Non-fatal man overboard incident

What happened?

A member of the vessel crew fell into the sea during personnel transfer using a Crew Tender Vessel (CTV).  The incident occurred when the vessel was stood by at anchor.  The vessel was using the azimuth thruster to create lee for the CTV coming alongside.  A pilot ladder was used, rigged port side aft, around 1.5m above the waterline.

Two personnel transfers took place safely, in which fifteen persons boarded the vessel.

During the third transfer, there was a vessel black-out and the azimuth thruster stopped working.  The decision was taken to continue the transfer operation, and 8 persons safely embarked the vessel.  However, as the ninth person stepped over from the CTV to pilot ladder, the CTV rolled to port, away from the pilot ladder.  This created an imbalance for the person stepping over and he fell into the sea.  He was rescued unharmed.

What went wrong?

  • Uncontrolled and unexpected movement of the CTV;
  • Vessel could not give lee owing to azimuth thruster being unavailable;
  • The power demands of the azimuth thruster exceeded the vessel power available, causing a power outage.

What were the causes?

  • Stop Work Policy was not used;
  • Personnel transfer operations were continued when they should have been stopped – weather and sea conditions were under-estimated;
  • Human error – the blackout occurred because there was insufficient power available; the person in control of the azimuth thruster allowed the thruster load to increase too fast, causing the blackout.

What lessons were learned?

  • Better management of vessel electrical systems – having more generators online – could have averted this incident;
  • Decision making in marginal conditions: the decision to have the transfer at all in marginal sea conditions, and the decision to continue the transfer once the vessel was unable to provide lee, were contributory factors.

What action was taken?  

  • Company action to install/purchase boat landing platform instead of pilot ladder.