The airspace of the Republic of Ireland has reopened after flights to and from the country’s two primary airports – Cork (ORK) and Shannon (SNN) – were suspended on the evening of October 2, 2018, due to a significant radar issue. The third hub – Dublin Airport (DUB) – remained unaffected, however a number of flights, including transatlantic, have been delayed or diverted.

According to statements made by the Irish Aviation Authority (IAA), on the evening of October 2, 2018, the flow of air traffic was "restricted” as a precaution due to a technical issue at Shannon’s Air Traffic Control (ATC).

Aviation24 news portal reported failure of the Flight Data Processing System (FDPS) in Shannon. Meanwhile, the European Organisation for the Safety of Air Navigation or Eurocontrol, issued a notice stating the Shannon (ICAO: EISN) has encountered a ””complete radar failure”.

The technical failure prompted a zero-rate regulation in the Irish airspace, which was initially set until 22:00 UTC and then extended to apply until 23:00 UTC. Meaning, that until late into the evening, the Irish airspace was closed down, with flights forced to be delayed or diverted. including several transatlantic flights, which had to be re-routed to avoid the Irish airspace.

As of the morning of October 3, 2018, most flights were expected to operate as scheduled. A Cork Airport spokesperson confirmed that flights have resumed at the hub, the Independent Irish News reported.

According to the spokesperson, there was a significant systems failure with radar in the west of Ireland impacting all flights coming from the west/south. This resulted in the zero-flow-rate in the Irish airspace.

As part of its contingency plans, the IAA stated it had deployed its back-up radar systems before the flight restrictions could be lifted. During that time, Dublin Airpot remained open to air traffic, as it is the only airport in Ireland that does not use Shannon’s ATC system.

„The IAA’s Dublin ATC system is unaffected and Dublin flights are operating normally. The Dublin ATC is independent of the Shannon system", one of the updates on the agency‘s website said. „The technical issue is with the IAA’s Shannon-based system, which also services Cork – hence the earlier impact on Shannon and Cork."

The IAA is the agency which, aside from regulating Irish aviation, is responsible for providing ATC in the Shannon Flight Information Region (FIR). The regulator has opened an investigation into the causes of the technical issue.