Proteksan-Turquoise YOGI superyacht sinking investigation

The weather in the rescue video's didn't look very bad to me for a yacht of Yogi's size. It definately didn't look like it would cause stability issues where you'd have to run full power.

If they were steaming at full power, it's more likely the boat got delayed at the yard leaving and they were attempting to meet a demanding owner's schedule. But that is simply speculation.

What was the speed

Well, when I read what i've posted, i have realized i've missed the most important part. The crew was declaring a lower speed and consequently a lower load on the engines; the yard was contesting this by declaring, at the speed the crew declared, boat will not be able to cover the distance...

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I think, like Nilo, the key is the lower declared speed and engine loading contrasted with the facts.

I believe the yard was correct in their contesting the crews 14 knots and 60% load. The third party observed time and the actual distance showing the speed to be 16.7 knots and 100% load on the engines. And, this way easily checked and the yard caught it.

I believe the yard.

So the crew was not being forthcoming on this point... and despite ad hominen argument this is indication of lack of truth on the other issues.

I do not own a very large motor yacht like this being basically a "snail boat guy"... and sail boats work different than large multi-deck motor yachts. But I have significant naval vessel experience. I can see NO reason for the "balls to the wall" operation other than a stability issue. As the crew reported a lower speed and no circumstance was mentioned of a rush to get somewhere the only reason can be is stability. Someone mentioned stability increases with speed... I have noticed that on naval vessels particularly with following seas and wind in particular... all having fin stabilizers fitted too. Unless of course the conditions are so bad speed must be reduced for safety.

BUT if course corrections are needed, particularly abrupt, that very condition makes the boat, like we have here, more susceptible to extreme listing upon turning as the bow comes to the bottom of a trough.

This is almost exactly the same as an unexpected jibe/gybe in running in a broad reach with a canted keel and a sudden change in heading or wind direction... however, on a high windage and center of gravity motor yacht like we have hear... it is NOT as predictable as a sail boat with experienced crew who know the risks and results... yet can have the a jibe/gybe happen catching them off guard. Here the crew and master appeared not to realize the risks.

Seas were increasing and 3 meter or slightly better at time of accident were rough enough. The loss of the first engine was not abrupt enough and the boat had sufficient speed, momentum and steerage to stay up. If stability was not the best in the first place the loss of the second engine... when the stability issue was deteriorating might have been enough.

There was 20 minutes from first casualty to dire situation. The first being the loss of the engine due to cracking of exhaust coupling... . This time period is not really that long when crew is distracted and have not fully understood what is going on. An inexperienced crew it is short time. The lack of hand held communication makes this much shorter than it appears.

The loss of second engine due to overheating is suspicious... from crew statements there was no indication it should have been lost.

Just a thought.

Perhaps the second engine did not experience WOT until the first engine stopped and the throttle was accelerated on the second engine to compensate for the loss of power and stability with the first engine stopped.

Thus the second engine overheated, as a result.

Hi,

Cat have a power limiting section of the Engine Management Software.

Before an engine is stopped due to an overheat it will be slowed down from WOT if the temp keeps rising it will then be shutdown.

An unknown at thus stage was the engine rating.

To be run at 100% Power for a prolonged period they need to be A rated.

We also do not know when the last time the bilge level switches, engine mounted protection etc was tested and proven to operate.

The loss could very well be a number of things including the senior officers that each alone was not a recipe for disaster but combined were sufficient for the total loss of the yacht.

If the garage door was open, I'm guessing water can slowly enter this area...? Depending on how much water was getting in, this should have an impact on how the vessel reacts... I think usual handling characteristics would of been ampliied as the boat pitched and rolled, especially running with the waves. I can see the increase in speed justified to help stabilize the vessel.

Also, probably a daft question, but I don't know... engine water intakes... does those engines require them... if so where are they located....? Close to the waterline, or more towards the keel...?

karo1776, Fins are designed to work better with fluid running over them, thats why at anchor they aren't that flash, thats when the gyro come into play.
I can't see this type of vessel broaching, though possible. Slightly off track, if you watched the Volvo 70's running through the southern ocean a few series ago. They were running through at night, screening along at some great rate of knots with a 7deg aside bearing limit (as beyond the boat will washout) - while dodging icebergs.... Great stuff if your a sailor !

Far

statuory requirement

Hi Marmot

You have said :
The French International Registry of ships had a statutory requirement to submit the report of its investigation into the sinking of M/Y YOGI to the International Maritime Organization (IMO) within 6 months of the sinking.

Would you please give us a copy of this statuory requirement ?

Thanks

Thank you Marmot

Hi Marmot

Hope BEA mer inspectors have better to do !

Thank you for your prompt answer

and usefull link !

http://www.imo.org/blast/blastDataHe...filename=1.pdf

I read

Very serious casulties

Full investigation
report

To be provided at
the end of the
investigation in all
cases


Anyway i have found the information
The French International Registry of ships had a statutory requirement to submit the report of its investigation into the sinking of M/Y YOGI to the International Maritime Organization (IMO) within one year of the sinking.

annexes

Hi Marmot

Annexe 1 only...not annexes

Information to be
sent in
accordance with
the type of
casualty

Very serious
casualties

Annex 1 of the
attached
reporting format

To be provided
within 6 months
after the casualty
in all cases


Annexes 2 and 3
of the attached
reported format,
as well as other
relevant annexes

To be provided at
the end of the
investigation in all
cases

As you said

"I think we have just witnessed the worst that the superyacht industry and Flag States have to offer. It is a shameful situation."

Thank you for the help so many wrong informations are online.

what is more upsetting is that i feel the yard is becoming the scapegoat...

Yes, I did... and actually I would be more comfortable dealing with that in the great Volvo 70s than this yacht as I understand the situation. You cannot race a Volvo 70 (unless your an idiot) with an untrained and sloppy crew...

Here I believe the situation turned dire due to a sloppy and untrained crew...

I believe the yard was not an issue at all. But one can always pick the technical details to death and find some small... it could have been better fault... but that person is not paying for that luxury nor would I the time of construction... nothing is perfect but there is really no indication it was a construction issue.

The drip tank system installed in Genoa, providing a system of communicating tubes between the 3 aft compartments, might have been the « weak link » from an undetected leak to final instability ?

lobo

lightened pictures

Hi Nilo,

You're right !

YachtForums.Com > GENERAL YACHTING DISCUSSION > General Yachting Discussion > Proteksan & Turquoise Superyacht "Yogi" Sinks!
Page 6 posted from AMG
and 8 / BEA mer executive summary point 6

Bingo. Well put.

Facts which are clear...

1. The crew did give up the ship... too easily...

2. The crew did not operate the ship properly...

3. The crew was not up to the task...

As to the stability issue... it was caused in my opinion by facts 2 and 3.

Operation of the ship includes loading and balance issues; training; experience; knowledge of the systems; operation of the systems; maintenance, and importantly; decisions made by crew and captain.

The comments in my summarizes and surmises are based on not flaws of construction but flaws in operation of the ship learned from the report. I think something scary happened which spooked the crew otherwise why would senior staff almost immediately don survival suits. Despite nothing like this was mentioned in the report. This is why I have harped on the stability and possible broaching or something else. The reason for this suspicion is: why cover up the high speed run in deteriorating conditions when they had basically just begun a transit.

The yard pointing out the simple facts of speed and distance in opposition to the report should have been considered and investigated and referenced by the report... BY THE INVESTIGATORS.

The members of this forum have provided expert insight to the engine load situation, engine technical details, operation of engines, technical details of the beach clubs and operation of the ship which should have been obviously included in the report.

The drawing of the exhaust system of the engine installation showed care and thoughtfulness in engineering... so I doubt any real yard or construction issues. Certainly if the crew did not test and adequately report and have repaired issues under warrantee or trials and issues were not found that cannot be the yard's fault. That's what trial and the warrantee period are for to find issues. Things like bad welds or basic design, construction and functionality are the yard's purview by in large... but this report and empirically there is no indication of any such problem.

The cracking of the exhaust flange is not a huge issue. Yes, it lead to shutdown... but that is day to day stuff... not loss of ship stuff. These types of couplings and exhaust systems in general are areas to be under particular maintenance and inspection concern as part of the operation of the ship... lots of vibration, heat and fatigue. So are bilge pump and the like etc issues... as are seawater cooling systems... this is standard day to day stuff... to be handled as part of proper operation. These are always areas for routine inspection, maintenance and test and fix. I have been part of commissioning and initial operation crews of nuclear ships... and the first year or more is hell for little problems... that is part of the territory... but you cannot operate any ship for any length of time without such issues as mentioned in the report.

The fact this ship had made and been safely operated across oceans... proves its basic seaworthiness.

I am to the point of ignoring the whole mess... like it never happened... as it provides no lesson to be learned which is the reason everyone here is interested... to learn what happened to prevent it happening to them or the loss of life.

Avoiding yaw / broaching in following seas - Boat Design Forums

Some interesting comments herein...