At about 0230 on 22 July 1998 a fire broke out in the engine room of the Antarctic research and supply vessel Aurora Australis.The ship was about 1300 miles south of Tasmania with 54 special purpose personnel (or expeditioners), 24 crew and an ice pilot on board.
About 25 minutes before the outbreak of the fire, the duty engineer had been woken by an alarm on the unmanned machinery space monitoring panel in his cabin. He went to the machinery control room and inspected the engine room. He cancelled the alarm and returned to his cabin at 0213. At that time, everything in the engine room appeared to be normal.
The duty engineer was roused again at 0225 by another alarm and, returning to the engine room, he discovered a fire at the forward end of the port main engine, around the turbocharger. The engine was stopped and the fire alarms sounded.
The fire at the turbochargers was attacked by engineers using portable extinguishers and apparently extinguished. A few moments later, however, at about 0236, a fireball erupted and the engineers were forced to evacuate the engine room. The expeditioners and crew were mustered on the helicopter deck and the fire teams deployed. Preparations were made for the operation of the fixed fire fighting system protecting the engine room.
The Halon 1301 fixed smothering system was released at 0252.Following the release of the halon gas, a MAYDAY message was transmitted and communications were established through Sydney Maritime Communications Centre.
From 0340 onwards, the engine room was re-entered on a number of occasions using self-contained breathing apparatus.
After consultation with the Tasmanian Fire Service by facsimile, ventilation of the engine room commenced at 1444. At about 1540 the engine room could be entered without breathing apparatus for a full inspection.
Although there was some damage to the port engine and turbochargers, the critical damage was to the electrical wiring of power and control circuits carried in cable trays affected by the fire. There was also some water damage, the result of water freezing in pipes in the Antarctic conditions.
Over the next three days, the ship's crew carried out repairs and 'jury rigged' electrical wiring to restore propulsive power to the starboard engine and electrical power to ancillary equipment.
Aurora Australis arrived back in Hobart on 31 July 1998, under its own power.
Investigation of the fire scene showed that the fuel source was from a split flexible hose between the port engine fuel filters and a length of rigid pipe on the fuel spill line.
It was also found that out of ten halon gas bottles, four had failed to discharge.
These conclusions identify the different factors contributing to the incident and should not be read as apportioning blame or liability to any particular organisation or individual. Based on all the evidence available, the following factors are considered to have contributed to the fire:
- The fire was caused by diesel fuel from a split in the flexible fuel hose in the spill line from the main engine coming into contact with a component of the port engine turbo-chargers, the temperature of which was in excess of the auto-ignition temperature of the fuel.
- Failure of the hose was due to its age and to 'wear and tear'.
- Although recommendations relating to fixed pipework on the engines, contained in the Wrtsil Technical Bulletin 'Safety aspects on and maintenance of fuel supply system of VASA 32' issued three years earlier, were implemented by the company, the recommendations in the same bulletin relating to the fitting, care and maintenance of sheathed hoses in the low pressure fuel system, were not followed.
- When fitting the flexible fuel hoses at some time between 1991 and 1992, the ship's drawings were not altered to show the modification to the system.
- Consultations between the company and Lloyd's Register, and the company and Wrtsil, on the use of flexible hoses were 'ad hoc' and no record of consultation or approval concerning their fitting was made by any party.
- No approval was sought from the Australian Maritime Safety Authority for the fitting of flexible hoses.
- Knowledge that the flexible hoses had been fitted under the floor plates was lost with the turn-over of engineers.
- The fact that other flexible hoses were fitted to the engines was well evident, but this did not alert either class or AMSA surveyors to the fact that the modifications were not approved.
It is also considered that:
- In general the response to the fire by the ship's crew and the expeditioners on board was measured, effective, demonstrated initiative and reflects great credit to all on board. Entry into any area adjacent to a fire, however, alone and without breathing apparatus or backup, is extremely hazardous and could compromise an entire firefighting effort.
- The poor design of the electrical operating system for the Halon 1301 fixed smothering system led to its unreliable operation and to the partial discharge, only, of the halon.
- The maintenance of the halon system involved at least three contractors and ship's staff, leading to a lack of continuity in maintenance and probably to the fitting of inappropriate fuses in the 24 volt supplies to the main control units.
- Those involved in restoring propulsion to the ship showed considerable ingenuity, skill and initiative.
|Date:||22 July 1998||Investigation status:||Completed|
|Release date:||28 June 1999|
|Report status:||Final||Occurrence category:||Incident|
|Highest injury level:||None|
|Type of operation||Research and Antarctic supply vessel (Ice Class)|
|Damage to vessel||Substantial|
|Departure point||Hobart, Tasmania|