Two of Europe's biggest airlines have been hit by strike action, grounding hundreds of flights and affecting tens of thousands of passengers, the BBC reported on Tuesday.
Lufthansa has been forced to cancel 800 of its 1,600 scheduled flights because of a walkout by public sector workers.
The stoppage is in force at Frankfurt, Munich, Cologne and Bremen airports.
At the same time, Air France has cancelled one in four of its flights as airline staff take action in support of a 6% pay claim.
Lufthansa has said about 90,000 passengers have been hit by the German public sector strike, which does not involve the airline's own staff.
Lufthansa told passengers whose flights had not been cancelled to allow more time to travel and get to airports earlier.
Meanwhile, Air France has said that it faces costs of €170m (£148m) from a wave of strike action by its employees, of which Tuesday's stoppage is merely the latest example.
The strike is set to continue on Wednesday, with further walkouts planned on four more days this month.