Staff at two major airlines have threatened to strike this summer, adding to fears of more travel disruption.
More than 97 per cent of Lufthansa pilots voted in favour of industrial action earlier this week after their union demanded a pay rise.
The German airline received overwhelming support for a strike, however negotiations are still underway.
A strike could have a significant impact given the airline services 10 UK airports including London City, Heathrow, Edinburgh, Glasgow, Newcastle, Manchester and Cardiff.
Marcel Gröls, a member of the pilots' union 'Vereinigung Cockpit' said the vote was an 'unmistakable' signal that Lufthansa had to take the needs of the cockpit staff seriously.