The Irish High Court has granted leave to Ryanair (FR, Dublin International) and Aer Lingus (EI, Dublin International) to challenge a draft decision by the Irish Aviation Authority (IAA) to impose a passenger seat cap at Dublin International Airport for the Winter 2024/25 season.

The IAA's decision limits passenger numbers to just over 14.4 million from October 27, 2024, to March 29, 2025. Both airlines argue that the decision is legally flawed and should be set aside. They allege that the IAA acted outside its powers and jurisdiction and irrationally. They also claim the IAA failed to provide adequate reasons and violated their constitutional rights, including property rights, reported The Irish Times and the Irish Independent newspapers.

High Court judge Niamh Hyland, separately, granted permission to Dublin Airport Authority (DAA) to challenge the IAA's decision, reported The Irish Times. The DAA argues that the "Winter 2024 coordination parameters" set by the IAA exceed the capacity constraint stipulated by planning permissions for the airport, which limits annual passenger numbers to 32 million. The DAA further contends that these parameters might also contravene European Union regulations.

Ryanair's CEO, Michael O'Leary, has stated the airline could lose over a million seats, amounting to nearly EUR90 million euros (USD97.6 million) in potential revenue. Aer Lingus highlighted impacts on winter services like flights to Lapland for Christmas and ski resorts in Europe.

The cases have been adjourned for further proceedings.

ch-aviation has reached out to all parties for comment. Ryanair declined to comment further at this stage, while the DAA referred to its reported challenge of the IAA's decision.