North Atlantic Communications Service
The IAA's North Atlantic Communications Service is provided from its communication station located at Ballygirreen, Newmarket-on-Fergus, Co. Clare and covers the Eastern half of the North Atlantic. It is known as Shannon Aeradio, or Shanwick Radio (ICAO Code: EIAA). Approximately 70 personnel are employed at the North Atlantic Communications centre, including over
55 Radio Officers with the remainder involved in engineering, administration and other services.
Three aeronautical services are provided:
1.
Aeronautical Mobile Service - Air/ground operations (Shanwick Radio)
Shannon Aeradio provides a long range voice communications service for
Oceanic Air Traffic Control in the eastern half of the North Atlantic. The Oceanic Air Traffic Control Centre is located at
Prestwick in Scotland, hence the name
Shanwick (Shannon/Prestwick).
Shanwick Radio keeps in contact with all flights in Oceanic Airspace mainly by means of High Frequency Radio (HF), but also uses VHF (Very High Frequency) and Satellite Phone (SATPHONE). HF can provide global coverage because of its ability to bounce off the ionosphere and can span the globe in a series of skips. VHF coverage, on the other hand, is limited to line-of-sight range. Shanwick Radio uses over 20 HF frequency channels and 2 VHF. At peak times it handles in excess of 1300 aircraft in a 24 hour period. In 2007, the station handled in excess of 1 million messages from 414,570 aircraft.
In recent years the IAA has invested significantly in new systems providing the North Atlantic Communications operation with state of the art facilities and bringing the service up to the most modern standards. A new suite of transmitters and receivers has been installed and the Air-Ground message processing and flight data system replaced.
This system, known as the ROFDS (Radio Officer Flight Data System), which is linked to a similar system in the Iceland Radio centre, has enabled the Irish Aviation Authority and ISAVIA (the Icelandic Civil Aviation Administration) to provide joint radio operations for the Shanwick and Reykjavik/Sondrestrom Oceanic areas. Formal agreement between the two companies was signed in 2004, and in April 2006 joint operations commenced creating, in effect, one virtual radio station for the North Atlantic from 45N to the North Pole. Radio officers in either centre can and do work flights in either area, updating both systems seamlessly and transparently for the respective Control Centres in Reykjavik and Prestwick.
2.
Aeronautical Fixed Service - AFTN
In addition to the North Atlantic Communications Service, Shannon Aeradio is the AFTN COM centre for Ireland. The Aeronautical Fixed Telecommunications Network (AFTN) is an international telegraphic service linking airline offices, ATC and meteorological services worldwide. All AFTN communications both in and out of Ireland are routed through the Ballygirreen AFTN computerised message switch.
3.
Aeronautical Broadcast Service - Volmet
Another service provided to the aviation community from Shannon Aeradio, is the Volmet Broadcast Service. This is a 24 hour, 365 day-a-year continuous broadcast of weather data to aircraft in flight. The data consists of Sigmets (warnings of significant weather phenomena which may be hazardous to aircraft), terminal forecasts and actual weather observations for each of the principal airports in Europe. These reports are updated every 30 minutes. This broadcast, although intended for aircraft approaching Europe, has become very popular with Short Wave listeners the world over, and results in large bags of "fan mail" every year. The broadcast goes out on three HF and one VHF frequency simultaneously.
