The High Court will hear an application from Ryanair today for an order to prevent this week's pilots' strikes.
180 Irish-based pilots are due to take part in strike action on Thursday and Friday in a dispute over pay and conditions.
Lawyers for Ryanair say the Irish Airline Pilots Association (IALPA), whose parent union is Fórsa, walked away from mediation talks last week before they even got going.
The airline also claims the proposed strikes would breach an agreement both sides signed up to last year - and that the pilots haven't made clear exactly what they want.
They say the timing of the planned strike - right in the middle of school holidays - is aimed at causing maximum disruption to passengers.
Today, Ryanair's application for an injunction to stop the 48-hour strike going ahead will be heard by the High Court.
The union has previously said pilots feel they have been forced into the industrial action.
They have accused the airline of being "unwilling or unable to negotiate in a professional and constructive manner".