BOURBON DOLPHIN PAGE

The offshore support industry is buzzing with the fall-out from the loss of the Bourbon Dolphin. As usual the media have been taking a shot describing the tragedy, but have had little to go on. This has resulted in graphics which in some cases are frankly laughable, and only in a few circumstances have people with knowledge had the opportunity of enlightening the general newspaper reading or web visiting public. 

It is probable that many visitors to this site have experience of anchor-handling and that others will at least know something about it, however, we can only speculate on the cause of the accident., as an investigation being conducted by the Norwegian Royal Commission is not yet complete and many fact remain unknown.

As one would expect, despite the lack of facts in the public domain, there is some information out there. We have the specification of the casualty on our site, even though it has been pulled from the Bourbon web pages. The Bourbon Dolphin was a unique vessel, the first Ulstein A102, a sort of compact version of the A101. It had 16000 bhp available which apparently gave it a bollard pull of 190 odd tonnes. It had a very large winch and so was thought generally suitable for deep water work. This particular mooring operation was taking place in a water depth of 1100 metres.  As well as two propellers in kort nozzles with high lift rudders, the ship was equipped with one tunnel thrusters and one azimuthing thruster forward and two tunnel thrusters aft. 

A public enquiry was conducted in Norway and some witness testimony has been translated into English. The following description is drawn from publicly available reports from the surviving Bourbon Dolphin crew members at that enquiry.

The most important witness was one of the two second mates, because he was driving the winch at the time of the accident. The master was at the ship’s controls. He had just relieved the mate who had been on the sticks since the 1200 shift change. The second mate described a situation where the Bourbon Dolphin was being unable to get back to the correct line, having pulled out 900 metres of rig chain, and deployed most of the 900 metres of additional chain it had been carrying. The complete length of chain was therefore partly supported by the Bourbon Dolphin and partly by the winch of the rig, the Transocean Rather. In these circumstances the tension which shows on the ship’s gauges is a combination of bollard pull, and chain weight, and according to the second mate the tensions on the ship’s readouts exceeded 300 tonnes at one point.

 The UT722 Highland Valour had been given the task of grappling the chain astern of the Bourbon Dolphin. If successful the Highland Valour would have taken some of the weight of the chain and this would have allowed the Bourbon Dolphin to take up a heading which would have got it back on line. Unfortunately, according to the witness there was a near collision between the two ships and during this the grapple fell off, so no progress was made. Also about this time the Chief Engineer called up to say that the starboard engines were overheating.

 Towards the time of the capsize there seem to have been a number of significant events. The starboard inner towing pin was lowered, and the chain allowed to slide across the stern, coming to rest against the port outer pin with some force, according to another witness. Also one of the ABs thought there had been a blackout , and lastly the second mate testified that after the master had relieved the mate, the latter started transferring ballast.  

According to the second mate, he had the job of writing the departure draft, and the departure GM in the log book. The draft was 6.5 metres and the GM was 0.26 metres. If you ask any experienced master in this business he will say that he would like there to be a GM of more than 1 metre.

The position of the chain seems to have occupied the media to a large extent, and hence the recollections of the witnesses are particularly important in this respect. Unfortunately the two who noticed the position of the chain disagree. The second mate recollected that as the ship went over to 90 degrees he saw the chain leading over the crash barrier, however the AB felt that the chain was trapped by the port outer pin.

 We have to emphasise that these are not facts. Most of the relevant evidence was provided by a young man who was on the bridge, although he had only qualified for the position he held at the end of last year. He is also recorded as having said that the starboard rudder was in the midships position and the port rudder was to starboard, however others have thought from the pictures of the ship upside down that the rudders were positioned so as to turn the ship to port, and and yet others have thought that both rudders were midships. We also have yet to hear from other witnesses, particularly the crew of the Highland Valour which was assisting the Dolphin in the operation at the time of the capsize.

 So having presented such information as I could glean from press and internet sources, I would invite those with a view to submit it by email to me, and as far as possible I will then post the suggestions or comments on this page, in an effort to at least dispel some of the myths, and to provide some guidance for those who find themselves doing similar work in the future.

Later addition - if you would like to read a summary a\nd comment on the report from the Norwegian Royal Commission click here

Last week the NMD published some guidance in advance of the findings of the Royal Commission.

Comments from our visitors

In my early career I was a little ignorant of stability. Only being an OS/DHU (DHU is a deck hand uncertified), on an UT704. It wasn’t till after I had passed my Mates CoC, and joined Gulf Offshore on the Kmar 404’s, that I had the chance to really see stability at work. I ended up serving as Chief Mate on four of these sister ships, with Gulf/Tidewater. During tank cleaning, repair or dry dock I took as much opportunity as possible to get inside these tanks. I feel that only then did I really understand what I was doing whilst pumping ballast/cargo etc. Also these vessels had a stability program which wasn’t hooked up to the UMAS tank tender system onboard, but was ‘long hand’ on the computer. I remember on this program there was the option to put the stern press in. This was like putting a weight on the roller. Now that was 8 years ago, when these vessels were new.  I’m sure that with technology nowadays you could get real time stern press, where the load cells on the winches are interfaced with the stability program.. (We did have it on the VS486’s, but the program never really worked that well, so we didn’t trust it) 

Although, I've left the AH's now, I still keep in touch with some of the guys. I did hear that the Bourbon Dolphin was low on fuel, and that the port tow pin was not up at the time. Was the 'Noman Posts' up i wonder? 

Do we know the condition of the anti-roll tank. I know a lot of people refer to this tank as a 'stability tank'. I think a lot more work should be done to teach people more about these tanks. They are good in the right conditions, but have huge free surface.

Also was the "maximum draught aft" (MDA) considered before the operation was undertaken? 

We won't be able to say if there are any similarities between this one and the Stevns Power just yet, but certainly looks like stability was not high on peoples risk assessment in both cases. 

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