A 24-hour strike at Irish airline Aer Lingus has grounded 202 flights and decimated traffic at the Republic of Ireland's three main airports in a union dispute over work schedules.

Aer Lingus jet (Aer Lingus)

Aer Lingus offered free refunds or rescheduled bookings to an estimated 28,000 passengers obstructed by Friday's protest by the IMPACT trade union, which wants three-day breaks between work periods.

The airline has suffered repeated strike threats from its unionized staff as it seeks to compete with Dublin-based budget airline leader Ryanair.

IMPACT leaders argue that Aer Lingus should allow cabin crews to work in a pattern of five days on duty and three days off, the schedule already provided to pilots. They say Aer Lingus sometimes makes flight attendants work six days in a row, with a single day off.

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