A spokesperson said: "Despite regrettable and unjustified strike action taking place in 5 of our 37 markets on Friday (10 Aug), over 2,000 Ryanair flights (85% of our schedule) will operate as normal tomorrow carrying nearly 400,000 customers across Europe". But the figure could rise to 82 flights if routes between the Dutch city of Eindhoven and the Spanish cities of Reus and Valencia are finally canceled, after a court said on Thursday that Dutch pilots may join the walkout.
"For decades Ryanair has refused their employees basic labour rights most employees on the labour market take for granted, but here a strike is necessary to show the airline that it no longer can avoid treating its employees in a dignified manner", Martin Lindgren, President of the Swedish Pilots' Union, said in a statement.
"They tweeted: "£ryanair cancelled my flight in the last min because of pilots strike. The impact of the strike was limited with Ryanair apparently able to replace the striking Dutch pilots.
Past year it agreed to recognise unions for the first time but it is in a dispute over collective labour agreements.
Unions are pushing for better pay and conditions at Ryanair and want collective labour contracts governed by local laws, rather than Irish ones. Ryanair had filed for an urgent court order to prevent industrial action by pilots in the Netherlands.
French news source France Info dubbed the strike "historic", specifying that it is the biggest walkout in the history of Ryanair.
Irish-based Ryanair is Europe's largest low-priced airline.
But some people took to Twitter to complain at how Ryanair handled the debacle after their flights were canceled.
Another key complaint of workers based in countries other than Ireland is the fact that Ryanair employs them under Irish legislation, arguing most of its employees work on Irish planes.
He said they earn up to €190,000 (£170,000), which was more than their peers at budget rival Eurowings made.
At a Frankfurt press conference on Wednesday, Ryanair's chief marketing officer Kenny Jacobs said the company's German pilots enjoy "excellent working conditions".
Unions have strongly condemned what they see as Ryanair's attempts to play countries off against each other.
At Charleroi Airport, Belgium's second largest and a major Ryanair hub in the region, striking staff gathered in the departure hall and held up banners reading "Ryanair must change- Respect us".