The National Transportation Safety Board (NTSB) has published an investigation report into an incident where a fishing vessel suffered an engine room fire while transiting the Pacific Ocean resulting in its sinking.
The incident
On September 10, 2024, about 1600 local time, the commercial fishing vessel Tarka II was transiting in the Pacific Ocean about 4 miles southwest of Tatoosh Island, Washington, when the captain discovered a fire in the engine room. The two crewmembers on board did not attempt to fight the fire. They abandoned the Tarka II into a liferaft and were rescued by the US Coast Guard. The fishing vessel later sank with an estimated 1,000 gallons of diesel fuel on board. There were no injuries. The vessel was not recovered and considered a total loss, valued at $460,000.
Analysis
While the fishing vessel Tarka II was transiting in the Pacific Ocean, a fire began in he engine room. The two crewmembers on board abandoned the vessel into a liferaft and were rescued by the Coast Guard before the vessel eventually sank. The captain observed smoke emanating from the sides of the exhaust stacks located just aft of the wheelhouse (likely from engine room vents on or near the main exhaust stacks). When he entered the engine room, he noticed white smoke that smelled like engine exhaust, and he believed there was an exhaust leak.
After shutting down the generator and main engine, the captain then noticed a small, smoldering fire on the port side of the engine room near the hydraulic tank and hydraulic pump. Shortly after the captain observed the fire, the smoke turned black, and the flames intensified. The rapid growth of the fire and black smoke indicated a fuel source ignited, and opening of the engine room door introduced additional oxygen to the fire, further intensifying the fire.
The hydraulic lines for the davit were not pressurized at the time of the fire. However, the steering system’s hydraulic lines (pipes and hoses) were pressurized. The captain noted that hydraulic lines ran “inches” from the engine exhaust pipes, which were protected by fiberglass lagging. Investigators were unable to verify the condition or arrangement of the exhaust lagging in the engine room because the vessel sank and there were no photos available of the engine room before the fire.
The captain reported that the smoke initially looked and smelled like engine exhaust. It is possible that exhaust pipe heat, or an exhaust leak, either from the main engine or the running no. 1 auxiliary generator, ruptured one of the pressurized hydraulic lines, causing the hydraulic fluid to spray and ignite on a nearby, unprotected hot surface, and spread to nearby combustibles. However, because the Tarka II sank and was not recovered, the exact source of the fire could not be determined.
The captain had no indication of the fire before he saw smoke coming from the sides of the vessel’s exhaust stacks. The Tarka II engine room was equipped with a CCTV camera that displayed on a monitor in the wheelhouse, but it was not in use at the time of the fire. Additionally, there were no smoke or fire detectors installed in the engine room, nor were any required.
The two smoke detectors on board were located just outside of the engine room door and in the galley, and they only activated after the captain opened the engine room door to investigate the smoke. It is unknown how long the fire had been burning before the captain noticed smoke; however, had the engine room CCTV system been on or had smoke or fire detectors been installed in the engine room, the captain would have likely been alerted to the fire sooner.
Conclusions
Probable Cause
The National Transportation Safety Board determines that the probable cause of the fire aboard the fishing vessel Tarka II was an unknown source within the engine room.
Lessons learned
Effective placement of smoke and fire detectors
Installation of smoke and fire detectors in spaces that are typically uncrewed when underway, such as the engine room, allows for the earliest detection and notification of a fire, maximizing the time for operators to respond to the fire or take actions to abandon the vessel. Vessel operators can improve fire safety by installing detectors in all areas susceptible to fire (such as the engine room and galley, and spaces that contain machinery, hot exhaust tubing, and fuel sources). Additionally, the detectors should be capable of notifying crewmembers throughout the vessel of fire or smoke and be routinely checked to ensure they are in good working order.
