The reporter has raised a safety concern in relation the operator's internal process used to investigate a tug engine fire.
On the morning of [date], the bulk carrier [name] was being loaded at [Location 1], [State]. In a report submitted to the Australian Maritime Safety Authority (AMSA) and the ATSB, weather at the time was reported as winds from the west-north-west 10-15 knots with squalls in excess of 25 knots. The sea state was 1.5-2.0 m with regular 3 m sets rolling in. A mooring line securing [bulk carrier] to the wharf subsequently broke requiring the use of tugs to secure the vessel prior to its scheduled departure.
The reporter states tug [name] was urgently mobilised from [Location 2], approximately 30 minutes away. The second tug assigned to assist with the departure of [bulk carrier] was unserviceable in [Location 3] and a replacement tug was dispatched from [Location 3], a journey which would take three hours to reach [Location 1]. While waiting for the second tug to arrive, [tug] was holding [bulk carrier] alongside with power settings between 75 per cent and full power. After the second tug arrived, the bulk carrier was departed with tug power settings mostly at full power and for a while, emergency full power. As the bulk carrier was clearing the berth, the crew of [tug] detected an over-boost alarm on the port main engine and reduced power to that engine. A short time later, the crew detected a port main engine low fuel pressure alarm with the subsequent inspection revealing a fire on top of the engine with fuel oil spraying.
The reporter advised the operator conducted an investigation into the incident which determined the root cause of the fire to be loose bolts attaching the fuel oil transducer to the test block. The result of this investigation was reported to AMSA. The reporter, however, is specifically concerned as to why the operator's investigation did not determine how the bolts attaching the fuel oil transducer to the test block became loose and what could be done to mitigate a reocurrence including the subsequent fuel oil spray onto the engine. The reporter states, 'In my opinion, this incident had the potential to escalate into a catastrophic event, particularly if the fire had occurred earlier during the towage operation. A thorough and well-conducted investigation, followed by an in-depth discussion post-incident, could have identified valuable opportunities for improvement and risk mitigation'.
The reporter finally states, 'I have significant concerns regarding the absence of established procedures for conducting the investigation. This includes the lack of appropriate qualifications of the appointed investigator and the exclusion of crucial witness input. Addressing these deficiencies is essential to ensure a comprehensive and credible investigation process that enhances safety and operational efficiency moving forward'.
In regards to the incident referred to in the REPCON:
Investigation process used was typically as per the overview offered.
Local preliminary report, also a Form 18 to AMSA within four hours, both are viewed by [senior management group] and the contract customer, and the Form 18 is followed by a Form 19 to AMSA within 72 hours. Closure is required when investigation is complete, within soonest timeframe or by month end, whichever is applicable. All phases are open to challenges from key stakeholders, [senior management], regulators, and customer.
More detail as follows:
Communications establish vessel and crew safety and wellbeing at the start of each, and every, conversation with the Master. In this instance promptly thereafter departure from towage, as communications were already free flowing due to [bulk carrier] predicament and weather event leading up to the incident.
Requested Form 18 (supplied to the ATSB) and internal preliminary report soonest.
Safely secured vessel to calm water cyclone mooring for assessment of incident.
Received both for assessment and filing to authorities. This required several calls to the Master to establish terms used by the crew and not known to the technical department, 'full power' versus 'emergency full power'. These are not used in greater national fleet and as such not recognised by our senior technical representatives during ongoing conversations.
Ferried Original Equipment Manufacturer (OEM) tech on board for any repairs and assessment of cause requesting a service report. The service report received for review, at a later date, the investigator then required an OEM recommended preventative measure. (Supplied to the ATSB)
Form 19 (supplied to the ATSB) was submitted within the 72-hour timeframe as required. The completed internal incident report filed into system and to customer.
The investigator utilised communications with the Master, technical department of [Operator], and OEM subject matter field technicians and system technicians.
Local investigators hold between them Dual Tap Root investigation qualification issued by Tap Root organisation. Lead has also Five Whys investigation qualification internal. Both hold International Organization for Standardization (ISO) auditor's internal qualification. Lead also holds Designated Person Ashore qualification issued by a third-party independent Registered Training Organisation (RTO).
The investigator requested a review of the investigation from the [manager] on the [date]. This was followed by another review by the investigator on [date].
The findings still stand and further issues with the systems investigated have not arisen locally or within the national fleet. Continued use of the preventative measures are in place.
Engine manufacturer methodology/OEM recommendation to prevent reoccurrence below;
'From my understanding and discussions with the local team, the issue from the original fault may have occurred due to degradation of the rubber mounting of the protection group. With the mount degrading and losing strength, this vibration has played its toll on the sensors and lines.
[Engine manufacturer] does not specifically have a recommendation for a life expectancy of these mounts, so no periodic replacement is scheduled in. On the [engine manufacturer] global network, these mounts do not have a high failure rate for that part number, so [engine manufacturer] haven’t raised it as an issue requiring rectification.
The operation and maintenance manual does have a call out for checking of the engine protection devices at 1,000 hours. Nothing specifically is mentioned in this procedure for the checking of the mounts, but as a whole, a general check for condition of the mounting would be assumed when conducting alarm and shutdown testing.
As with the current arrangement and Technical Engine Analysis (TAM) inspections being what covers off the alarm and shutdown testing, these mounts could become a replacement item that is included in the repair scope for completing TAM inspections.
Unsure what the flexibility of the TAM inspection scope is and if this could become something that is included in this procedure? Could this be something that is also included in the rounds completed by the engineers on board?
I refer to ATSB REPCON no. RM2025-0003 (the report) in relation to the [tug] engine fire investigation process, and your request for comments.
AMSA notes the concerns raised in the report regarding the effectiveness of the company’s investigation into the incident.
I confirm that AMSA was in contact with the company shortly after the incident. AMSA is aware of the actions taken by the company in response to this incident, and AMSA does not intend to take any regulatory or enforcement action in relation to this matter. AMSA also notes that the local authorities, including the Regional Harbour Master were also provided with the reports and information provided by the company at the time of the incident.
AMSA is empowered to perform a range of compliance and enforcement functions and may conduct investigations consistent with applicable marine safety and pollution prevention legislation. This does not however extend to conducting ‘no blame’ safety investigations and it remains open for the ATSB to exercise its powers investigate this matter under the Transport Safety Investigations Act 2003.
The reporter raised further queries in relation to the response provided by the operator. The operator was invited to provide an additional response to address the reporters queries below:
1. Operator investigation process.
The reporter states the qualifications named in the operator response are designed to drill down and identify a root cause to an incident. The reporter further states that an actual root cause of the tug fire was not mentioned in the operator response
Operator response:
The root cause of the fire - technical failure
Root cause description - Loose Danfos transducer
2. What are the ‘preventative measures in place’ mentioned in the operator response?
Operator response:
Conduct OEM scheduled inspections at 1,000 hour intervals of pressure sensors as per OEM recommendations.
3. The reporter queries why witness interviews were not conducted which is an element of the Tap Root investigation qualifications held by the investigators.
Operator response:
Interviews were conducted as previously stated. The investigator utilised communications with the Master, technical department of [Operator], and OEM subject matter field technicians and system technicians.