Completed PE Summary: Stolt Petrel
A short summary of the accident and action taken:
|Vessel name:||Stolt Petrel|
|Type:||Oil product/ Chemical Tanker|
|Length overall:||96.35 metres|
|Propulsion:||Single Controllable Pitch (CPP)|
|Date & Time:||4/7/09 0621 CET|
|Location of incident:||Boudewijnsluis Lock, Antwerp|
|Incident Type:||Contact damage|
|Damage/pollution:||No pollution/ damage to stern|
Stolt Petrel was berthed port side alongside, 150m ahead of the lock gate. The propeller, controlled from the port bridge console, was turning at 130 RPM with the propeller pitch set to zero. The berthing pilot embarked and joined the master, who was alone on the bridge. Just after the mooring lines had been let go, the master heard the engine pitch change, saw that the engine pitch indicated full astern, and heard the manoeuvring alarm sound. The master attempted, without success, to regain control of the pitch from the wing and centre bridge consoles, following which the chief engineer attempted to alter the pitch from the control room. Being unable to regain control of the propeller pitch, the master then pushed the emergency stop button to shut down the main engine. As the vessel gained sternway the master ordered both anchors to be let go. The third officer, at the aft mooring deck, ran a mooring line ashore and made it fast; however the line parted. Stolt Petrel made contact with the dock gate at 3 knots, causing extensive damage to her stern and minor damage to the lock gate.
Extensive testing could not identify with certainty the reason for the propeller operating astern. However, the most likely cause was the intermittent failure of the 17 year old CPP servo unit control board. The board, which was located below the engine room bottom plates adjacent to the propeller shaft, showed evidence of some heat damage.
Stolt Tankers B.V. has replaced the CPP control board and actuator arm on board Stolt Petrel and her sister vessels, and disseminated the conclusions from its investigation into this accident to its fleet.
The Chief Inspector has recommended that Stolt Tankers B.V. should:
- Review the controllable pitch control system on board its vessels to ensure that the risks of similar system failures are identified, and the effects of their failure are mitigated.
While acknowledging the actions taken by the vessel’s managers, the Chief Inspector of Marine Accidents has written to the company, strongly advising it to:
Review the operation of main engines while alongside, particularly when operating in fixed RPM mode.
Review the bridge manning requirements when manoeuvring in port.
Ensure that all crew are aware of the risks of parting mooring lines, and the need for good communication between the master and crew at mooring stations.
Ensure that accidents are reported to MAIB in a timely manner and that potential evidence, including VDR data, is preserved.
Published: September 2009