The National Transportation Safety Board (NTSB) has released an investigation report on the towing vessel Capt. Kirby Dupuis, which experienced an engine fire on November 9, 2021.
On November 4, 2021, at 0600, the Capt. Kirby Dupuis departed Paducah, Kentucky (near mile 950), bound upriver for Steubenville, Ohio (near mile 68), pushing thirteen dry cargo barges filled with sand, rock, and steel. The vessel had a crew of six: the captain, pilot, a “deckineer”, and three deckhands. The deckineer was completing a company training program to be qualified as an engineer.
On the morning of November 9, the towboat was transiting with both engines about 1,275-1,290 rpm for a speed of about 5– 6 knots. About 0708, the captain, on watch in the wheelhouse, noticed a flash on the engine room video display. Immediately following the flash, the vessel’s fire detection system alarmed. The captain sounded the general alarm and instructed the deckhand on watch to notify all crewmembers about the fire and to begin firefighting efforts.
About the same time, the deckineer, in the engineer’s office on the main deck overlooking the engine room, saw a fire near the port main engine in the lower engine room. He retrieved a fire extinguisher and attempted to enter the upper engine room from the main deck passageway, but the smoke and heat prevented him from accessing the space. He then joined the other crewmembers to try to fight the fire from the starboard-side exterior main deck. The deckineer tried to start the fire pump from a remote pushbutton on the exterior bulkhead, but it was inoperable. Unable to enter the engine room and without an operable fire pump, the deckineer contacted the captain via handheld radio and requested permission to activate the fixed fire-extinguishing system for the engine room.
To prepare for the release, the deckineer and crewmembers closed the engine room doors, windows, and ventilation dampers on the stacks. The deckineer activated the remote emergency fuel shut offs for the engines. After securing the engine room, the deckineer returned to the main passageway by his stateroom and “hit the first fire suppression system” by pulling one of the two remote pull levers.
He observed the portside fire diminishing but then saw flames growing on the starboard side of the engine room near a stack of boxes filled with oil filters. He told investigators that he believed the fire had traveled across the engine room from the port main engine to these boxes because the port ventilation supply fan, which discharged directly above the port main engine, remained on during the initial stages of the fire.
The deckineer and a deckhand discharged about eight portable fire extinguishers through a slightly opened engine room door on the main deck. However, the fire continued to grow, and black smoke hindered their ability to fight the fire. When they saw that the fire had started back up on the port side of the engine room, the deckineer informed the captain that he needed to “hit the second fire suppression system” and the deckineer pulled the second remote lever. The fixed fire-extinguishing system was fitted with sirens to audibly alert personnel that the product was about to discharge. However, the deckineer, located outside the space, stated that he did not hear any sirens nor product discharging into the engine room from the system nozzles in the engine room upon activation. He told investigators he believed the fixed fire-extinguishing system extinguished the fire and stated, “the fire was pretty much out before the fire department got there.”
Meanwhile, the captain and pilot had contacted the US Coast Guard, the operating company, and nearby vessels. The Capt. Kirby Dupuis had lost propulsion and electrical power, but the tow remained intact and drifted into the right descending bank.
The fire caused extensive heat and smoke damage to the vessel’s engine room. The upper and lower engine room bulkheads and overheads were completely burned by the fire as well as the machinery, fixtures, and equipment in the upper engine room. A marine surveyor estimated the damages to be 1.8 million dollars.
The engine room video showed that, within 10 seconds of the leak starting, the oil sprayed inboard into the center of the engine room and upward onto the exhaust manifold on top of the running engine. Immediately after contacting the hot surface of the exhaust manifold, the oil ignited and started the fire. Forced air from the running ventilation supply fan discharging above the engine fueled the fire with oxygen and propelled it across the engine room, damaging the starboard engine and the equipment in the upper engine room.
Although the crew attempted to activate the vessel’s fixed fire-extinguishing system – and believed they had successfully discharged the fire suppression fluid – investigators determined that the system was not activated during the fire. After the fire, the nitrogen pilot cylinder lever was found in the “set” position and its cylinder was still fully charged. Both suppression fluid cylinders were also found full to capacity after the fire. Despite the deckineer stating that he pulled both remote pull levers, only the “valve release” lever was found to be fully extended; its attached cable properly opened the globe valve.
Although the crew drilled regularly in the months preceding the fire, including simulated fires in that included the upper engine room, they did not include scenarios or exercises that simulated activation and operation of the fixed fire-extinguishing system. The deckineer referred to the system as having a “first” and “second” bank, and his actions during system activation were consistent in attempting to use a primary dispersion of suppression fluid, followed by a secondary release of additional fluid— contrary to the system’s design for a single pressurized release.
The NTSB determined that the probable cause of the engine room fire aboard the towing vessel Capt. Kirby Dupuis was a lube oil tube on the port main engine that vibrated out of a joint due to a missing retaining ring and mounting bracket, spraying pressurized oil that made contact with a hot exhaust surface and ignited.
Contributing to the severity of the fire damage was the crew’s unfamiliarity with activation procedures for the fixed fire-extinguishing system, which resulted in an unsuccessful attempt to release the fire suppression fluid and extinguish the fire.
Lessons learned
The small confines of the engine room space and the location of fire equipment within that same space demonstrate a risk to crews fighting engine room fires. On towing vessels, the risk to crews fighting engine room fires has led to the development of designs that incorporate both a means for securing ventilation to the engine room and a fire-extinguishing system to extinguish the fire without requiring crews to enter the space. Crewmembers should train for engine room fires and review extinguishing system instructions. Training drills should ensure that crewmembers are familiar with fixed fire-extinguishing systems and procedures, including confirming crew evacuation, isolating the protected space, and activating the system.
Download the report: NTSB Engine Room Fire Capt Kirby Dupuis 2022
