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MCIB report into the sinking of the FV “Aztec” off Duncannon Harbour on 11 January 2021
The Marine Casualty Investigation Board report into the sinking of the FV “Aztec” off Duncannon Harbour, Co Wexford on 11 January 2021 has found the fishing vessel sank as a result of having a hole in the aft deck which allowed seawater to flood the steering compartment.
At 07.00 hours on the 11 January 2021, the “Aztec” departed Duncannon Harbour, Co. Wexford with four persons onboard, to pair trawl with the “FV Western Dawn” for sprat.
At 09.30 hrs they hauled the net, took sprat onboard, and stored them below deck in secure pounds. At approximately 10.00 hrs the “Western Dawn” shot its net, and the “Aztec” took onboard the end for the next tow. As it prepared to take the ends, the fishing weight of approximately 350 kilogrammes (kg) fell from the gunwale onto the deck.
At 10.45 hrs the “Western Dawn” hauled its net and the “Aztec” passed back the end of the net to the “Western Dawn”. The “Western Dawn” then commenced passing fish over to the “Aztec” and during this operation a crew member noticed a hole in the starboard aft section of the deck allowing water to flood into the steering compartment. As the stern settled deeper in the water the skipper manoeuvred the “Aztec” alongside the “Western Dawn” and instructed the crew to transfer.
The 11.89 metre “Aztec” then sank within a minute, 500 metres south of Duncannon Fort, Duncannon, Co Wexford.
The “Aztec” was built in 2005 by Seaways in Macduff, Scotland and was a Glass Reinforced Plastic (GRP) hull with aluminium wheelhouse and wooden decks. The “Aztec” had been laid out for stern trawling. It is arranged with a forward lantern style wheelhouse set over a raised flush foredeck. Below deck, the vessel had watertight bulkheads end of the engine room. The bulkhead between the fish hold and the steering compartment has 25 millimetres (mm) drain hole fitted so cannot be considered a watertight bulkhead. The drain hole allows water drain from steering compartment into the fish hold. The fish hold hatch is just aft of midships. The transom fitted goal post type gantry fitted is with net drums. The main engine consisted of a Caterpillar 3406 which developed 150kW power for propulsion, hydraulic and electrical power.
The first trawl of the day was recovered at 09.30 hrs and stowed in the fish hold. It is estimated that at least eight tonnes of sprat were caught at this time causing significant loading on the vessel. The load condition stability calculations carried out in 2017 allowed for ten tonnes of loose fish in pounds in the fish hold. This will have been calculated as evenly spread whereas on the day of the incident the previous catch was loaded into the after end of the fish hold first which will have trimmed the vessel by the stern causing the after end to sink deeper into the water.
As the “Western Dawn” shot its net for the “Aztec” to take the end for the next tow the towing weight for the net dropped from the gunwale of the “FV Aztec” onto the starboard aft deck. This action punched a hole through the deck of approximately 300 cm2. This went unnoticed by the crew at this time due to the amount of gear located around this area of the deck.
After the “Western Dawn” recovered its net and took onboard part of the catch, it handed over the net to the “Aztec” to recover the remainder of the fish. During the operation to recover these fish, the net was hauled close to the starboard after end of the “FV Aztec”. The cod-end was then attached and lifted using the derrick. The height of side derrick for cod-end lift above deck level is 5.06 m and the distance from side derrick block head to centreline of vessel is 2.54 m. The height of aft towing block above deck level is 1.6 m.
In its report the Marine Casualty Investigation Board (MCIB) notes that these actions combined caused the after deck on the starboard side to dip into the water. This action resulted in the steering compartment starting to flood through the hole in the deck.
The skipper noticed that the water was not clearing the aft deck in the usual manner, and the same time a crew member noticed that water was flooding into the steering compartment through a hole in the deck. The crew member attempted to stem the flow with an oilskin and alerted his skipper.
The lack of a bilge alarm in the steering compartment meant this was not picked up until it was noticed by one of the crew. Despite attempts by the crewmember to stem the flow, the steering compartment continued to flood resulting in loss of buoyancy in the after end of the vessel. The steering compartment consisted of a free area of approximately five cubic meters and provided the majority of the buoyancy to the after end of the vessel. This caused the vessel to settle further by the stern ultimately leading to flooding of the fish hold through deck scuppers and open hatch.
In their conclusions, the MCIB found that, “The vessel was heavily laden at the time and dependant on the buoyancy provided by the steering compartment to maintain its longitudinal stability. Although not required, the “FV Aztec” had stability calculations done in 2017 for a condition with ten tonnes of fish in the hold. These stability calculations concentrated on lateral stability and did not address longitudinal aspects of stability. It was stated during recovery operations that the “FV Aztec” had between ten and 12 tonnes of fish onboard. Although no limits are set for vessels of this size, the loading of the vessel was a contributory factor in the sinking. This must take into account the weight of the catch onboard as well as the positioning of fish in the hold. The effect of the additional catch being taken onboard at the time of the incident will have also caused considerable settling by the stern and listing to starboard. The combination of these forces will have left the longitudinal stability of the vessel dependant on the buoyancy provided by the steering compartment.”
SAFETY RECOMMENDATIONS
- The Minister for Transport should issue a Marine Notice to owners/skippers of fishing vessels reminding them to be aware of the safe loading capacity of their vessels. Also, to be aware where the stability in a loaded state is dependent on a compartment’s watertight integrity it is advisable that compartment is alarmed and has a means of being pumped out.
- The Minister for Transport should issue a Marine Notice to owners/skippers of fishing vessels reminding them that where an area of deck is subjected to regular working and shock loading, consideration should be given to re-enforcing and strengthening that area.
- The Minister for Transport should review the Code of Practice for Fishing Vessels under 15 meters to take into account heave loadings on decks during fishing operations.
- The Minister for Transport should review the Code of Practice for Fishing Vessels under 15 meters to take into account the maximum load of bulk fish a vessel is authorised to carry.
Read the full report by clicking here.
