The interim report released by Accident Investigation Board Norway elaborates about the black-out and loss of propulsion of the cruise vessel Viking Sky.
Summary of the incident
On the afternoon of 23 March 2019, the cruise vessel Viking Sky experienced a black-out
and loss of propulsion in gale to storm force conditions in the Hustadvika area of the
Norwegian Coast. The master immediately sent out a mayday as the ship drifted towards
shore.
Viking Sky was manned by 458 crew and was carrying 915 passengers. Most of the
passengers were US (602) and UK (197) citizens, followed by Australians (69) and other
nations (47).
On the morning of 23 March, between 0500 and 0904, 18 lubricating oil low level and
low volume alarms were registered by the operational DGs. Each alarm, having been
accepted, cleared within a few seconds.
No more alarms were registered until 13:37:04 when DG4 registered an alarm indicating
that the DG was shedding load as a result of low lubricating oil pressure. A few seconds
later it registered a low lubricating oil pressure alarm. At 13:39:52, DG1 registered a low
low lubricating oil sump level alarm. A little over five minutes later, at 13:45:26, DG4
shut down followed by DG2 eight seconds later. DG2 was restarted after approximately
11 minutes, but shut down again along with DG1 at 13:58:31, causing a complete blackout and loss of propulsion.
The bridge team immediately called the engine control room but, at that early stage, the
engineers were unsure of the cause, or causes, of the blackout and therefore could not
estimate when it would be possible to restore power. The officer on watch called the
master, who quickly made his way to the bridge.
Having assessed the situation, the master broadcast a mayday at 1400. He then instructed
the crew to drop both anchors. However, the anchors did not hold, and the ship continued
to drift astern towards the shore at a speed of 6–7 knots. The General Alarm was
activated at 1413 and the passengers and crew began to muster.
On receipt of the mayday, Southern Norway Joint Rescue Coordination Centre (JRCC)
launched a major rescue operation and started scrambling resources, including
helicopters, on a large scale.
Initial findings
- The lubricating oil sump tanks of all the diesel generators were maintained at 28%–
40% capacity. - MAN’s recommendation was to maintain them at 68%–75% capacity.
- The diesel generators shut down as a result of the loss of lubricating oil suction due to
low sump tank levels, combined with pitching and rolling. - All three operational diesel generators shut down within 19 minutes of each other,
causing blackout and loss of propulsion. - AIBN estimate that Viking Sky came within a ship’s length of grounding, having
passed over or in immediate proximity to 10 m shoals, before propulsion could be reestablished.
Actions taken
- Shortly after the incident Wilhelmsen Ship Management distributed a Safety Bulletin
including recommendations to all their vessels. - The company has also identified several actions to be taken following their internal
investigation of this incident. - Specifically, they are reviewing the management of appropriate lubricating oil levels in operational machinery, the preparations for heavy weather and the instructions regarding blackout recovery.
- Additionally, in cooperation with Class, they are establishing procedures for sailing with one engine (or other critical equipment) inoperative while maintaining compliance with the Safe Return to Port3 requirements.
On 27 March 2019 the Norwegian Maritime Authority issued a Safety Message on risk
assessment of critical systems which asked “all shipping companies to take the necessary
precautions to ensure the supply of lubricating oil to engines and other critical systems
under expected weather conditions. This should be done in collaboration with the engine
supplier and included as part of the ship’s risk assessments in the safety management
system.”
Recommendations
The safety advice issued by the Norwegian Maritime Authority is supported by the
ongoing safety investigation, with the following recommendation.
All vessel owners and operators are recommended to ensure that engine lubricating oil
tank levels are maintained in accordance with engine manufacturer’s instructions and
topped up in the event of poor weather being forecast.
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Source: AccidentInvestigationBoardNorway
