Frequently asked questions – North Runway Technical Group

Easterly departures only happen 5 to 10% of the time, don’t they?

No. daa itself says the wind is easterly about 30% of the time. Our own receiver data and ten years of airport weather records agree.

daa’s website: “When winds are easterly (about 30% of the time) … Runway 10R is preferred for departing aircraft.”
daa’s own planning application for the north runway hours (Relevant Action, December 2020) says the same: “approximately 30% of the time”.
Our ADS-B receiver at the airport: from 2 August to 8 November 2026, 26% of departures (9,562 of 36,799) took off towards the east, and 25 of the 97 days were mainly easterly.
Dublin Airport weather reports (METAR), 2016 to 2025: the daytime wind was mainly from the east on 34% of days, between 24% and 40% depending on the year.

But suppose it were 5 to 10%. That is 18 to 37 days a year. Once the north runway is needed for easterly departures, each of those days means:

at least 17 departures between six and seven in the morning over Malahide and its neighbours: 310 to 620 a year before seven o’clock;
about 24 widebodies to North America (A330s, 787s, 777s) over the town in the middle of the day: 440 to 880 a year.

At daa’s own 30%, it is about 110 days a year: about 1,900 departures before seven and about 2,600 widebodies.

Harm does not average out. A town that gets a jet every few minutes for a whole day does not suffer less because other days were quiet. And the airport sells its take-off slots for the worst wind, not the average one. For Dublin that is the easterly, so the easterly days decide how hard the north runway is used.

“If you ever flew on an airplane, you can never complain about airplane noise. Simple!”

No, any more than a train ticket is consent to a railway through your garden. How the airport is used was decided in planning: which runways, in which wind, at which hours, and along which routes. That use was assessed and conditioned. We do not object to flying. We object to the airport being used in a way nobody assessed.

If departures didn’t turn right towards Meath, wouldn’t they just fly over different people?

Yes, a different set of people. That is the problem.

When the north runway opened in August 2022, the departures turned onto ground that had never been overflown. Within 1.5 km either side of the routes flown today, 13,923 people live, and not one of them was under the old south runway routes. Within 3 km either side, 30,186 people are newly affected, and 29,452 of them (98%) would not have been affected by the straight route daa assessed in its Environmental Impact Statement. Nobody assessed the route they got, and nobody consulted them on it.

The move to the north runway was a chance to overfly far fewer people, and most of that chance was lost. People within 1.5 km either side of the departure track:

the old south runway routes: 20,048;
the routes flown today: 13,923, which is 31% fewer;
the straight route daa said it would fly: 2,888, which would have been 86% fewer.

So about 11,000 more people are overflown today than if daa had done what it said it would do and flown straight ahead.

Going straight out costs the airport no capacity. The departures were meant to go straight out, they could have, and they still can.

How many people does the turn actually affect?

Tens of thousands, in both directions.

Westerly departures, turning right over West Fingal and Meath: 13,923 people newly overflown within 1.5 km either side of the routes, and 30,186 newly within 3 km. Kilcoskan National School is among them.
Easterly departures, once the north runway is used for them, turning left over Malahide, Portmarnock and Drinan: 26,355 more people within 1.5 km either side of the routes, where the aircraft overhead are at 65 dB or louder.

None of these routes was the one assessed when the runway was given planning permission. That route went straight ahead.

“daa says there’s no such thing as planning permission for flight paths.”

daa did not always say so. Consulting the public on the north runway in 2017, daa wrote: “Determining flight paths is an important component in the preparation of the EIS relating to the Proposed Change to Permitted Operations.”

An Bord Pleanála’s permission of 2007 binds the runway to that Environmental Impact Statement and its Addendum (Condition 1). The Statement assessed departures flying straight ahead. Nine of the permission’s 31 conditions were set on those routes:

which runway is preferred in which wind, “in the interest of the protection of the amenities of the surrounding area”;
the limit on the crosswind runway;
the night limit;
insulation for five named schools and for the homes inside the predicted noise contours, installed before the runway opened;
voluntary purchase of the homes inside the loudest contour;
noise and flight track monitoring, to check that the mitigation works.

If the routes are not part of the permission, every one of those conditions protects the wrong people. The schools and homes were insulated under a route no aircraft flies, and the monitoring checks mitigation for people who are not overflown. A planning board does not impose nine conditions that cannot work. We have asked An Coimisiún Pleanála to decide the question.

But Fingal County Council accepts daa’s position that the planning permission doesn’t cover flight paths, right?

Fingal’s own grant said the opposite. When Fingal first granted permission for the north runway in 2006, its Condition 5 read: “Flight paths, aircraft approaches, and preferential use of runways in different weather conditions shall be as detailed in the EIS Addendum on file”.

The decision went to appeal, and An Bord Pleanála’s permission of 2007 replaced it. That permission binds the runway to the same EIS Addendum through its Condition 1. So the routes Fingal fixed in 2006 are in the permission the runway was built under.

Isn’t the turn a safety requirement?

No. The rules require a missed approach from the south runway and a departure from the north runway to split by 30 degrees. They do not say which one turns. The Irish Aviation Authority told the Oireachtas transport committee in November 2023: “In principle, the missed approach procedure for 28L could turn left”.

Turn the missed approach left, and the departures can fly straight ahead, on the route the planning permission was granted on. Instead the departures turn about 400 feet above the ground, and a turning aircraft climbs more slowly than one flying straight.

Doesn’t the turn give the airport more capacity?

No. Departures flying straight ahead from the north runway, with the south runway’s missed approach turning left, cost the airport no capacity. We gave daa and AirNav Ireland that proposal in October 2023. AirNav told daa in writing that “To fully assess the merits of this proposal, an Aeronautical study would need to be undertaken”. daa never asked for one.