The Irish Aviation Authority (IAA) has recently published its first report on the operational environmental performance of aviation organisations in Ireland. Covering January to June 2026, it uses EUROCONTROL data to look at how airlines, air navigation and airports influence fuel burn and CO₂ emissions through their day-to-day operations. It is the first report of its kind from the IAA.
En-route: AirNav Ireland Second in Europe
The headline for air navigation is positive. AirNav Ireland ranks second best in the European network for en-route efficiency. The measure used is horizontal flight efficiency (KEA), the average extra distance flown compared with the most direct route. Ireland’s figure for H1 2026 was 1.53%, down from 1.63% in 2025, although still short of the national target of 1.40% for 2026. The report notes that some factors lie largely outside AirNav Ireland’s control, including UK free route airspace, North Atlantic routing changes and the inclusion of Icelandic airspace in the measurement area.
Continuous Descents: Ireland Ahead of Europe
A continuous descent operation (CDO) lets an aircraft descend from the top of descent in a smooth, low-power profile rather than levelling off in steps. It reduces fuel burn, CO₂ and noise. EUROCONTROL estimates a continuous descent can save around 46kg of fuel, or 145kg of CO₂, per flight.
Irish airports averaged 40.9% of flights achieving a continuous descent in H1 2026 (41.6% in 2025), well above the European average of 34.0%. The rate varies widely by airport, however:
- Donegal, Kerry and Ireland West recorded monthly rates of roughly 70% to 82%.
- Shannon ran at around 58% to 62%.
- Cork ran at around 50% to 55%.
- Dublin ran at around 35% to 39%.
Dublin handled 63,000 of the 77,000 descents counted at Irish airports in H1 2026, so it largely sets the national average. This is likely due to the Point Merge arrival system which requires many arriving aircraft to fly level at FL70 or FL80 during the approach, significantly increasing fuel burn. Across the three AirNav Ireland-towered airports (Cork, Dublin and Shannon) the rate slipped from 40.5% in 2025 to 39.6% in H1 2026, while the other Irish airports with scheduled services improved from 65.8% to 70.4%.
Ryanair Sets the Benchmark
The airline-by-airline comparison is where the report is most striking. At Dublin, Ryanair achieved a continuous descent rate of 58.4%, against an average of 37.2% for all other operators. Across its whole operation, the Ryanair group recorded 44.1% in H1 2026, compared with a European airline average of 34.5%, and the IAA describes it as the benchmark across Europe.
For Irish-based or Irish-linked operators as a whole, the rate fell from 42.7% in 2025 to 39.3% in H1 2026. Excluding Ryanair, it was 34.9%. The report also charts SAS Connect, Fly4 Airlines, ASL Airlines Ireland, Emerald Airlines and Aer Lingus, though the figures for those operators are shown only in a chart.
Taxi Times Improve at Dublin and Cork
On the ground, both Dublin and Cork improved. Average departure taxi time at Dublin fell from 4.18 to 4.11 minutes and arrival taxi time from 2.06 to 1.90 minutes. At Cork, departure taxi time fell from 2.48 to 2.35 minutes and arrival from 0.97 to 0.80 minutes. There’s no detail in the report indicating how this is measured, as anecdotal evidence would indicate taxi times in reality are significantly longer. The European arrival average rose slightly over the same period. Context matters, though: Dublin still ranks 75th of 88 European airports for departure taxi time, while Cork ranks 12th.
The report also flags early-morning holding at Dublin. Between August and December 2025, 56 of 193 early arrivals were held for 12 minutes or more, a change linked to the prioritisation of first-wave departures. The IAA says it will keep monitoring this.
Growth is the Backdrop
The efficiency figures sit against rising traffic. Irish airports handled 157,515 flights in H1 2026, up 6.7%, and CO₂ from departing flights reached about 1.7 million tonnes, up 7.0%. Longer-term decarbonisation through new technology, fleet renewal and sustainable aviation fuel is outside this report’s scope. It looks only at short-term operational efficiency measures, which the sector’s 2050 decarbonisation plan expects to deliver around a 6% reduction in aviation emissions.
A Note of Caution
The IAA is clear that no single metric captures environmental performance. Results are shaped by airlines, airports and air traffic service providers, as well as weather, traffic levels, military airspace activation and airspace design. The CO₂ figures cover departing flights only, and the report is for information rather than a replacement for statutory reporting. All data is publicly available from EUROCONTROL. The next edition, covering H2 2026, is due in early 2027.
