Why are planes circling over Dublin?

What a holding pattern is

A hold is a way of delaying an aircraft that is already in the air while keeping it inside a known piece of sky [1]. The standard pattern is a racetrack around a fixed point, flown with right-hand turns: two one-minute turns and two one-minute straight legs, about four minutes a lap [1]. Above 14,000 feet the straight legs stretch to a minute and a half [1].

When several aircraft are waiting at the same point they are stacked, each at least 1,000 feet above the next. New arrivals join at the top and the lowest aircraft leaves first to start its approach, with everyone else stepping down a level [1]. Aircraft hold when they have reached their destination but cannot land yet: too much traffic, bad weather, or a runway that is not available [1].

Dublin rarely stacks any more

If you picture a tower of aircraft circling over Fingal, Dublin mostly stopped doing that more than a decade ago. In December 2012 the Irish Aviation Authority introduced Point Merge for arrivals to runway 28, later extending it to runway 10 [2]. Instead of racetracks, arriving aircraft are placed on defined arcs, every point of which is the same distance from the runway. From the arc each aircraft makes a single turn towards the airport and descends continuously to land [2].

The IAA says this has almost eradicated the need for traditional circular holding at Dublin [2], and AirNav Ireland, which now runs air traffic control, says the same [3]. On runway 28 alone it saved airlines €5.5 million and 23,500 tonnes of carbon dioxide over 2013 and 2014 [2].

What this looks like on the live map is a string of arrivals following a long curve at the same height, then peeling off one by one towards the runway. It can look like circling. It is really queueing.

Where Dublin’s holds are

The holds still exist for when they are needed. Ireland’s official aeronautical publication names the entry holds at the start of the sequencing arcs: KERAV and SORIN for arrivals to runways 28L and 28R, ADNAL and BABON for runways 10L and 10R [4]. An aircraft that loses its radio, for example, is told to fly its arrival route and enter the appropriate one [4]. Arrivals for the crosswind runway, 16/34, plan to reach 6,000 feet at their hold [4].

Slow light aircraft have visual holds of their own, marked by landmarks you may know: the M1 bridge over the Broad Meadow estuary (at least 1,000 feet), the Palmerston roundabout where the M50 meets the N4, and Marley Park House (both at least 1,700 feet), each with one-minute legs flown at 90 knots [4]. A small plane going round and round above the M50 may simply be waiting there.

When it happens

• Too many arrivals at once, or too few controllers. In November 2023 Dublin’s airspace was closed twice because not enough air traffic controllers were available, and seven transatlantic flights circled over Knock for up to 40 minutes [5].
• The runway stops. When a drone was reported on 4 August 2023, flights were suspended for about ten minutes, two were diverted to Belfast and other aircraft had to hold for a very short period [6].
• The wind changes. Aircraft land into the wind and air traffic control picks the runway on weather, safety and planning grounds [8]. On 31 August 2025 unusual southerly gusts of about 30 knots forced several runway changes and nine diversions [7]. Every change reshuffles the arrival queue.

Go-arounds

Sometimes the loop happens at the last moment. If a pilot judges that a safe landing cannot be made, they abandon it: engine power goes up, the aircraft climbs away and loops round to rejoin the landing traffic, on special paths that keep it clear of other arrivals and departures [9]. It is a normal procedure, not an emergency. Wild days bring many: when Storm Dave hit on 4 April 2026, Dublin recorded 53 go-arounds and 13 diversions [10].

On the map, a go-around shows as an arrival that reaches the runway, climbs out ahead and swings round for another try.

Other aircraft that circle

Not every circling aircraft is an airliner. Garda helicopters orbit over incidents, survey aircraft fly grids, and training aircraft go round airfields. Our guide to why a plane is flying low over your house covers them. To find out which you are looking at, open the live map and tap it: Skylark draws the track it has flown, so a hold, a go-around and a search pattern are easy to tell apart.