Changing Times, Challenging Times
by Seamus Doyle, Head of Engineering
We are living in changing times. Once upon a time a mouse was an untouchable mammal, now it is a handheld pest. When Lehman Brothers filed for Chapter 11 bankruptcy protection on 15 September 2008, it precipitated a major economic tidal wave that swept around the world. As in all sectors, this had a major effect on the maritime sector, with a dramatic reduction in world shipping trade. Despite this, it is essential to continue to maintain the safety of shipping though the provision of a first class aids to navigation service and the winds of change are blowing new ideas into the Aids to Navigation (AtoN) service. As with the computer mouse, the advent of satellite navigation systems has changed the face of navigation beyond recognition. The present economic climate has necessitated a reduction in activity, particularly in the capital investment area. Re-engineering projects have been deferred where possible and the focus is on projects where equipment replacement is essential to maintain the reliable performance of systems. Nonetheless, the maintenance, refurbishment, and replacement of obsolete systems continue in a busy schedule of work.
Dundalk Pile Light provides a significant inshore coastal route navigation mark to the sheltered anchorage of Dundalk Bay and the approach to the Port of Dundalk. The station was electrified in 1968. The mercury trough rotating optic apparatus was replaced with an energy efficient Pelangi PRL400 rotating beacon using 35 watt CDM-T lamps mounted on a Pelangi PA2 lampchanger. The red sectors were removed and the 360° light exhibited on 2 May 2008 with a range of 21 nautical miles (nm). A 6 nm emergency light comprising two Tideland ML300 lights with 10.3volt, 10 watt twin filament lamps was installed. The fog signal was replaced with a Pharos Marine SA850/3 2 nm omnidirectonal system controlled with a Biral VF500 fog detector. The Remote Control and Monitoring Ssytem (rcms) was updated with an energy efficient unit utilising GSM communications connection to Dun Laoghaire. The station is powered from mains electricity using a submerged cable from the shore. Mains fail backup is provided using duplicated 250Ah, 24 volt Sonnenschein A602/250 batteries.
Fanad Head Lighthouse, which has an 18 nm range in the white sector, marks the western side of the entrance to Lough Swilly. The two 14 nm red sectors of the light cover the off-lying dangers of Limeburner Rock to the west and the Swillymore Rocks to the south-east. Lying 7 miles to the south of a line joining Tory Island and Inishtrahull it is of benefit to passing vessels but is of greater significance to inshore traffic bound to and from the sheltered waters of Lough Swilly. The station was electrified in 1972 and a project to fully refurbish the station and replace the existing helicopter fuelling system has now been completed. The aviation fuel system, which was installed in 1990 was replaced with an integrated storage and dispensing system in a new location above the helipad. The redundant store rooms were converted into a mess room. Duplicated batteries and chargers were fitted and the mains fail generator set was retained. A new emergency light lantern was established above the main lens on a specially designed pedestal within the tower lantern. A cluster of four Osram M33 250 watt 24 volt lamps, under run at 19.5 volts, was fitted in the existing lens and first exhibited on the night of 24 March 2009. This design incorporates a standby light without lampchanger, since if one lamp fails, the remaining three lamps provide the required range.
The original light at Straw Island was established on 1 September 1878, using an oil lamp light source. The light was converted to unwatched acetylene gas on 30 September 1926 and then to electric on 23 September 1980 when the acetylene generating plant was replaced by an Aerowatt 300 watt, variable pitch rotor, 24 volt wind generator mounted on top of a steel mast in the lighthouse compound. This was replaced with a 2.3kW Proven machine during the 1990s. However the wind generators required a lot of maintenance and have been replaced with a solar power system. A new engine/equipment room building was constructed within the compound in front of the tower to provide adequate equipment rooms and storage at the station. The solar array comprises 30 solar panels mounted on a frame on the flat roof of this building high enough to avoid shadowing or damage by the sea. It is made up of two sub systems-the main power system and the engine start battery system. The main solar power system is made up of two arrays of 14 Solarnova 50D 50 watt 12 volt panels, with each array charging an Absolyte 24 volt 1700 ampere hour (Ah) gel electrolyte lead acid battery. The diesel generator was retained to charge an emergency 600Ah 24 volt A600/7/OPZV lead acid battery as well as providing backup power to charge the solar batteries and to provide power when people are on station. The engine start battery is continuously charged by the remaining two solar panels in the solar array to ensure reliable starting of the diesel generator set. Additional upgrading at the station include the updating of the rcms through the use of a GSM connection to the monitoring centre in Dun Laoghaire. The Pharos PRB46 MkI optic was replaced with two Tideland MaxLED-600 lanterns mounted in biform arrangement with synchronised flash characters. Two Tideland ML300 lanterns with 10 watt bifilament lamps were fitted on the balcony handrail to provide an emergency light. The new optic became operational on 29 May 2009.
Dun Laoghaire East/West Synchronisation
The East and West Pier Lighthouses guide shipping into the harbour of Dun Laoghaire. The character and colour of the light on the East Pier was changed in 1996 to provide a more conspicuous mark against the high level of background lighting created by the town and port facilities. This project further enhances the conspicuity of these AtoNs by synchronising their timing and flash character. A Wealth Marine type 4780A sectored 15 nm red led optic with a 7 nm sector towards the harbour, drawing 538 watts, was installed at Dun Laoghaire East to replace the old rotating lens apparatus. An 8 nm green led Wealth Marine WM-350A light was installed at Dun Laoghaire West and both lights were synchronised on 11 February 2009.
Donaghadee is an important light for vessels transiting the Donaghadee Sound, especially the clearing line delineated by the red sector for vessels approaching from the south. A full re-engineering project at the station was completed during 2008. The optic at this station was installed in 1967 and while the optic lens was retained, the L11 lamp source was replaced with a cluster of four 24 volt 250W M33 lamps providing a range of 17 nm white and 13 nm red. Batteries, chargers, lightning protection, remote monitoring and control system, fire protection system and tower facilities were renovated. The new optic was displayed on the night of 23 October 2008.
Buncrana pier light is an important light on the eastern side of Lough Swilly. Lough Swilly is a deep water inlet and a major port of refuge for vessels. The red sectors of the light also mark off-lying dangers and guide vessels towards Rathmullan. Over the winter of 2008 the old structures were removed and replaced with a prefabricated Pharos Marine GRP5.5 tower. The new 1.5m external diameter straight tower is approximately 5.25m high and has a life expectancy of between 20 and 30 years. Designed to withstand wind speeds of 160 kph the structure is Class 1 fire resistant as well as being impact and graffiti resistant. Additional protection against vehicle impact damage has been provided through the erection of stainless steel bollards around the base of the tower. Access to the lantern level is provided by internal ladder and access hatch on top. The new structure is finished as a red tower with a white band. The range of the light was reduced from 14 to 13 nm white and 11 to 10 nm red. The Tideland ML300 with 100 watt 12 volt lamps on a six position lampchanger was exhibited on 27 February 2009. The station is powered from mains with two 250Ah Sonnenschein batteries to provide backup.
The need for fog signals as aids to navigation continues to diminish. Haulbowline fog signal was discontinued on the 8 January 2009.
The character of the light on Mine Head Lighthouse was altered to Flash (4) 30 seconds on 7 November 2008 in order to improve the reliability of the optic system.
In recent years deterioration of the granite stone in the tower at Slyne Head has been observed. Remedial structural works which are sympathetic to the structure were carried out on the first and third tower floors of the tower to strengthen cracked granite blocks. A stainless steel thrust ring was bolted to the underside of the 3rd floor and a support angle was fitted to the damaged edge of the stairwell on the 2nd floor.
The footbridge across the gorge at Mizen Head providing access to the lighthouse was constructed in 1909 using partly precast and partly reinforced concrete. Following evidence of corrosion of the steel reinforcing, it was concluded that the bridge needed to be replaced. Agreement was reached with Cork County Council in August 2009 to transfer ownership of the existing bridge and an associated land holding to the Council, allowing the Council to carry out construction works associated with the footbridge replacement project. Cork County Council signed a contract for the replacement of the footbridge on 28 September 2009 with joint funding from Failte Ireland, Cork County Council and Commissioners of Irish Lights. Construction began in mid October 2009 with an anticipated completion time of one year.
South Rock ALF
A long era of lightships in Irish waters ended on 25 February 2009 when the last Automatic Lightfloat (ALF) Gannet, was permanently withdrawn from the South Rock station and a Type 1 buoy was established. The Type 1 buoy carries a heavy payload including duplicated synchronised 4 tier Vega VLB 44 LED lanterns flashing red to the same character as the ALF it replaced and providing a range of 9 nm. In the unlikely event of the buoy drifting off station the dual X/S band frequency agile Racon has the facility to automatically change to Code D. In addition, a fixed off-station light with a range of 5 nm would automatically come on. A duplicated hybrid solar/wave activated generator power system provides the energy for the equipment on the buoy and a duplicated AtoN AIS unit incorporating GPS and DGPS receivers provide autonomous position and AtoN status and alarm reporting directly to shipping in the area by means of the aiAISs message type 21.
The Codling and Arklow Lanby stations, originally lightship stations, have been marked with Lanbys since 1976. Two Lanby vessels were on station with a third spare vessel in Dun Laoghaire. These vessels have reached the end of their service life and, with advances in electronic positioning systems, the Lanbys are being replaced with buoys. Lanby C was taken off the Arklow Lanby station on 3 December 2008 and delivered to Hammond Lane in Dublin on 4 February 2009 for scrapping. On 24 August 2009 the type 2 South Arklow Buoy was permanently disestablished. On 25 August 2009 Lanby B was removed from the Arklow Lanby station and replaced by a Type 1 buoy at a new assigned position approximately 8 cables to the NNW of the previous position of the Arklow Lanby and named South Arklow. The new Type 1 buoy is equipped with a 7 nm led light, Racon and AIS.
Cardy Rocks Beacon
Cardy Rocks beacon was damaged some years ago by storms. Its repair work involved the erection of an access scaffold around the beacon, removal of the damaged topmark, preparation and painting of the structure, and the fitting of a new topmark.
Colt Rock Beacon
The Colt Rock Beacon is at the western approaches to Castletown-berehaven and has been unlit since the beacon was installed. The beacon was lit on the 10 October 2009. Wave washed scaffolding was erected on the rocks to provide a safe working platform to the top of the beacon. The original horse shaped Colt topmark was safely removed and the new light positioned at the top of the beacon, 7.5 metres above high water (HW). Special brackets were fitted to the pole of the beacon to enable a removable access ladder and fall arrest system to be easily attached and removed, thus allowing for safe access for future maintenance of the beacon. The new light is a Vega VLB 36 led integrated power supply lantern with solar panels on the three sides and the batteries housed within the unit behind the solar panels. The light has a range of 5 nm.
Blackhorse Rocks Beacon
Blackhorse Rocks Beacon is on the port side of the entrance to Crookhaven. The Beacon was first established in 1866/67. The original sphere top mark was replaced by cones in 1981. Using the same system of VLB36 lantern and scaffolding as on Colt Rock Beacon, the Blackhorse Rocks Beacon was lit on the 30 June 2009. A section of approx 600 mm was removed from the top of the beacon and replaced with the light unit and cardinal topmark, so that the overall height of the beacon has been increased by approx 1.5 metres. The height of light is 7.1 metres above hw and overall height of the structure above hw is 8.6 metres.
The buoy nomenclature used across the GLAs was not standardised, giving rise to on-going confusion. For example a CIL Superbuoy was classed as TH Class 1S9, a CIL Class 1 Buoy was a TH/NLB Class 2 Buoy. A single GLA buoy nomenclature as follows has been adopted to overcome this confusion.
• Buoy Type 1 (Light Focal Plane over 5m)
• Buoy Type 2 (Light Focal Plane 3-5m)
• Buoy Type 3 (Light Focal Plane 2-3m)
• Buoy Type 4 (Light Focal Plane less than 2m)
The 4 year buoy refurbishment interval was extended to a 6 year buoy program in order to formulate an all encompassing programme inclusive of buoy refurbishment, provision of AIS on buoys, implementation of the Navigation Review, and on-station maintenance in the most cost effective manner. This programme included the disestablishment of the Carlingford Buoy on 20 December 2008 and repositioning the Fundale buoy to its newly assigned position on 12 April 2009. Another milestone was reached on 3 July 2009 when the North and South Burford buoys, equipped with AIS AtoN and monitoring, were placed on station by ILV Granuaile and the whistle sound signals were discontinued, thereby completing the removal of sound signals on buoys.
South East Blackwater Buoy
The Southeast Blackwater Buoy was upgraded from a Type 2 to a Type 1 East Cardinal buoy and moved 0.8 nm to the east on 12 June 2009. The upgraded buoy consists of a Mobilis JET 9000 with a high visibility daymark and a 3 metre diameter polyethylene plastic hull providing 9000 kg of buoyancy. The buoy is fitted with a 6 nm range Vega VLB44 led lantern, a power system comprising four 80 Watt solar panels, regulators and batteries, a Martec Hekleo dual frequency X/S band Racon and a Pharos Marine single Atonis ais AtoN transponder.
In December 2005, IALA approved the trial deployment of Emergency Wreck Marking Buoys as impact signals to adequately and quickly mark new wrecks/hazards. IALA specified that emergency wreck buoys should be vertical blue and yellow stripes and display a blue and yellow alternating light with a nominal range of 4 nautical miles. Where multiple wreck buoys are deployed the lights should be synchronised and consideration should be given to the use of a Racon with Code D and/or an AIS transponder. The top mark, if fitted, should be an upright yellow cross. Trials of wreck marking buoys were carried out with ILV Granuaile on 9 February 2009. Two buoys-a converted Type 4 steel buoy and a Mobilis JET 2000 plastic buoy, conforming with IALA specification, were deployed in Killiney Bay. The buoys were viewed ILV Granuaile in daylight and in darkness at ranges of up to 6 nm. Both buoys successfully passed the trials and are deemed fit for purpose to warn shipping of any new dangerous wreck which are close to coastlines in depths or hazards where large commercial shipping would not generally navigate. They are also suitable for deployment in rivers, port channels and estuaries to warn mariners of the wreck's location and marking by the Ports Vessel Traffic Management System (VTMS) and pilot service. However these buoys are not suitable to mark new wrecks in open waters, Traffic Separation Schemes or Port approaches. A bigger buoy such as a Type 2 with Racon and AIS, would be necessary.
Light Intensity Tests
The objective of Light Intensity Tests is to confirm the published range of recently changed navigational lights and to test proposed optic arrangements for some of the re-equip projects. Tests in recent years have confirmed that the lights at Eeragh, Blacksod, St John's Point Donegal, Dunmore East, Fanad Head, Inishowen, Donaghadee, Old Head of Kinsale, and Youghal meet or exceed the advertised range.
The deployment of AIS AtoNs is continuing. AIS AtoNs were fitted on the Codling Lanby, South East Blackwater Buoy, South Rock Buoy and the North and South Burford Buoys. To date AIS AtoNs have been provided to mark stations where a lighthouse or buoy presently exists. In a sure sign of changing times, virtual AIS AtoNs are now available. A virtual AIS AtoN is broadcast from a shore station to mark a hazard where no physical AtoN exists thus a new wreck can be quickly marked with a virtual AIS AtoN buoy with a signal broadcast from a nearby shore station. Looking out the bridge window there are no buoys but looking at the electronic chart the wreck is marked with AIS AtoN buoys. Two Virtual AIS AtoNs (VAtoNs) were established, 25 miles east of the Baily lighthouse on 7 September. The transmissions are broadcast from the base station at the Baily Lighthouse and are monitored by the monitoring centre in Irish Lights Dun Laoghaire. The purpose of the trial is to consult with users on the usefulness of Virtual AIS AtoNs and to collect information to establish how the Virtual AtoNs are displayed on board vessels. The trial will run until 1 March 2010.
Replacement of the badly corroded DGPS aerial and mast at Tory Island was completed on 15 September. The wire T aerial is supported by the mast at one end and by the tower at the other.
Work in progress
Major re-equipping projects at Little Samphire, Kish, Inishowen, Galley Head, and Howth are progressing. Plans to relocate the directional light at Castletownbere and to replace the Codling Lanby are nearing implementation. Rollout of AIS AtoNs will continue on both fixed and floating stations. Storm damage repairs, routine and breakdown maintenance, painting and building operations continue to be carried out to ensure that Irish Lights not only meet IALA AtoN availability targets but also ensure that our structures, buildings and heritage are maintained in a cost effective and efficient manner. Times are certainly changing. Buoy fog signals have been withdrawn, lightfloats replaced with Type 1 buoys, the commencement of AIS AtoN service, virtual AIS AtoNs, commencement of Lanby withdrawal, reduction in the range and intensity of lights. Truly indeed changing times.
All this requires enthusiasm and hard work. My thanks and congratulations to all the Engineering Team for their dedication and commitment to deliver a splendid job.