CHIRP: Crew vigilance prevents mooring incident

  • Safety Flash
  • Published on 15 August 2023
  • Generated on 9 March 2026
  • IMCA SF 20/23
  • 2 minute read

The Confidential Human Factors Incident Reporting Programme (CHIRP ) has shared an event in which the careful vigilance of vessel crew prevented a mooring incident

What happened?

The Confidential Human Factors Incident Reporting Programme (CHIRP) has shared an event in which the careful vigilance of vessel crew prevented a mooring incident.

A long, low-amplitude swell was causing a steady yawing and rolling motion of up to around 1.2 m from the wharf on a  93,000-tonne deadweight bulk carrier alongside.

During this time, a forward spring line running over the edge of the shipside roller fairlead began interacting with another mooring line causing significant abrasion damage.

What is CHIRP?

CHIRP stands for the Confidential Human Factors Incident Reporting Programme

CHIRP is a charity providing an independent, confidential incident and near-miss reporting programme to improve safety at sea for mariners worldwide.

CHIRP investigates every report and publishes anonymised findings to raise awareness of safety issues.

 IMCA works closely with the CHIRP Maritime Advisory Board.

What went right?

  • Good monitoring of the lines by the vessel crew picked up the damage.

  • There was good communication on the vessel and between the vessel and the terminal.

  • The lines were replaced and re-run by the ship’s crew before they parted.

What went wrong?

  • CHIRP observed that “the design of the roller fairleads was not optimised to prevent contact with the sheer strake. Additionally, like many vessel spring lines, they can be susceptible to abrasion when environmental conditions at the port result in excessive movement.”
A long, low-amplitude swell was causing a steady yawing  and rolling motion of up to around 1.2m from the wharf on a 93,000-tonne deadweight bulk carrier alongside.  During this time, a forward spring line running over the edge of the shipside roller fairlead began interacting with  another mooring line causing significant abrasion damage.

Lessons learnt

  • The importance of good communication and good teamwork.

  • Safety by design – CHIRP notes that many mooring fixtures and fittings are applied to the ship’s structure to meet compliance with the ship’s design requirements. Still, many are not properly designed to ensure that their directional lead is optimised to prevent abrasion of the line and maximising their resistance to the applied force on the line.

    • How well do your mooring arrangements work?

    • Do you have to use other rollers to obtain a better lead?

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