Evaluation of Navigational Aids using simulations
The use of Aids to Navigation (AtoN) should ensure that Mariners at all times are able to navigate safely even in bad weather such as high waves, strong current and wind, rain, snow, fog, etc.
It is important that vessels navigating an area (channels etc.) are confident of their position relative to the navigational channel and shallow waters, rocks, wrecks etc. Therefore, consideration must be given to the navigation aids available to the Mariner.
In recent years, as ships become larger, navigating in confined waters challenging the limits, it has become even more essential that correct design and placement of AtoN are done properly. Therefore, AtoN design and layout for a new navigation channel for an area requires thorough and proper evaluation to ensure safety and efficiency.
By validating the layout of new markings seen from the Mariner’s perspective in a simulator, it is ensured that the layout is fulfilling its purpose for the ships navigating the area. The conditions for which the buoys and lights can be used is then based on a navigator’s view rather than theoretical validations.
Safe and efficientIn general, the design of the channel markings is based on the recommendations and guidelines published by IALA, who recommends how markings should be designed and used globally, combined with calculations of light ranges, blink frequency, distances etc.
When it comes to safety, it is important that Pilots/Captains are confident when sailing in a certain area i.e. that there is sufficient space for stopping and manoeuvring, realistic environmental limitations and necessary aids to navigation.
Here a simulator based study is an efficient tool to test different configurations of AtoN, i.e. quickly rearrange markings, and simultaneously gather all the stakeholders (Authorities, Pilots, Captains) to observe and discuss in order to find the optimal solution for the AtoN for the area.
The simulator is also able to faithfully replicate lights and buoys with respect to distance, intensity, frequency, and conspicuity.
The Langesund marking project
The Norwegian Coast Authority (Kystverket) want to insert new channel markings for the area “Gamle Langesund” because of dredging to accommodate larger ships. The objective of the project was to test a suggested layout for aids to navigation, test PEL lights as opposed to front/rear lights and to test RACON on radar.
The Mariners were sailing the ships in one simulator and the stakeholders followed the scenario in another simulator. Thereby the stakeholders had the opportunity to experience the actual sailing scenario, had they been on the same bridge as the Mariner. The following discussions were then based on the exact same experience among the participants, however, without disturbing the Mariners while sailing the vessel.
The ship simulator is the ideal tool, as besides being mathematically accurate, it provides the opportunity to gather all the stakeholders (Management, Ship owners, Captains, Pilots etc.) in a realistic environment to experience real-life situations, thereby making the stakeholders aware of the advantages and limitations of the proposed marking design. In the end, consensus can be obtained of what is the best possible marking design and layout with respect to safety, efficiency and costs.
“The benefits are numerous as you get the layout assessed and tested before anything is built for a cost that is insignificant compared to the cost of placing marking that is not optimal risking loss as a consequence of an accident”, says Senior Project Manager, Steinar Hansen, Kystverket.
During the Langesund project it was found that a combination of PEL lights and front/rear lights was the optimal solution for leading lights in the “Gamle Langesund”. Additionally, it was found that certain lights and buoys needed to be moved, added or replaced to improve safety. This would probably not have been discovered without the use of a simulator.