Tens of thousands of Ryanair passengers across Europe are suffering disruption as strikes cancel 250 flights.
Unions claim this is the biggest day of action yet against a series of complaints about conditions by Ryanair workers in a raft of countries.
Ryanair say 35,000 passengers have been affected.
But it added 90% of flights would operate as normal. Some 20 flights to and from Ryanair's biggest European hub, Stansted, have been cancelled.