The combined effects of the Gaul’s stability shortfalls and duff and offal chute design faults

The principal finding of the 2004 Re-opened Formal Investigation (RFI) into the loss of the Gaul was that flooding of the factory space had occurred through two hull openings in the side of the vessel and that it was probable that this ingress of water led to the capsize and sinking of the Gaul.

Up until December of last year this blog focussed on a number of obvious design faults and flaws in the construction of the duff and offal chutes on the Gaul, and criticised the conduct and outcome of the 2004 RFI which, ignoring these facts had concluded that the flooding and loss of the vessel had been caused by the crew’s failure to close the inner covers of the duff and offal chute hull openings. Recently, however, we have added a summary of the results of a separate investigation, which has revealed significant stability shortfalls (on IMCO’s minimum stability standards [*]) that would have affected the Gaul in a number of her normal operating conditions.

As far the capsize and loss of the vessel is concerned, it should be noted that, while the stability shortfalls and flooding of the factory space through the duff and offal hull openings (facilitated by defective closing arrangements) are two different matters, they do not suggest differing causes for the loss of the Gaul; in fact, the impact of each is complementary to the chain of events which led to the loss of the vessel.

The stability reserves of a trawler may be regarded as a finite but variable quantity, dependent upon the vessel’s condition of loading, disposition of fuel, water etc. If seawater is allowed to flood into the hull, the stability of that trawler is reduced and the possibility of capsizes rises.
The 2004 RFI concluded that an ingress of about 100 tonnes of seawater (entering through her duff and offal chute openings) would have been necessary before the Gaul’s stability reserves would have been depleted to a level where capsize was probable in the weather the vessel encountered.
Our investigation has shown that, because the Gaul’s actual stability reserves were initially much lower than those assumed by the RFI, capsize would have been probable after only a modest ingress of seawater.

However, regardless of the design faults in the chutes’ closing arrangements, the Gaul’s stability problems and their combined effect on the safety of the vessel, the 2004 RFI was still content to attribute her loss to a failure on the part of the crew to close and secure the duff and offal lids during the storm they encountered on 8 February 1974.
Their conclusion, however, appears now extremely far-fetched.
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[*] One of the most important safety standards for a sea-going trawler is that it should meet the IMCO minimum stability criteria, however:

- Compliance with the IMCO minimum stability standard does not guarantee that a trawler will be safe from capsize in severe weather
- A trawler having stability reserves that significantly exceed the IMCO minimum standard is unlikely to capsize in severe weather
- Non-compliance with the IMCO minimum stability standard does not automatically mean that a trawler is likely to capsize in severe weather
- A trawler having stability reserves that fall significantly below the IMCO minimum standard is likely to capsize in severe weather.

The Stability of the Trawler Gaul (part 2)

36 years have passed since the trawler Gaul sank in the Barents Sea on the 8th of February 1974 and 5 years since the Re-opened Formal Investigation into its loss laid the blame for the tragedy with her crew. Today, by way of remembrance, we are going to reveal a few more facts about the stability of the trawler Gaul.

On 5 December 1972 the Department of Trade (DOT) finally completed their examination of the stability of the Ranger Castor (renamed Gaul in 1973) and issued their official stability certificate:

This document was meant to attest that the Gaul’s reserves of stability in her foreseeable sailing conditions had been examined by the DOT and found to satisfy IMCO’s minimum stability standards.

Unfortunately, the stability documentation that had been examined by the DOT prior to their certification of the Gaul contained a number of basic errors and, what is more, it did not reflect the fact that two of Gaul’s seawater ballast tanks had been converted to carry fuel oil. The effects of this conversion were, however, significant for the vessel’s stability because they meant that she could no longer meet the IMCO’s minimum stability standards in all of her operating conditions.

The Original Formal Investigation (OFI) September - October 1974

In the original formal investigation, the Builders, the Owners and the DOT were all able to draw upon the testimony of their expert witnesses who were well versed in ship stability matters; unfortunately, the same cannot be said for the relatives of the deceased who, instead, had to rely upon the integrity of the Court.

The loss of the Gaul, obviously, raised a number of questions concerning the safety of her remaining sister vessels, and, therefore, a part of the 1974 OFI was spent in considering the safety of the Ranger C class vessels [1] as a whole.
The effect of the ballast tank conversion on the stability of the Ranger vessels was examined in some depth, leading to the agreed view [2] that, even if these vessels sailed with fuel oil (instead of water ballast) in their no 2 Double Bottom tanks, the IMCO minimum stability criteria would still be met provided operational measures (i.e. where the ships’ staff were instructed on the sequence of fuel tank usage) were implemented, and that these would be sufficient to ensure the safety of the remaining vessels.

An extract from the transcripts of evidence for Day 12 OFI:

(Mr Ward represented the Gaul’s builders - Brooke Marine and Mr Gilfillan was an independent consultant Naval Architect who had been engaged by the Gaul’s owners to examine the safety of their Ranger Class vessels.
In the above transcript they were discussing the content of a letter concerning fuel tank usage that had been sent by the owners, shortly after the Gaul was lost, to the skipper of the Kelt, a sister vessel to the Gaul.)

This operational measure (i.e. that the No.2 double bottom tank was to be used only when the ship was fully laden or on her homeward passage) was introduced prior to the completion of Mr Gilfillan’s detailed research into the safety of the Ranger vessels, in which he would draw a different conclusion: namely that - in order to improve their operational stability following the conversion of their no 2 DB tanks for fuel oil - between 20 and 50 tons of permanent ballast should be provided onboard the Gaul’s remaining sister vessels.

Extract from transcripts of evidence Day 11 OFI - 8th October 1974

The lie

In the above extract from the OFI transcripts, it can be seen that the DOT’s counsel (Mr Brice) is asking the witness patently leading questions, suggesting to him that operational procedures would be sufficient to ensure compliance with IMCO stability standards, and also that such procedures were, perhaps, preferable to the provision of 20-50 tones of permanent ballast.

With regard to stability following the conversion of no 2 DB tank for carriage of fuel oil, the shipyard’s hand calculations [3] of 1974 can be readily replicated, and these clearly show that the IMCO stability criteria would not have been met in all of the Gaul’s normal operating conditions, regardless of any diligent skipper’s desire to ensure ‘proper distribution and use of fuel’ and the ‘proper operation of the ship’, as Mr Brice puts it.

Such calculations show that not only was the OFI proposition, that operational measures would suffice, incorrect, but it was also a lie. In carrying out their detailed analyses of the Gaul’s stability reserves, the owners, the builders and the DOT would all have been well aware of the fact that it was not possible for the vessel (as modified) to meet the IMCO minimum stability criteria for the ‘arrival in port’ condition and the seagoing conditions that preceded it.

In fact Mr Gilfillan admits this in paragraph 3 above, but Mr Brice quickly brushes over this fact by suggesting that a lack of adequate stability would only arise if the vessel were “improperly operated”.
(Note: Mr Brice’s rejoinder to Mr Gilfillan’s advice: “but not in all conditions” should have been to seek clarification regarding those conditions in which the vessel did not meet IMCO minimum stability criteria.)

Additionally, the appropriate viewpoint [4] for the DOT, in terms of trawler safety, should have been that an operational solution (which would still retain the inherent risk of human error) for a stability shortfall would always be inferior to a permanent solution that restored a ship’s stability to its desired condition.
The provision of permanent ballast onboard the Gaul’s sisters would have been a permanent solution, and one that would not have affected the vessels’ ability to catch fish or the quantity of catch (470 tons) that they could carry.

The Re-opened Formal Investigation 2004 (RFI)

During the 2004 RFI, the cover-up that had its origins in the 1974 OFI was duly consolidated, orchestrated by the DfT who were familiar with the Gaul case and the issue of her questionable stability.

Additionally, a new cover-up was put in place, one that would also conceal the obvious design faults in the duff and offal chutes on the Gaul and put the cause for her loss down to ‘crew and operator error’.

The cover-up continues to this day.

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[1] Ranger Cadmus, Ranger Calliope, Ranger Callisto and Ranger Castor (Gaul)

[2] Consensus between the DOT, the Owners and the Builders. It should be noted that all three parties had an interest in obtaining a favourable outcome from the formal investigation, as all could be open to criticism:
- The DOT, who only carried out a superficial document review prior to erroneously certifying the Gaul’s stability in 1972
- The builders, who had produced the Gaul’s stability documentation which contained errors and which over-estimated the Gaul’s stability reserves
- The Owners who had operated the vessel outwith the scope of Gaul’s official stability documentation.

[3] Manual integration of statical stability curves using Simpson’s rules. Calculations have also been carried out using modern ship stability software (with free trim capabilities and automatic free surface correction for tanks) and these show that (after correction for shipyard errors) whenever fishing was poor, the vessel would have had to leave the fishing grounds at a point when approximately 50% of their fuel had been used, to enable them to arrive back in port with more than 100 tons of fuel remaining onboard (this residual weight of fuel was necessary to enable the vessel to meet the IMCO stability criteria on the return voyage). In brief, the conversion of the number 2 Double bottom water ballast tanks for the carriage of fuel oil did not actually extend the operational range of the vessels, it merely substituted fuel oil for seawater, which still had to remain onboard the vessel as ‘ballast’ if minimum stability standards were to be met.

[4] The DOT’s unusual views regarding the provision of ballast become more explicable if we consider that, had permanent ballast been proposed for the Gaul’s sister vessels following the Formal Investigation, then this would have indicated that there had been a fundamental flaw with the Gaul’s stability. Whereas, if safety improvements were required that were of an operational nature only, then it could be argued that the effects of the fuel tank conversion had not been really significant and that the Gaul’s intact stability had been basically satisfactory and that, therefore, the DOT’s certification of the Gaul’s stability documentation in 1972 had not been incorrect.