The High Court has concluded that the Irish Aviation Authority should be temporarily restrained from using Dublin Airport's 32 million passenger planning conditions when setting slot coordination parameters for Winter 2025 and later seasons pending the outcome of ongoing litigation.
Aer Lingus, Ryanair and a group of US airlines sought the injunction. They are challenging the IAA's position that planning conditions limiting the combined annual capacity of Terminals 1 and 2 to 32 million passengers are relevant constraints under European slot-allocation rules.
Those planning conditions themselves are not being challenged in these proceedings.
Mr Justice Barry O'Donnell had already stayed a 25.2 million-seat cap imposed for Summer 2025. The substantive legal dispute was subsequently referred in part to the Court of Justice of the European Union.
The airlines argued that allowing similar caps for future seasons would cause serious losses. Ryanair said the Winter 2024 cap reduced its ad hoc pool slots from about 2,600 to 183 and resulted in 2,610 fewer flights and €35.8 million in lost revenue. It projected substantially larger losses if tighter caps were imposed for Winter 2025 and Summer 2026. Aer Lingus and the US carriers also identified potential losses of historic slots, revenue and market access.
The IAA maintained its legal view that the passenger conditions are relevant constraints but did not oppose the temporary injunction. daa opposed it, arguing that the statutory decision-making and consultation process should first run its course.
O'Donnell J rejected the argument that the court was improperly taking over the IAA's role. He found the proposed injunction simply removed one disputed factor from consideration while leaving the authority free to perform its remaining statutory functions.
The judge concluded that, without the injunction, the airlines faced serious and potentially irreversible harm and repeated litigation over each seasonal decision was likely.
He said the injunction should remain until the High Court determines the proceedings, with liberty to seek its amendment or discharge if circumstances materially change. Final wording and costs were left for submissions the following day.