Improving navigational safety

The key goal of navigation is the improvement of safety of navigation and collision avoidance. The current definition includes the statement ‘to enhance berth to berth navigation and related services, for safety and security at sea and protection of the marine environment’. With this stated objective it is useful to look at where and how recent incidents have taken place.

A recent report by the International Union of Marine Insurance shows a continuing downward trend of percentage of total losses of ships, decreasing from about 0.5 per cent in 1990 to about 0.1 per cent in 2006.

The total losses by number of vessels also continued to decline from about 180 in 1994 to 80 in 2006.

These statistics must also be viewed in the context of an expanding world fleet. Since 1998 the world fleet has increased by about 6,000 vessels and, coupled with the reduction in total losses, this indicates a general improvement in navigational safety.

However, when the causes of total losses and serious losses statistics are viewed, it is seen that total losses by grounding and collision have increased by four -five per cent and serious losses by grounding and collision increased by two-three per cent in the years 2002-2006, compared with 1997-2001.

A startling statistic noted in the investigation into causes of collisions and groundings is the large number of collisions that occurred when the OOW of one or both vessels was completely unaware of the other vessel until the time of the collision. In Seaways, Captain Nick Beer of the UK Marine Accident Investigation Board (MAIB) wrote; ‘In 43 per cent of all the collision cases involving merchant vessels that were investigated by the MAIB over a 10 year period, the watchkeeper was either completely unaware of the other vessel until the time of the collision or only became aware of the other vessel when it was too late to take effective avoiding action.’

This is almost entirely due to very poor watchkeeping, where lookouts are either not present or ineffective, and the OOW is asleep, fatigued, absent, distracted or totally disengaged with the tasks of keeping a safe navigation watch.

Despite advances in bridge resource management training, it seems that the majority of watchkeeping officers make critical decisions for navigation and collision avoidance in isolation, due to a general reduction in manning.

The IMO human element vision principles and goals (Resolution A.947(23)) contains the principle: ‘In the process of developing regulations, it should be recognised that adequate safeguards must be in place to ensure that a “single person error” will not cause an accident through the application of these regulations.’

And IMO MSC Circular 878 states: ‘A single person error must not lead to an accident. The situation must be such that errors can be corrected or their effect minimised. Corrections can be carried out by equipment, individuals or others. This involves ensuring that the proposed solution does not rely solely on the performance of a single individual.’

In human reliability analysis terms, the presence of someone checking the decision-making process improves reliability by a factor of 10. If navigation could assist in improving this aspect, both by well-designed onboard systems and closer cooperation with vessel traffic management (VTM) systems, risk of collisions and grounding could be dramatically reduced.

Collisions

Of the collisions investigated, 24 per cent were due to insufficient assessment of the situation, 23 per cent to poor lookout and, significantly, in 13 per cent of the collisions they were completely unaware of the other vessel until (or just before) they collided. Other causes were due to confusion of VHF communications, infractions of the Colregs, fatigue and OOW falling asleep, poor bridge management.

As shown in the case studies below, the number of incidents caused by insufficient assessment of the situation, poor lookout and the OOW being completely unaware of the other vessel should give cause for concern.

In the report of the collision between the bulk carrier Kinsale and the cargo vessel Eastfern on the morning of 25 September 2000, the MAIB noted: Causes of the accident were that, until shortly before the collision, Kinsale’s chief officer was unaware of the approach of his ship to Eastfern and Eastfern’s bridge team was unaware of the approach of the Kinsale. The visibility at the time of the accident was good although it was during the hours of darkness.

Similarly, in the report of the collision between the cargo ship Ash and the tanker Dutch Aquamarine on the afternoon of 9 October 2001, MAIB concluded: The OOW of the Dutch Aquamarine, which was the overtaking vessel, did not see the Ash until just before the collision. Again the collision occurred in good visibility.

Another example is the collision, in good visibility and sea conditions on the morning of 5 January 2004, between the bulk carrier Bunga Orkid Tiga and the fishing vessel Stella VII. The OOW on Maersk Dover received a VHF radio call from the deep-sea pilot on the Apollonia, advising him of the developing situation. Until than, the OOW of Maersk Dover was unaware of the presence of the Apollonia.

The report of the investigation by the MAIB again shows the dangers of single person errors. Their conclusion in the accident report was that this incident occurred: ‘as a result of poor watchkeeping practices and the OOW (Maersk Dover) becoming distracted by an incoming SAT C message; the OOW choosing to sit on a foot-rest while his view of the horizon was obstructed by bridge equipment; sufficient manpower was available on the bridge but the requirement to maintain an effective lookout had been ignored; when the OOW went to investigate the Sat C alarm, the last remaining visual safety barrier was removed. There was no longer a visual lookout or radar watch being maintained on the bridge of the Maersk Dover.’

Date: 2016-04-22; view: 804