Increase in blackouts a worrying trend
A number of near misses involving blackouts have recently been reported. Each one has been related to the incorrect use of shaft generators and has demonstrated an incomplete understanding of the use of onboard power management systems.
The MAIB accident investigation report, published in March 2012, about the grounding of the feeder container ship ‘Clonlee’, which suffered an electrical blackout while entering the Port of Tyne, UK in March 2011, stated that the probable cause was an intermittent electrical fault within the electrical power supply and distribution system. The ship lost power at the breakwater entrance when the shaft generator was being transferred to the two diesel generators. The engineers were unable to restart the power systems.
In addition to comments about inadequate bridge team composition, voyage planning and operational management by the company, the report concluded:
· “A lack of equipment manufacturers’ technical manuals on board ‘Clonlee’ compromised the engineers’ ability to competently operate and maintain the ship’s critical systems.”
· “Clonlee’s switchboard was not operated in accordance with the equipment manufacturer’s instructions.”
· “When the ship blacked out, the master became cognitively overloaded and lost situational awareness because the bridge team was under resourced.”
· “Neither Clonlee nor her crew were adequately prepared for entering the port, and the crew were not ready to respond to the machinery failure.”
Other reported near misses in 2012 , on vessels operated by reputable owners, also involved the use of shaft generators, including:
· A vessel that blacked out only three ship’s lengths from land when transferring load from the shaft generator to auxiliary generators in preparation for arrival in port
· a vessel that was using a shaft generator in combination with one auxiliary generator during port manoeuvres and did not have the other auxiliary generator on standby. The auxiliary generator failed and the full load was placed on the shaft generator, resulting in a blackout within the port itself
· an incident that occurred in confined waters where attempts were made to connect the shaft generator to the main switchboard. The load could not be synchronised and power to the cooling pumps and lube oil pumps was lost, resulting in complete engine failure. The Chief Engineer did not advise the bridge that this transfer was being attempted. The vessel narrowly avoided grounding.
In all cases, the operators were required to change their procedures to ensure that clear guidelines are provided to the crew, particularly in respect of when the shaft generator should be used, what standby arrangements should be in place and when any change-over between generators should be timed.
When these incidents are viewed in isolation they are not extraordinary. However, when viewed collectively there appears to be commonality in the root causes; a lack of adequate procedures in company safety management systems and crew members failing to account for all factors when managing ship-specific power management systems.
When undertaking critical manoeuvres, use of the shaft generator should be carefully considered in accordance with the manufacturer’s guidelines. It is recommended that companies that operate vessels fitted with shaft generators review their procedures to ensure that Masters and Chief Engineers are guided accordingly.
It is tempting to speculate that rising bunker fuel costs and low charter rates may be a contributing factor, tempting some operators to run only minimal power plants during operations. However, this would need further verification by detailed analysis of changes in operating procedures
At recent Marine Environment Protection Committee meetings, concerns were raised that replacements for already under powered ships may be designed with main power plants that are even further reduced to comply with the requirements of EEDI. Greece recently expressed concerns, during MEPC 63, about potential under-powering of large tankers and bulk carriers, proposing Minimal propulsion power guidelines to maintain the manoeuvrability in adverse conditions from IACS, BIMCO, INTERCARGO, INTERTANKO and OCIMF for MEPC 64 in October.