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.