Bourbon Dolphin capsizes

Yes. It seems that it is usual for those vessel to suffer equipment changes while they are being built. Not good, but if afterwards a proper inclining experiment is performed, stability calculations are done and the vessel found to satisfactorily comply with the requirements, then things should be OK.

What I'm atonished is about the question put to Mr. Moller by the commission:
"Do you know if the vessel's stability was assessed in view of the increase in weight?"
and his answer:
"No, but I assume the calculations are based on the actual weight of the boat."
They do not know....! Mr. Moller doesn't know....! He just assumes...!
Does this mean that an inclining experiment was not performed...? Unbelivable!

 

Reading this report and then reading the evidence again makes me wonder if I have been reading the same text,

The report was written by London Offshore Consultants (LOC) who have come to the conclusion that the ship satisfied the requirements laid down in the stability manual.

It draws no substantial conclusions about the cause of the accident but believes the accident is most likely due to a combination of several factors:

The weight of the 1800 metre long chain hanging over the stern roster pulled the ship down with the result that stability deteriorated;
Use of the roll reduction tank and partially filled ballast tanks as a result of transferring ballast water just before the accident;
Use of the thrusters can have caused a list;
Increased sideways force as a result of the inner starboard hawser pin being lowered just before the accident;
Water on the aft deck as a result of the list to port, large waves and the ship moving to port;
High sea;
That the engines stopped just before the accident. A possible corrective impulse from the thrusters would thereby have been made impossible;[/I]

The ship was an anchor handler which should have been stable with chain,144 tons load I think we agreed, over the roller.
The ballast transfer was started as a reaction to the vessel taking a "big shift to Port" about 10 mins before the accident.
The large sideways force that was showing 330 tons at the winch existed before the pin was lowered and the pin could only be lowered when this force was reduced by weather-cocking the vessel to the force, ie chain.
The water appeared on the deck when the pin was lowered, but was IMO also caused by the chain tension being reduced by the weather-cocking, power reduction??, and the resulting astern and portwise motion of the vessel.
The engines stopped after the accident had started and the vessel was being pulled down to Port.

It seems that the vessels poor stability may have been a factor, but no attempt has been made yet to address the cause of the excess loading in the chain. We know that she had been pushed sideways, by wind and tide, for a considerable distance while all the time thrusting and driving in an attempt to get back to the line. I have seen strong gales of winds breaking ships dock mooring ropes more than once so there is a potential for strong loads although the weather on the day did not seem that bad. Could using the power to hold her beam-on to wind and tide while the chain was holding her by the stern have created a position that locked her into an inescapable situation?
The reported turn to starboard immediately before the capsize, that lowered the chain tension, would have released these locked forces in an astern and portside rush that was more than she could handle.

Murdo

 

Murdo, this has been thrashed around here since April, have you read all this forum? frankly I soon realised that all the theorising, which once again goes around and around and around, is no darned good whatsoever It is all assumption
its kinda like this, you have a race yacht, you push her and one day you find her limits, that is you capsize
Well sad, tragically they found BD,s limits

 

The problem, Stu, is to know if such limits were the right ones.
Cheers.

 

Lazeyjack,
I hope you did not mean to be so patronising as your words feel to me. I may not have all your knowledge, but I have been there and round the corner. There are no arguments, theories or assumptions in anything that I have written. There are facts based on witness testimony and the simpler laws of physics. Everything else ends in a question mark because it is left as a question for others to agree, disagree or dismiss as they see fit.
As long as no one asks any questions, accidents like this will be whitewashed and other sailors will suffer similar fates

Murdo

 

Lazeyjack, Murdo your both right, as they say Laze "**** happens" and happen it will! BUT if we accept that we are dooming more sailors to a watery grave! As an ex AHTS mate of some 17 years standing please allow me to say that we must ask and ask again why these things happen, and do something about them! otherwise all those lives lost have been in vain (yes I've lost friends out there, more than I'd like to think about, its part of the job, but for their sakes the people with the know how must keep asking the questions! and getting the answers, hopefully! and if they don't, us with less knowledge must keep pushing - if that saves one life it's worth it! and I don't really care who's, he's a seaman thats all that matters! Thank you!)

 

Again: In my opinion what is relevant to these forums' purposes (they are design oriented ones) is to try to know if the accident has a design and/or building origin or not. Seamanship and crew performance, although essential to be brought into the picture to understand what happened, absolutely, is somewhat secondary to this thread purposes.

Little by little, going round and round an step further each turn, sharing the relevant info everyone finds out here and there, or even producing it by some of the posters, guessing things, making assumptions, etc, this thread has been bringing some technical light about the accident to us, the ones who do not have all the info, so we can better understand what and why happened. Or even rising more questions. A most interesting learning exercise and very adequate to Boatdesign.net purposes, at least to me.

The one who is not interested in this kind of discussion has a very easy thing to do....

Cheers.

 

No offence was meant, I was merely trying to point out that we seem to be covering the same ground Sorry I upset you, anyways, I am not qualified to do the maths as I have said many times, and I'm certainly without practical experience on these ships
I don't know if I missed something, but why did the mains stop, was it because they had been in the red for a long time?

 

Thanks Lazeyjack,
I was not offended, maybe a bit upset but that's nothing new.
There is a memorial near my home with the names of many friends and colleagues who perished in a previous Offshore disaster. Those of us who had been engaged in the hook-up and subsequent maintenance and modification projects on the platform all new that they were working in an unsafe situation. The name was synonymous with danger in all our minds but we did nothing about it except talk among ourselves. When the replacement platform was being installed we held a service on the site on the 2nd anniversary of the tragedy. We all felt so guilty.
Getting back to your question about the mains stopping, the bridge survivor said that the engineer rang the bridge after the boat had started taking water on the deck. Three things had happened about this time.
Firstly the lowering of the tension by changing course. Any drop in the tension would have shortened the horizontal dimension of the chain and the vessel would have had to be moving in the direction of the chain.
Secondly, the load was transferred to the port side.
Thirdly, the starboard engines stopped.
Did all three happen at about the same time, the engines stopped by a safety system, or did the engines stop as a result of the first two and the resultant roll to port and with water being scooped up onto the deck? It is unlikely that we will ever know for certain.
I wonder if a mini-ROV could get this information by recording what had tripped on the engine controls??

Murdo

 

I still believe that the engines stopping was a major factor in the loss of stability. We just finished working some anchors in shallow water and by going from 100 percent power to zero I was able to get about 4 knots astern in only 150' of water. You can imagine how fast the BD must have been sucked back. Add some water on deck (and loss of waterplane area) and I can see a major stability issue developing.

I really have to wonder how other AHTS vessels would react if they went from 100 percent power to zero. It is a scary thought to me that a vessel may be designed where they have to rely on a dynamic force to counteract potentially fatal forces brought about by normal operations.

 

ok, I,m not trying to make an ENQUIRY here but having a curious wondering, Is it possibel the main stalled, like drooped awy to stall point, say low fuel press or something

 

You may well be right, but I can't stop thinking that a similar unopposed astern, port quarter pull was released by the turn to starboard that is mentioned in the early eye witness reports. The main props would have been on restricted power as the bulk of the power was going to the thrusters. If this was the case and if no extra thrust was applied to the main props before the manoevre, this unopposed force could have been as high as 200 tons, I'm guestimating here.
I think you are right to be worried about what happens in a power loss situation while under tension, and I would add other unopposed released energies as well

Murdo

 

Bourbon Offshore Norway reported that the Anchor Handling Tug Supply Bourbon Dolphin has capsized while in operation 75 nautical miles North, West Shetland Islands with 15 people on board. According to Neville Davis, Rescue Coordination Center Manager, Shetland coastguards: "So far, 10 persons have been recovered. We will continue working with the assets available to try and locate the missing crew".
Of the 10 recovered three are confirmed dead, and reportedly none of the seven others were seriously wounded.
The company emergency response team in Norway, supported by Bourbon emergency management team in Marseilles is, according to plans, assessing the different available information.
New Information will be released as soon as the relevant elements will be available and fully checked.
Bourbon is in close contact with the families and is doing all it can for them and a Bourbon support team is in place at Bourbon Offshore Norway head office.
Jacques de Chateauvieux, CEO of Bourbon, and Christian Lefevre, Deputy CEO of Bourbon and Bourbon Offshore CEO will arrive at Bourbon Offshore Norway Headquarters during the afternoon.
The company emergency response team in Norway, supported by Bourbon emergency management team in Marseilles is, according to the Safety Management System plan, assessing the information available at this time
04/13/2007---Marine technology reporter web site

 

Saeedeh,

Thank you. Yes that was the initial announcement of the tragedy we have been discussing, which happened in April of this year.

 

I agree. They knew the overweight condition was from added weight of equipment, yet a key person, knowing he is to testifiy about the ship's construction, doesn't know if new stability calcs were done after the extra weight issue was discovered?? Unbelievable.