Bayesian Sinking: Thoughts.

 I've commented way back about expensive yachts losing their keels when they shouldn't, now we have a supposedly (defined by the manufacturer) "unsinkable" super Yacht sinking.

Of course given extreme circumstances and a loss of displacement, anything can sink, but it seems strange that a super yacht of such a size can sink within seconds.

Surely there is enough buoyancy in such a large vessel to keep it afloat for at least a few minutes?

Well, it depends on how quickly the water was rushing in.

If, when the boat was knocked down there was a large enough opening that allowed the uncontrolled ingress of water, that would do it. Did the companionway not have a water tight door? Probably not. Was the companionway partially submerged when the boat was knocked down? If it was, isn't that a design flaw? Was there a garage door at the rear and was that left open? Were the internal doors to the garage left open? Were they even water-tight?

Any sailing ship can be knocked down in serious winds and the designer should account for that in the design.. Large open, unprotected spaces that allow the ingress of water should not be allowed. The ingress of water should be contained by water-tight doors and bulkheads. By all means have your grand entrance, but off that entrance everything should be ship-shape and closed off, so the vessel retains some buoyancy even if the grand saloon is flooded.

In the evening, when the watch is reduced, the ship should be dogged down tight and none of there garage/waterline access doors should be left open.

Emergency closing water tight doors should close when the vessel starts to flood.

There's lots of talk of the portlights being left open which caused the sinking. I doubt that very much as a portlight wouldn't be able to ship the amount of water to sink a vessel in seconds. 

And why would the portlights be left open? This is a multi-million dollar vessel, so I would assume it has climate control to keep the guests cool.

I'm not a conspiracy theorist. The fact his co-defendant in their court case also dies at the same weekend is more than likely a coincidence. 

But there are questions to be asked about super-yacht design and their ability to withstand extreme weather conditions, no matter how freakish or how unannounced. We all know that the sea is a cruel mistress. It can turn on you at any second. I lost my buddy Mick in April, lost overboard. I know how dangerous the sea is. I always had duplicate systems if not triplicate in place. Navigation was covered by my chart plotter, phone and tablet. My lifejacket was a high buoyancy auto-inflating version. If push came to shove and it was rough, I attached a harness and line to the big D-ring in the cockpit. 

Just as with the spate of keel losses a few years ago, the designs of super-yachts need to be investigated. Their lack of survivability needs to be understood, so prospective buyers can understand the risks involved. Just like with any other nautical purchase, the buyer needs to be informed. 

And to be honest, if you're chucking several millions at a yacht, you'd want it to look nice AND be able to stay afloat whatever the conditions. Wouldn't you?