Real Life Accident: Weakened Wire Leaves Ladder Hanging
When the vessel left port the accommodation ladder was left un-stowed in the horizontal position, hanging from the hoist wire, while crew were busy with departure tasks. Once away from berth, deck crew started the procedures for stowing the accommodation ladder in its seagoing position. Suddenly the hoist wire broke, letting the shore-end of the ladder fall. The ladder was now only attached to the ship by the main ramp. The vessel’s speed was reduced and the cargo crane was used to retrieve the ladder and place it on deck.
The wire was found to be in generally good condition and had been recently greased. Records and related photos indicate that inspection and maintenance intervals had been followed. The wire was almost two years old and was without indications of rust or defects along almost all of its length.
However, it was observed that the point where the wire broke had more rust and less grease than elsewhere. After further investigation using the wire layout it was found that the break occurred at a point where access is difficult, thus rendering maintenance and greasing more arduous and less efficient. The wire at this particular point is continually exposed to sea/weather conditions yet can be less well maintained than the rest of the wire. Additionally, when the ladder is about to be stowed or deployed these same wire parts experience the maximum amount of tension.
- The wire was already wasted at the roller positions, which are always exposed to sea and weather. Given their location, these two points are hard to access for verification and maintenance.
- The ladder’s limit switch may have been bypassed during the operation.
- All vessels’ accommodation and pilot ladders should be checked for vulnerable points and wastage.
- Instructions should be given to vessels on how to treat the wires on these accommodation ladders.
- Crew should be given instructions on the use of limit switches and how they help protect the wire from excessive tension.
- The accommodation ladder manufacturer should be informed of the weak design.