Sinking of Yacht off Sicilian Coast

[Cesarina]

This is of course an absolutely tragic event.
I'm feeling a bit mean by saying this.........but why is it the headline topic on BBC news?
I genuinely feel sorry for those involved, but don't understand why it's the dominant news story?

@Daftasabroom

there are also LIDAR and RADAR wind field systems,

Yep, I’ve flown several aircraft types with a predictive windshear
function as part of the radar package (using Doppler shift to establish the windfield and detect any anomalies)…not completely fool proof because those radar systems didn’t work well in dry air but nice to have going to some parts of the world.

The whole issue of detection and warning of downbursts/windshear, and crew training on hopefully avoiding, and worse case escaping from the phenomenon have been a major deal in commercial aviation for quite a few decades now.

There’s obviously an imperative in terms of numbers of lives potentially exposed to try and reduce the threat to aviation to the lowest level possible. I think it is going to be interesting to see down the road if (and I know it’s a big if) a downburst is shown to be a factor in this accident if it leads to any rethinking of equipment or procedures in the maritime world or if the maths of any cost/benefit analysis won’t be as compelling.

They are stupidly heavy, so it's possible. I would have thought if they were a contributing factor it would be more likely that they were opened to allow people to exit the saloon. The patio doors are on the centreline and face aft so should never be a factor in any predictable scenario.

We also now know, or believe, that the port side door was closed. But also that the Engineer is under investigation for opening the door to the engine room.

I would be hugely surprised if it turned out that a single point of failure, either design or human, were responsible.

FLIR for those not familiar https://www.flir.co.uk/marine/recreational-boating/

I’m not convinced by the knockdown theories circulating as it doesn’t fit with survivor evidence thus far or with the CCTV.

The picture emerging from the investigation leaks is that a storm hit, the boat heeled around 20 - 45 deg, the crew ran around on deck, it heeled further and they were thrown in the water, they clambered back on but it sank. Equally one of the passengers who was on deck, said the boat “tilted” and she eventually found herself in the water. None have mentioned a knockdown at 70+ degrees.

Equally the leaked CCTV shows the boat heeling, then the lights go out - indicating the water may have flooded the generators causing the power to fail. It may be that the boat is listing not heeling.

NBC quotes Cutfield as saying the boat tilted by 45 degrees and stayed in that position for some time, then it suddenly fell completely to the right. Parker Eaton is quoted as saying that all doors and hatches were closed when the storm hit the boat, except one giving access to the engine room. That door was located on the side opposite to the tilting and so could not be a factor causing the sinking.

I’m not sure I’d be hanging my hat too much on any eyewitnesses, even those on board, being able to estimate number of degrees to a high level of accuracy…”tilt” then “tilt some more”/ “lot more” is fair enough.

Also TBH and as mentioned with reasons why, on the other thread on this I’m far from convinced anything at all should be “emerging from the investigation”…it’s really unfortunate and unfair on the victims and survivors that it is happening.

I’m not sure the precise degree of tilt is the most important aspect of the emerging narrative. It will always be approximate, even from the captain, but it can certainly be estimated. In the accounts thus far there have been no description of a sudden knockdown event, more a heel/list to a point of no return.

I don’t disagree about the leaking, but I think it’s inevitable.

Even on a normal yacht 20 or 30 degrees can feel well heeled, 45 feels pretty much a knockdown.

There is a report in the Times saying one of the tender doors was open as reported by a diver.

Possibly, the tenders are stored under the foredeck and usually double up as life saving so it may have been opened for that reason. The storage well should also be designed to fully flood and drain over the side.

Salvage work apparently scheduled to start on 20 April.

Dates confirmed for salvage of sunken 56m sailing yacht Bayesian

A diver has died during preliminary operations to recover British tech tycoon Mike Lynch's superyacht off Sicily's coast.

Police said the accident on Friday occurred while the 39-year-old diver was working underwater in Porticello.

The attempt to lift the yacht off the seabed is expected later this month and should help shed light on how Lynch's vessel disappeared into the sea.

Diver dies in preliminary operations to recover deceased tycoon Mike Lynch's sunken superyacht - ABC News

Oh that’s awful

That’s very sad.

That is sad, it is dangerous work.

MAIB interim report
https://www.gov.uk/maib-reports/foundering-of-the-yacht-bayesian-with-loss-of-7-lives

Article on the report

https://www.yachtingworld.com/all-latest-posts/what-happened-to-the-bayesian-first-official-report-records-events-on-night-of-fatal-sinking-157943

More of the crew were in grave danger and the actual moment of catastrophe came very quickly with particular gusts of near-hurricane winds.

@SheilaFentiman

Thankyou for that ..

Grim reading, as so often in accidents it looks like everything went from appearing pretty much normal to an absolute catastrophe in a very very short period of time....

It's sad as it seems like just another few minutes might have made the difference to getting the engines fired up and the ship turned or moved out of the wind as little.

@SheilaFentiman

Follow up question please...

Reading the report the apparent lack of accurate stability information has been mentioned..

In your opinion does this mean questions are going to be asked of the designer(s)/builders? I vaguely recall one of those involved in the build seemed very keen to throw the surviving crew and captain under the bus in the immediate aftermath of the accident.

Interested amateur rather than an expert :)

It looks like MAIB have to be quite constrained because there is also a criminal investigation, but were signalling hard that the crew and owner did not go against any published info they had. But if the designers didn't test or model enough weather/load/configuration scenarios - or worse, did but didn't list them - then I assume there will be fall out for them.

Thanks for providing. The article is succinct but quite detailed. It really sounds like there was absolutely nothing more that the crew could have done, in fact they and the survivors all acted extraordinarily heroically. My heart was in my mouth reading parts of it.

It’s pointing more towards design/ manufacturing as the cause really, isn’t it?

I would say the combination of design, condition of yacht and fairly extreme weather - the captain asked to be woken if the wind went above 20 knots, which he was, but the gust that tipped the yacht was over 70 knots.

The sails were furled and the centre board/swing keel was up (which was speculated about on here) but it seems that the manual only gave guidance regarding when the keel was down.

The University of Southampton's study concluded that the yacht couldn't recover from a tilt of 70.4 degrees in this configuration with a light loads. The manual had the angle (with keel down and sails free) as 84.3 degrees.

Bayesian’s SIB contained curves for the sailing conditions when at maximum load, contractual full load and in the light load condition. In all three of these conditions the centreboard had to be lowered. The respective angles of vanishing stability for the three conditions, recorded in the SIB, were 91.4°, 92.3° and 84.3°. The SIB contained Curves of Maximum Steady Heel Angle to Prevent Downflooding in Squalls. These curves provided a safe operating range for a sailing vessel, indicating the maximum heel angle it could withstand before there was a risk of downflooding occurring in a sudden gust or squall. The SIB did not contain such curves for when Bayesian was operating in the motoring condition where the centreboard was raised and no sails were up.

70degrees is a really low angle of stability - I have a small yacht and it’s angle is 130 degrees. Less than that and it will right itself like a wobble man toy. Not that I ever want to test that and prefer to remain upright at all times!

Scary reading. I’m glad the crew appear to be getting absolved of any blame.