The incident

Crew members on Ruby-T were testing the rescue boat crane’s limit switches, in preparation for a vetting inspection.

To reset the system, the bosun used the hand crank to wind down the wire and disengage the limit switch.

Once he saw that the wire was lowering manually, he turned around and focused on the crane control box to resume lowering under power.

As soon as he engaged the crane control box, the hand crank, which was still mounted on the crane, rotated in a fast motion and hit the bosun directly on his back.

This resulted in his chest being slammed against the crane control box. As a result, the bosun had suffered from three fractured ribs.

 

Immediate cause of the accident

At the time of the accident, the bosun was standing in a relatively restricted space of the crane’s platform, facing the control box. The switch disabling valve was closed and the hand crank was left mounted in the squared spindle. As soon as the bosun induced the R/B winch, the hand crank rotated and hit the bosun on his back.

The limit switch of the R/B winch was disengaged, allowing the winch to rotate even though the shield was lifted, due to the hand crank being inserted in the squared spindle.

 

Conclusions

  1. The bosun was struck by the hand crank as soon as he engaged the R/B winch;
  2. The switch disabling valve was shut, to by-pass the limit switches and to enable resetting of the same;
  3. Joystick (B) was damaged and, in lieu, an adjustable wrench was used, which enabled the crew to by-pass the physical barrier present on the control box;
  4. It is likely that the bosun was distracted from understanding the actual risks of his own actions, as he was most probably concerned about the damages to the wire;
  5. No symbolic barriers were present in the vicinity of the crane;
  6. The crew members were most probably unaware of the damage which could have been caused to the braking system of the crane, by cranking it in the opposite direction;
  7. No elaborate guidance for testing of limit switches was available on board.

 

Actions taken

During the course of the safety investigation, the company had taken the following safety actions:

  • A more in-depth familiarization of personnel with the crane, was carried out;
  • The investigation report was shared within their fleet to raise awareness.

 

Recommendations

Transal Denizcilik Ticaret A.S. is recommended to:

  • Develop detailed written procedures for the testing of the crane’s limit switches;
  • Put in place a distinctive arrow marking to indicate the correct direction of rotation of the crank handle.

 

Explore more herebelow:

Ruby-T report