The Report on the investigation into two catastrophic engine failures, one resulting in a fire, on board Wight Sky at the entrance to Lymington River and before berthing at Lymington Pier on 26 August and 14 December 2018 was recently published.
On 26 August 2018, Wight Sky suffered a catastrophic main engine failure as she prepared to enter the Lymington River on its regular crossing from Yarmouth, Isle of Wight.
This was the ferry’s second catastrophic main engine failure in less than a year, the failed engine being the replacement for the previous failure that had resulted in a fire and serious injuries to an engineer officer.
On 14 December 2018, Wight Sky suffered a third catastrophic engine failure. On this occasion, the failed engine was a new build and had been in operation for just 389 hours.
Wight Sky was one of three Wight Class sister ferries and following the third engine failure Wightlink withdrew its Wight Class ferries from service.
Following discussions between the ferry owner, the Maritime and Coastguard Agency, Lloyd’s Register, and the engine manufacturer Volvo Penta, a mitigation plan was put in place to enable the ferries to return to service.
This investigation found a history of engine failures across the Wight Class fleet dating back to 2010 and consequently, the scope of the investigation expanded to include all known failures.
This led to a long and detailed technical investigation that comprised forensic examination and testing of five of the failed engines and their components, a full review of the vessels’ system design and operation, and the safety management, planned maintenance and condition monitoring procedures, together with manning and technical oversight.
In May 2019, the MAIB published an interim report of its initial findings.
The key safety issues identified were:
Insufficient technical oversight of the engines’ operating parameters.
Standards of maintenance management and quality control.
Engine component and auxiliary system design problems.
A lack of clear ownership for engine maintenance and engine condition monitoring.
Wightlink: Ensure competent technical oversight of maintenance on board its vessels, through resourced procedures, so that technical issues are identified and escalated to senior management as necessary.
Volvo Penta AB: Identify all affected D16 MH customers to inform and resolve the identified oil filter bypass anomaly.
Lloyds Register: Assess the need to introduce within its rules and regulations the time taken to declutch a main propulsion engine from the drive shaft in the event of an emergency shutdown, to prevent the engine from being driven and increasing the risk of serious injury and damage.
RK Marine Ltd: Provide its customers with all manufacturers’ safety bulletins applicable to the engines in use.
Andrew Moll, Chief Inspector of Marine Accidents, said: “This has been a long and complex investigation. Initially focussing on two catastrophic engine failures, the investigation found a history of engine failures across Wightlink’s fleet of Wight Class ferries dating back to 2010.
“Consequently, the scope of the investigation was broadened to include the forensic examination and testing of five failed engines and their components, a full review of the vessels’ propulsion system design and operation.
“We also examined the ferry operator’s safety management, planned maintenance and condition monitoring procedures, together with the technical oversight provided by the engine manufacturer and its approved service provider.
“MAIB has worked closely with Wightlink, Volvo Penta AB, Lloyds Register and the Maritime and Coastguard Agency over the past three years to help ensure that most of the technical issues identified in the investigation report were addressed as soon as practicable.
“The report contains recommendations aimed at improving the reliability of the propulsion machinery on board the Wight Class ferries and reduce the likelihood of future catastrophic engine failures.”