EasyJet staff are planning more strikes over July due to work conditions and pay.
Spanish workers with the budget airline left their positions between 1 July and 3 July after negotiations with the company failed.
This kicked off industrial action which is set to rock the aviation industry further after chaos in recent weeks has seen travellers face cancelled flights and long airport queues.
Members of easyJet staff in the UK have not announced industrial action, but members of the Spain USO Union are taking action with more than 450 cabin crew members called to strike.
When will easyJet strikes happen?
More easyJet industrial action is planned for 15, 16, 17, 29, 30 and 31 July.
An easyJet spokesperson said the airline plans to operate its full schedule and would do everything possible to minimise disruption.
According to aviation news network FL360aero, nine easyJet flights were cancelled and more than 590 delayed due to the strikes which took place between 1 July and 3 July.
On 1 July alone, four flights were cancelled, with journeys from London and Birmingham affected.
Which airports will be affected?
Strike action in July is likely to affect easyJet bases in Spain, which are Barcelona, Malaga and Palma.
The strikes scheduled for the end of July could impact British tourists trying to get away for the school holidays.
The company said: “Should the industrial action go ahead, there could be some disruption to our flying programme to and from Malaga, Palma and Barcelona during the strike period but at this stage, easyJet plans to operate its full schedule and we would like to reassure customers that we will do everything possible to minimise any disruption.”
Why are easyJet workers striking?
USO said: “Spain’s cabin crew has the lowest basic income of all European easyJet hubs.
“If you fly a lot of hours, you end up paying your invoices but reducing your break time and doing a higher number of flight hours.”
USO has said its members in Spain typically have a base salary of €950 a month – €850 less than easyJet cabin crew receive in France and Germany.
The union has been in a dispute with the airline since February.
How else has the airline been affected?
The budget airline has been hit with chaos over the last few months with numerous delays and cancellations due to issues with staffing.
EasyJet’s chief operating officer, Peter Bellew, also resigned on Monday (4 July).
Chief executive Johan Lundgren said: “I would like to thank Peter for his hard work and wish him well.
“Everyone at easyJet remains absolutely focused on delivering a safe and reliable operation this summer.”
The airline has struggled with staff shortages in the UK and had issues recruiting employees for the summer peak period.
Are workers at other airlines striking?
British Airways workers at Heathrow are set to strike in July after voting for action over an ongoing pay dispute.
The dates of the planned strike are yet to be determined but it is likely to be during the school summer holidays.
Ryanair workers in Spain are also taking strike action this summer with 12 additional days announced yesterday. Employees are striking over working conditions.
Ryanair bases in Barcelona and Malaga are likely to be affected.
Ryanair CEO, Michael O’Leary, has said he expects flight prices to rise over the next five years and has blamed Brexit for some of the current chaos, calling it a "disaster".