The Irish Aviation Authority manages the air traffic in 500,000sq km of Irish-controlled airspace. About 1,000 aircraft fly through this area every 24 hours.
Traditionally, the aircraft route went from one ground-based radio beacon to the next, effectively zigzagging across the area. However, following improvements in on-board navigation equipment, pilots no longer had to rely on the beacons. So, aircraft were often cleared by the IAA to fly straight across its air space.
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