Europe’s largest low-cost carrier has faced multiple strikes since last December, when it bowed to pressure to recognise trade unions for the first time. Staff have stepped up pressure in talks over pay and conditions.

Cabin crews in Germany, Belgium, Portugal, the Netherlands, Spain and Italy, as well as pilots in Germany, began a 24-hour walkout as airspace opened on Friday. “They don’t care about us. We are just numbers. We are lemons to be squeezed and thrown away,” said Juan Fernandez, a former Ryanair employee who joined protesters at Brussels airport.

Ryanair said that more than 2,150 of its 2,400 scheduled flights would operate…