PC: Marine Accident Investigation Branch
The skipper had been awake from about 0600 to 0300 on the day before the accident, a period of over 21 hours, and had slept for approximately 4 hours immediately before taking the morning, afternoon and evening watches. The report states that the skipper had accumulated 7.8 hours of sleep debt over the four days of the fishing run, in addition to 10.25 hours carried over from the previous run, giving a chronic sleep debt of 18 hours. It adds that the 2-day rest period between runs was shorter than the usual 4 days.
Because of fatigue from working overnight to repair the pump and a build-up of sleep debt, and that the warm, comfortable and dark wheelhouse increased the risk, the skipper fell asleep.
On the evening of 16 November 2023, the prawn trawler Sustain ran aground on rocks at the entrance to Loch Broom, north-west Scotland, while returning to Ullapool. The vessel had left port in the early hours of that morning to begin day 4 of its fishing run. The grounding happened at 1946. All the crew were unharmed, but Sustain was later declared a constructive total loss and dismantled by specialist divers in early 2024. The vessel’s safety risk assessment, last reviewed on 21 June 2023, identified the risk of ineffective watchkeeping leading to grounding, according to the MAIB. The report records that Marine Guidance Note 313 (F) recommended a watch alarm on all vessels where only one person might be keeping a navigational watch. The MAIB also cites MGN 137 (M+F), which strongly advised against the watchkeeper acting as sole lookout at night. A previous accident, the grounding of the fishing vessel Golden Promise on Stroma on 7 September 2011, involved a skipper who fell asleep, and the watch alarm was probably not functioning at the time, according to the report.
The skipper, who was alone in the wheelhouse, had fallen asleep, and no watch alarm was fitted on board, according to the Marine Accident Investigation Branch report. PC: Marine Accident Investigation Branch Sustain’s wheelhouse had a plotter that fulfilled basic navigation functions but did not meet the Mini Electronic Chart Display and Information System (Mini-ECDIS) standard and had no navigational warning or alarm functionality. The report adds that there was no watch alarm fitted, and that the engine exhaust ran through the wheelhouse, making it warm in all weather conditions. Its control measures were calling another crew member if tired and ensuring a watch alarm was fitted and working correctly. The report states that these control measures were not implemented. A footnote in the report explains that watch alarms detect inactivity in the wheelhouse and sound an audible alert both locally and at other locations on the vessel. The MAIB states that the two deckhands were sorting the catch when Sustain grounded.
