In an earlier post we gave an overview on how the re-opened Trident casualty investigation (RFI) was being conducted and managed by the Advocate General towards an outcome that would be preferred by at least one of the departments in our current Government (the DfT).
Recently we have learnt that the JPE (the RFI’s Joint Panel of Experts) had also taken it upon themselves to rewrite the official records of Trident’s intact stability.
Work done:
The JPE have changed the official DOT lightship particulars for Trident (from those used in the original investigation):
Original investigation (OFI) 1975
Lightship displacement[1] = 149.83 tonnes (147.46 imperial tons)
VCG[2] position = 3.197m above keel (10.487 feet)
LCG[3] position = 9.971m forward of the rudder stock (3.525 feet aft of amidships)
Re-opened investigation (RFI) 2010
Lightship displacement = 153.01 tonnes
VCG position = 3.18m above keel
LCG position = 9.95m forward of the rudder stock
They have also modified the weights of the items that she was assumed to be carrying on the day of her last voyage (the original figures can be seen in the NMI/Morrall testing report page 13 and in the report of the original investigation - condition A2):
- They increased the amount of fuel she was carrying by 1.75 tonnes to 6.75 tonnes
- They doubled the amount of fresh water on board to 3 tonnes
- They reduced the amount of stores in the upper focsle space from 1.5 tonnes to 0.45 tonnes and removed 1 tonne of stores from the lower focsle space
- They reduced the weight of the fish boxes in the hold from 3.37 tonnes to 2.4 tonnes
- They reduced the weight of the lube oil drums in the engine room by 20kg
- They reduced the weight of fishing nets from 3.6 tonnes to 3 tonnes
- They increased the weight of the gallows chain from 0.27 to 0.45 tonnes
- They removed the ‘dog rope’
- They increased the amount of engine room stores by 100kg
- They increased the amount allowed for the crew’s effects by 90kg
In brief, the effect of the JPE’s modifications has been to increase Trident’s notional stability reserves[4] by about 10% for her final sailing and loss condition.
If we look at the stability of the Trident in both the original and the JPE-modified conditions we can see that in her original condition, Trident is clearly non-compliant with IMCO minimum stability criteria, however, after the JPE modifications have been applied, her stability improves to the point where she only marginally fails to meet the IMCO minima:
What were the motives behind the JPE’s actions?
1. To ‘update’ our official records to indicate that, contrary to the evidence contained in the report of the 1975 formal investigation and in the 1976 NMI/Morrall report, the Trident’s stability at the time of her loss 'complied substantially with IMCO'[5] minimum standards, and that, therefore, non-compliance was not a factor in her loss.
(RFI Transcript for 12 July 2010 – Advocate General page 102:)
2. To request the Sheriff to dismiss the conclusions from the original 1975 formal investigation and the subsequent model tests carried out NMI/Morrall in 1976;
(RFI Transcript for 12 July 2010, page 105:)
3. And finally to oblige the Sheriff to conclude:
(RFI Transcript for 12 July 2010, page 74)
Our conclusion
The callous way in which the current investigation into the tragic loss of the Trident and her seven crew members has been scripted by the DfT and conducted by the AG towards a pre-determined outcome reveals the depths that our Government, and those it employs, will stoop in order to maintain policies that, regardless of their warped perception of the public interest, they know are both unjust and unlawful.
This is nothing less than a national disgrace
An extended pdf version of this article is available HERE.
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[1] Lightship displacement = the floating weight of the empty ship
[2] VCG = the position of the vertical centre of gravity of the ship’s weight
[3] LCG = the position of the longitudinal centre of gravity of the ship’s weight
[4] Note: In 1975, the Court’s experts carried out a very comprehensive and careful investigation into Trident’s stability characteristics - in terms of ascertaining her empty hull weight, position of centre of gravity and the items of fishing gear, fuel, water and stores she was carrying onboard at the time of her loss. There is no substantive reason or factual basis to justify the changes that have now been carried out by the JPE.
[5] This was the stated position of the DOT throughout the 1975 Formal Investigation
6 comments:
Gadfly,
I see you have quoted the council for the inquiry as follows
She said “ there is no reliable evidence to support a finding that the loss of the Trident was caused by a deficiency in her design stability as measured by the extent of compliance or non compliance with the recommended IMCOs intact stability criteria”
Is council for the inquiry trying to suggest as vessel departs from IMCO it becomes more stable surely it is the converse that is generally true? i the evidence that was produced which she appears to classify as unreliable can only be NMI and the tests with Marin including 7.5 tons ballast in which case as I posted a reply earlier the inquiry is in danger of being left with a model of a vessel capsizing without any additional information all this at the bargain price of £6+ Million. I do however believe that the department will look upon this as money well spent.
The real reason I believe that she appears to have found no reliable evidence with regards to IMCO is that they quite simply did not look for it.
The statement in general is rather hard to decipher possibly without reading it in its entire context, if one is to take it apart e.g. "design stability as measured by the extent of compliance"
Is she suggesting that the design stability was something else from the actual stability? the inclusion of the word design appears to superfluous otherwise
Best Regards
RAJ
RAJ,
Certainly if the JPE/RFI had wanted to examine the Trident’s propensity to capsize in the range of sea conditions that were possible on the day of her loss, with variable levels of stability and with different load combinations onboard[1], then this would have been a very straightforward exercise for MARIN (or better still a UK-based test facility).
However, this type of testing would probably have yielded the 'wrong sort of evidence' and, as you imply, from their viewpoint, it would obviously be better to spend £6m and get the 'right' answer than spend (say) £100,000 in the UK and arrive at the 'wrong' conclusion or, even worse still, not spend any money at all and draw conclusions from the results of previous UK research.
We agree that the sentence which includes the phrase "… deficiency in her design stability.." is a bit of a mouthful, probably, in plain English, she means something like:
"Nothing arising from this RFI will provide you with proof that the design of Trident was faulty."
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[1] In fact a range of tests just like those that were completed by the NMI in 1976.
best regards,
Gadfly,
I cannot disagree with your assessment . The final conclusions from the JPE are in my opinion equally " a bit of a moUthful"
We have had the earlier reported un-specifiable "specific sea-keeping" in the initial conclusion however the JPE also had a second part to the conclusion which was added at a very late stage possibly inserted at the clients request? which reads
In light of the passing of the passing of 35 years from the time of the loss to the finalisation of this report and given the considerable changes to navigational communication life saving and fire fighting equipment and the changes of the methods and testing of ship design the JPE are of the view that any safety lessons that could have learned have been superseded by the passage of time.
The first part down to and including fire fighting equipment is in my opinion totally irrelevant to the is inquiry due to the type of the loss other vessels have foundered sadly with loss of life in recent times and unfortunately none of these items have prevented it.
The second part which includes testing methods I do however think is highly relevant having recently been serving on a vessel which had undergone structural modifications I was slightly surprised that the vessel had to undergo an inclining test to verify the design modifications , it therefore seems the humble inclining experiment is still not so out dated and irrelevant as the JPE would have us believe.
Does this passage infer that there was lessons learned from the loss of the Trident if so what were they?
Best REgards
RAJ
RAJ,
We were stunned to see what the JPE has written as the second part of their conclusion and will be posting an article about this in the near future.
It goes without saying that if you are not seriously looking for a problem then you will probably not find one and if you have not found a problem then what is there to fix?
Regards
Gadfly,
Would it not be the be more of a case of you don`t have to look for a problem if it has already been found ? or perhaps that too would be rather "inconvenient"
In my opinion if there was lessons learned from the loss, for example "its best to incline a vessel when it is not a proven design" or perhaps" best adhere to IMCO recommendations" then I think that the RFI should share such such lessons after all its the public who are "footing" the bill.
On the subject of inclining tests and the JPE who on the face of it were rather reluctant to place much importance on the inclining test and the the possible importance of VCG I was rather surprised on reading the following passage from Strathclyde university website which appears to be connected to Prof. MacFarlane who was on the JPE
The extract is in connection with something called the MOSIS system
"it is easy to check the weight of a vessel by reading draughts and comparing with the known properties. It is not as easy to check the position of the vertical centre of gravity (VCG) and yet this dominates stability. To control something you need to be able to measure it and yet the VCG cannot be regularly measured – how can it be controlled?
The VCG position can be estimated by moving a weight to produce a known overturning moment. Knowing the restoring properties (buoyancy) of the vessel and measuring the equilibrium angle that the vessel lies at, the VCG position can be calculated. This is an Inclining Test and it is done inshore in still water and free of mooring restraints to achieve accuracy. It costs money and loses productive time.
So it would appear that if finding the VCG of a vessel is so important then why was this not done on the Trident and in addition it appears that the Professor appears to know about the importance of finding this with an inclining test of some description.
How was it then that none of the JPE seem to attach much importance to an inclining experiment?
Best Regards RAJ
RAJ,
"…….changes of the methods and testing of ship design…." To tell you the truth we are not aware of any significant changes to the methods of testing the design of fishing vessels or the majority of merchant vessels. We don’t suppose it would be any good asking the JPE to tell us what these new methods are – probably they would also turn out to be specific but un-specifiable.
The 'humble inclining experiment' still forms an essential and critical part of the tests that any new or modified ship has to undergo before it can put to sea with full set of safety certificates. Vessels that are in service also need to be inclined periodically to check that their stability has not deteriorated. The test is specified in IMO maritime safety legislation for most seagoing vessel types and may only be waived when accurate sister ship data is available or when its results are not critical (e.g catamaran) for achieving safe levels of stability (IMO compliance).
The test provides an accurate reality check on a designer’s estimates for VCG and will often indicate when errors have been made. It also enables stability levels to be calculated and verified against the stability criteria that are appropriate for the vessel’s type, size and service (for 'intact', 'damage' and 'probabilistic' types of stability).
In 2010, the inclining experiment still remains the best way of finding out what a vessel’s real Vertical Centre of Gravity actually is (and the VCG, as everyone knows, is a critical parameter which influences stability, sea-keeping and vessel motions).
Best regards
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