An act of crew-forgetfulness led to a gas tanker losing power for several minutes in the Port of Brisbane in March this year, the Australian Transport Safety Bureau has found.
Crew aboard the gas carrier Gaschem Homer forgot to switch two of the three ship’s generators to automatic mode. The ship’s power management system was unable to automatically distribute electrical load across all the generators.
Increased power demand by the operation of the bow thruster during departure manoeuvers could not be supported by the single generator which tripped on overload, causing the blackout.
The ATSB found that procedures were generic and non-informative, and there were no other controls in place to prevent such operational lapses resulting in power failure.
Hartmann Gas Carriers has carried out a subsequent risk assessment associated with its power management systems and has established additional controls.
Shipboard safety management systems have been amended to include guidelines for blackout prevention and procedures requiring generators to be set for automatic load sharing before manoeuvring. Pre-departure and arrival checklists for the engine room and bridge were amended to include verification of generator mode status. Targeted training for watchkeeping engineers has also be introduced, along with enhanced bridge and engine room information exchange protocols.
“This incident highlights the importance of ensuring all risks associated with shipboard operations and critical equipment are identified, assessed and effectively controlled. The safety management system should encompass up-to-date and useable ship-specific procedures, as well as any additional technical controls if procedural barriers alone are insufficient to mitigate risk,” the ATSB said.