Frankfurt Airport has been hit by strikes after talks with management broke down.
The latest strike got underway at 8pm Irish time and is expected to last until 4am.
Lufthansa has announced the cancellation of 140 flights tomorrow, particularly short and medium-haul journeys.
80% of long haul flights will not be impacted.
Some 200 apron control staff -- who direct aircraft in and out of their parking positions -- have been striking since 16 February.
They want higher pay, increased bonuses and shorter working hours.
Talks with airport operator Fraport broke down last Friday, opening the path for a new strike.
Fraport insists it had made concessions "on many points in the union's extremely high demands".
Frankfurt Airport, Germany's main hub, is Europe's third busiest after London-Heathrow and Paris Charles de Gaulle.
