it was google, and threw in 120kts, hull dimensions of 184 feet x 16 feet, and mast dimension of 4 feet by 246 feet. Got a wind load of 80,500# on the mast & 207,800 on the hull for a total wind load of 287800 wind pound force. That's 143.9 short-tons. Hell, the damned boat is only 479 GT. . .

I know I'm a knuckle-dragger on this stuff, but after the boat is heeled over past 45 or 50 degrees, bad ju-ju is going to happen. And with the keel up, GZ is poor, if not inverted!

Any chance you could share the synopsis and local forecast including radar images with us for the day of the sinking?
(I did a search, but not very successful)
Thanks.

Didn’t you do a clever escape some years ago by running to the Bahamas when a major hurricane was approaching?

The 479 is the Tonnage, not the Displacement?
I looked all over for the displacement on this boat so as to guess the weight of the keel, no cigar, only Tonnage came up,

I'd say 500-550t would be a fair estimate based on similar vessels.

You'd actually be looking for the heeling moment, which is the wind force acting at some distance (height) depending on rig. You'd then also need the righting moment, which would require vessel displacement and righting arm (GZ) curve. Not sure any of this would help determine exactly what happened.

Btw 45° heel is not uncommon at all on smaller yachts and would not present a structural or stability problem for this 56m. Might be a bit uncomfortable though...

Agree about the 45° heel on smaller vessels, but on this big'n, things could be different. With the keel retracted, GM is small for comfort, GZ will therefore be minimal, and the ability to recover from a knock-down is compromised. I wonder if 45° is the peak? The following is only an example; not unique to Bayesian. . .

I want to see what the captain says in the investigation. . .

This graph would be representative of a motor vessel.

I would also like to hear what the Captain has to say, just to give him the benefit of the doubt and not to Monday Morning Quarterback him and his decisions from my lazy boy chair.

From my sailing days I remember stability curves showing a sailboat going over 115 degrees and still coming back up the right way, but with a fixed keel. (Pull the keel up and the stability may become negative, no recovery, and if you have a super long and heavy mast with the keep retracted, no recovery)

Ok, 525 tons, Metric probably?
20% of the displacement goes in the keel: 105 tons.. Sounds excessive even for a big boat like this: With the keel being retractable it can be less weight but stick further down, like 10 meters: More arm makes for more righting moment: Perhaps the retractable keel weighs 50 metric tons?
It sure would help to sink the boat in a hurry.
Hopefully this accident will be a learning experience for all Captains and Crews out there.

I admired your plan and it sure made you look clever.
You probably planned it good with fuel and supplies, etc.
Good plan..

Hope the owner gave you a bonus..

It's just the strangest most tragic story I have ever seen, especially with his co-indicted partner killed just before in a hit and run incident. Bad, bad, bad luck after victory.

That's in harmony with my suspicion of that forward recessed living area. Water tight door opened by crew exiting. Glass surround shattering. Heavy water digestion into the crew area. No recovery from that.