For those interested in more details about IMCO stability standards, White Fish Authority grants and trawlers built in the early seventies, the following link to a 1975 Parliamentary Debate on the Fishing Vessel ‘Silver Lining’ (& FV Trident) may be a worthwhile source of information:
http://hansard.millbanksystems.com/commons/1975/feb/10/fishing-vessel-silver-lining
9 comments:
Gadfly,
I remember reading this a few years ago and thinking everything was relatively clear cut but from the press report it is now not clear. Having changed weather significantly and static stability there is no reason to doubt this latest move.
The big problem is if I remember correctly from the OFI transcripts the DOT and WFA knew the vessel was not compliant therefore I would imagine it is in their utmost interest to prove non compliance did not contribute to the loss and secondly the need for compliance was a figment of someones imagination.
As a thought, an extract from the transcripts of the examination of Mr Sutherland of the WFA in the OFI
Day 4
Q . Tell me this, if you please : Why did the White Fish
Authority see fit to make it a requirement in all
specifications that the IMCO requirements should be
satisfied? A . We had been requested by the Department
of Trade in 1968 to apply this to fishing vessels which
were receiving grants from us, and we thought that as
this was a safety aspect towards the boat, we should apply
it.
Just a thought!
Best Regards RAJ
RAJ,
We agree with your assessment - in fact, the DOT actively promoted exactly the same arguments during their investigations into the loss of the Gaul.
What is also highly relevant is the actual date when they first became aware of Trident’s probable non-compliance with IMCO stability requirements - was this before or after the loss?
They knew that Silver Lining was non-compliant before Trident’s loss and also that she required significant modifications (the addition of ballast) to enable her to meet minimum stability standards. They also knew that Trident was a sister vessel to the Silver Lining and, as such, it would not take a quantum leap in deductive reasoning to suspect that Trident may have been similarly deficient.
It is unfortunate to note that in day 10 of the 1975 Official Transcripts, just when they start to talk about this very same point, pages 9, 10, 11 and 13 of the transcript seem to have been misplaced.
Best regards,
Gadfly
I would have thought that it did not need a "quantum leap in deductive reasoning"
From the Day 4 Page 54-55 Mr Sutherland again being examined
Q. You said you inspected the stability booklet on the Trident and you decided that it was a marginal case? A . Yes .
Q . So with very little more Trident would have met IMCO standards?
A . According to informal discussions I had had with the Department of Trade I understood it would.But you did say you decided that Trident was not 100%
I would seem someone somewhere had knowledge it was not compliant.
The slight confusion here is what someone defines as a "little more"
In the case of its sister ship Silver Lining I would suggest it took substantialy more than a "little"
Best Regards
Raj
RAJ,
If it takes 5-10 tons of ballast to obtain compliance with IMCO minimum standards, then on a vessel of Trident’s size, this is not really "marginal" or "little"
Following an investigation by Seafish into the stability of another similar (sister) vessel to the Trident (the Stanhope III), 6 tons of ballast were also required to achieve compliance with IMCO minimum standards (but on the basis of an assumed VCG of 0.9 x depth and subject to the results from an inclining experiment). See Seafish report:
http://www.seafish.org/resources/publications.asp
"Report of an Investigation into the Design and Stability Characteristics of Bute Slipdocks Vessel No. 485"
It is interesting to note that the Seafish data showed that, for vessels similar to Trident, the average lightship VCG was about 0.89D (para 5.2), while the ratio of lightship VCG to Depth on the Trident was about 0.95. - i.e. Trident’s VCG was higher than normal for vessels of her class
Other interesting quotes from OFI transcripts:
Mr Weyndling, DOT, day 3 page 23:
Q. Did you ever have any stability data relating to the Trident before you?
A. Never.
Q. So far as your sphere of influence is concerned, would you cover the Bute Slip Dock?
A. I would, yes.
Q. Do I take it then that no one in your Department received stability information in relation to the Trident?
A. That is correct.
And on page 27
Q. Would that particularly be so if in the stability data of the first vessel it appeared that the IMCO requirements had not been met, or would that not make any difference?
A. I think certainly if there was any doubt as to the stability of any ship one would be more inclined, or it would be more prudent to have another inclining experiment with a sister Ship: I would agree with that.
Best regards
Gadfly,
Thanks for your comments. I would like to add the Following from memory the Stanhope was indeed similar as oppossed to a sister ship and from the information Seafish.org it would appear still to be seriously deficient if table III was to be met it can be seen that that for the final condition the angle of max GZ occurs at 19 degrees.
The whole concept of compliance appears to in question I have heard that there can be relaxation although when reading through the IMCO ES168 ? it stated that the values are the minima.I t would therefore follow that it would take someone of experience and knowledge to grant such relaxation simply due to the fact that possible consequences would follow if it was found to be a costly error.
One arguement is of course what would the vessel have had to get done if the most onerous of the criteria were met and how would that have effected the vessel in its loss condition. I have also read in the OFI the arguments of how much fuel it had on board 5-8t and how it would effect compliance , this really is a red herring surely if the stability book does not state a minimum level of fuel then an owner would expect to be able to sail with 1t of fuel under the assumption his vessel is still compliance?
Best Regards
RAJ,
Surprisingly, our calculations show that the hull of the Stanhope III is a sister to that of Trident, rather than being just similar.
The results of the inclining test on Stanhope could be interesting in that it would provide a point of reference for the lightship particulars assumed for Trident.
Of course compliance in the worst sailing condition would probably also mean improved stability levels in the loss condition.
Regarding fuel, one of IMCO's standard conditions is with 10% fuel onboard (2.3 tons for Trident)and in general terms less fuel usually means lower stability.
If an operator often sails with only 1 ton of fuel on board, and maybe with no fish, then this should normally be included as a sailing condition in the stability booklet.
Regards
Gadfly,
Without ther relevant ducumentation at my disposal, I should possibly reserve my position on whether the Stanhope was indeed a sister or just similar. However I seem to recall it had a bulbous bow fitted albiet from the same plans however I will try and check this and confirm.
Best Regards RAJ
Gadfly,
One small point 10% of fuel for the Trident would have been ~ 1.3t as the 23t initial capacity was a mistake in the building process as was the freshwater tank which was undersized by 2t These faults were noted when tests on the Silver Lining were carried out in the summer of 74 prior to the loss of the Trident and the recommendations issued of no more than 12 or 13t of fuel to be carried on board the Trident I believe.
Best Regards
RAJ,
Point noted regarding the fuel capacity (23T capacity but with an operational restriction limiting filling to 13 tons only) that error in itself should have prompted the designer to re-draft and re-issue a new stability booklet for both vessels (with the fuel restriction red lined).
On the subject of ‘sisters’, our information shows that there is almost complete correspondence between the hydrostatics and KN stability curves of Trident and Stanhope III i.e. it looks as if the same hull design drawings were used for both vessels. It’s possible that there may be some small geometric differences between the two hulls, but even so, this would probably not be significant from a buoyancy/stability point of view.
Our information also indicates that a bulbous bow was not provided on Stanhope III however if you have access to more accurate info on this point (or on any other difference between the two hulls) we would be interested to hear.
Again, it would be interesting to find out what happened to the Stanhope III subsequently - what did the inclining experiment reveal regarding the Vertical Centre of Gravity? Were modifications carried out? How much ballast was required to satisfy the IMCO minima? – While Seafish and MCA files would, no doubt,:-) contain such info they would probably be reluctant to share it with others.
Best regards
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