MAIB: Sinking of tug Biter with loss of two lives

  • Safety Flash
  • Published on 24 March 2026
  • Generated on 31 March 2026
  • IMCA SF 06:26
  • 2 minute read

The UK Marine Accident Investigation Branch (MAIB) has published Accident Investigation 17/2024 relating to the girting and capsize of tug Biter with the loss of two lives.

What happened?

On 24 February 2023, the twin screw conventional tug Biter girted and capsized off Greenock, Scotland while attached to the stern of the passenger vessel Hebridean Princess, which was making its approach to James Watt Dock. Biter’s two crew were unable to escape from the capsized vessel and lost their lives.

What went wrong?

  • The marine pilot’s training had not prepared them to work with conventional tugs.
  • Master/pilot and pilot/tug exchanges were incomplete and, with no shared understanding of the plan, the passenger vessel’s master and the tug masters were unable to challenge the pilot’s intentions.
  • The passenger vessel’s speed placed significant load on the tug’s lines and almost certainly caused the gob rope to render.
  • The tug’s gob rope did not prevent it being girted.
  • The tug’s rapid capsize meant the crew had insufficient time to release its towlines.
  • An open hatch compromised the tug’s watertight integrity and limited the crew’s chance of survival.

MAIB have published a full and detailed report. 

Lessons to learn

  • MAIB have made recommendations to the owners and to the port involved, including:
    • Review safety management systems and risk assessments to provide clear guidance on:
      • the rigging of the gob rope.
      • the safe speed to conduct key manoeuvres.
    • Adopt a recognised training scheme for tug masters.
    • Commission an independent review of marine pilot training.

Members may wish to refer to:

·       MAIB Safety Bulletin 1/2026

·       Video accompanying MAIB Safety Bulletin 1/2026  

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