As many as 15,000 passengers of the low-cost airline Germanwings were left in limbo as pilots walked out on Thursday morning in a row over pension rights.
The six-hour strike, which lasted until midday local time, affected more than 100 mostly domestic flights from secondary airports including Cologne-Bonn, Stuttgart and Hamburg.
Gudrun Besser, one of the passengers affected by the walk-out, was less than impressed.
“You work hard all year and save money for your holiday, and then there is a strike right in the middle of the tourist season. I have no sympathy,” she said.
Vereinigung Cockpit, the main pilots union, is a small but powerful syndicate, which wants to maintain early pension rights at 55.
But the company plans to raise the average retirement age from 59 to 61.
On Thursday, Germanwings, which is owned by national carrier Lufthansa, appealed for further talks.
Additional walk-outs could be decided over the weekend.
In April, a three day strike over the same issue cost Lufthansa some 60 million euros.