Technical Session 3 – The future of visual aids to navigation Part 2
Chair: Mr Ómar Frits Eriksson (Denmark)
Vice Chair Captain Kieran O’Higgins (Ireland)
Aids to Navigation Design Framework for Channels, Mr Hendrik Eusterbarkey, German Federal Waterways and Shipping Administration
Presented by Mr Hendrik Eusterbarkey.
The presentation was made in an attempt to fill the “gap” between nautical expertise and technical AtoN expertise. Both are very highly developed in IALA.
The Aids to Navigation (AtoN) for fairways/waterways including dredged channels and canals should be both relevant to the mariner and cost effective to the National Authorities. A systematic approach and the use of performance parameters for defining requirements are proposed for the design of AtoN systems. Thus the approach of the e-Navigation concept is supported, considering at the same time, that a significant part of AtoN design is based on experience and good practise.
A short overview of requirements arising from documents of international bodies like IMO and IHO is included. Planning the horizontal and vertical dimensions of an approach channel is not part of the scope of AtoN design, but there is a strong interaction. The parameter ‘accuracy’ for vessel positioning, navigation and fairway width and its interdependence with buoy spacing is described and a new method from Japan for calculating the drift detection when using AtoN in a channel is explained. Some basic knowledge on perception of objects by human eyes and by other means is shared.
There is a need for a common understanding as there are many varieties, which are mostly motivated by different conditions regarding waterway and traffic patterns.
IALA documentation is extensive and can provide considerable guidance and should especially be considered regarding the use of specific technologies, e.g. the use of marine lights.
Steering a ship in a waterway is a process which is determined by different factors as;
• Interaction between ship and fairway,
• Fairway width, bank clearance, fairway depth, bottom surface,
• Wind, waves, currents, tide,
• Ship manoeuvrability, speed,
• On-board-equipment,
• Capability of the navigator.
IMO Resolutions A.915(22) “Revised Maritime Policy and Requirements for a Future Global Navigation Satellite System” and A.953(23) “World-Wide Radionavigation System” show a variety of parameters. Not all of them may be applicable to all AtoN. However, the parameters reflect different properties which single AtoN or AtoN systems can have. Therefore it is useful to take some of these parameters into account when defining the requirements for a specific channel or a type of waterway.
The key points of the presentation were:
1 A systematic approach and the use of performance parameters for defining requirements for the design of AtoN systems support the e-Navigation concept.
55 The AtoN design for a fairway has to take into account the IMO and IHO requirements and waterways design (hydraulic engineering).
56 The accuracy for vessel positioning and drift detection is significantly depending on buoy spacing.
Visual Marking of Offshore Wind Farms, Mr Rainer Strenge, Mr Raven Kurtz, Mr Philip Giertz, German Federal Waterways and Shipping Administration
Presented by Mr Rainer Strenge.
Offshore wind farms play an ever-increasing role in plans to expand the use of wind energy in Germany. However, from a nautical and aeronautical point of view a wind farm is a man-made obstacle which potentially affects safety. Whilst shipping traffic can be heavy at times so can aeronautical traffic, in the form of many helicopter flights including those used by the SAR services.
The large offshore wind farms planned in the German part (Exclusive Economic Zone) of the North and Baltic Seas will be 30 – 100 kilometres from the coast, in deep water, very close to highly frequented shipping routes. As a consequence, several measures will have to be carried out in particular to maintain safety of shipping. This includes the need for sufficient marking offshore wind farms.
During the approval process several conflicting demands from different stakeholders have to be considered in order to find a solution that will ensure the maximum level of safety for shipping and aviation. In addition an appropriate level of environmental protection as well as minimum burdens and low costs for the operating companies are aspired. This applies particularly to the visual marking system.
To ensure safety of navigation for both shipping and air traffic the large wind farm structures have to be clearly marked. Therefore, the German Federal Waterways and Shipping Administration have developed a "Guideline for design, marking and operation of offshore wind farms (FWA Guideline)".
The presentation introduces technical solutions for the visual marking system implemented in Germany based on IALA Recommendation O-139 and ICAO Annex 14. They harmonize the nautical and aeronautical requirements of lights while also minimising light pollution. Finally, the concept of computer-based simulations for assessing visual marking systems was considered and a short video clip was shown demonstrating this.
The key points of the presentation were:
1 Offshore wind farms.
57 Visual marking.
58 Obstacle light.
59 Short range marking.
60 Simulation.
The Wider Application of LED Light Sources into Historic Lighthouses, Mr Peter Kelly, Trinity House
Presented by Mr Peter Kelly.
Over the years the transition in light source style has seen moves from the Paraffin Vapour Burner through physically large high wattage tungsten filament electric lamps then to high power High Pressure Mercury Vapour lamps down to low wattage Metal Halide and Tungsten Halogen lamps. The various light sources used over the years was discussed together with the advantages and disadvantages of using the more modern LEDs.
Some of the advantages are;
1 Relatively simple to operate
61 More robust
62 More efficient
63 Easily switched on and off.
The use of LED light sources is now widely accepted as a practical and inherently reliable method of exhibiting a navigation light from various different platforms. The application of LED light sources in historic lighthouses attempts to integrate the very modern with the traditional in as sympathetic, yet effective, a manner as possible.
This presentation reviewed the circumstances in which the employment of LED light sources is appropriate and offered solutions to the use of LED light sources in historic optical apparatus as well as the application of non-integrated solutions where it is appropriate to leave the historic optical apparatus in place and exhibit the light from self-contained unit(s).
Research into the application of a chip type of LED array is underway by the UK GLA R & RNAV Directorate (Sept 09). The application of these devices will enable the reuse of an historic optic, and when driven by a highly efficient DC drive motor (average power to drive a 1st order optic is approximately 8 watts) to be reliably powered from a renewable energy source such as photo-voltaic.
The key points of the presentation were:
1 Flexibility of approach to the application of LED light sources.
64 The progression of light sources through the years.
65 Achieving a cost effective solution.
66 The effect of a small light source in a tradition optic.
67 Future approaches and opportunities.
Development of Flickering Light, Cdr Hideki Noguchi, AtoN Engineering Division, Maritime Traffic Department, Japan Coast Guard
Presented by Cdr Hideki Noguchi.
Due to both the number and intensity of lights, such as port lights, security lights and city lights the light of marine aids to navigation is becoming buried in these lights and thus marine aids to navigation in such situations need to be more conspicuous. The Japan Coast Guard and Japan Aids to Navigation Association have carried out research into a new lighting method of LED including field experiments and have developed a flickering light, which is a combination of conventional flashing pattern and flicker. This flickering light has obviously an excellent conspicuity especially at close range. In addition to the research, the Japan Coast Guard also held an expert meeting on conspicuity inviting visual experts from CIE and IALA under the auspices of the Ocean Policy Research Foundation in November 2008. The presentation reports the development work of the flickering light and the result of the expert meeting. Additionally the presentation also reports the latest field experiment; using an existing lighthouse in Yokohama and its result. The experiment used a red light flashing every 3 seconds. The results showed that the Flicker type light was more apparent to the human eye than the conventional one.
The presentation showed that the flickering flash light has a good conspicuity and this effect covers three main colours of aids to navigation light, white, red and green. It is therefore said that the flickering flash light will become one of countermeasures against background lighting problem that is recently emerged as a serious problem in the visual aids to navigation field.
The past countermeasures conducted by JCG such as synchronization of lights, floodlighting of structure required additional cost and power consumption. Compared with these past countermeasures, the flickering flash light is relatively inexpensive and the power consumption is the almost same as the conventional LED lantern.
The key points of the presentation were:
1 Conspicuity.
68 LEDs.
69 Flickering Light.
Discussion – Technical Session 3 – Part 2 (papers 5 - 8)
Cdr Noguchi was asked if the Flicker light experiment showed the result for 3 or even 5 miles? He replied that the Flicker light experiment was only carried out for 2 miles and that this distance was found to be very useful; further experimentation will be required for greater distances.
It was observed that an experiment with Flicker light was carried out in Copenhagen and it was found that it is largely dependent on the lamination effect on the human eye. It was also only apparent at short ranges.
Cdr Noguchi was then asked if, during the experiment, the Flicker light was ever confused with a quick flashing light? In replying, he said that out of 200 responses only 1 thought it was a quick flashing light but from an ambulance on the shore!
Rainer Strenge was asked if the specification, mentioned in his presentation, be provided in the English language. The response was that the specification can currently be downloaded from the GFW website, in German. However, it is hoped than an English version will soon become available.
Hendrik Eusterbarkey then said that the HIWUS study, which deals with the impact on the environment, is available in the English language for those who are interested.
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