Lufthansa will be effectively crippled with more than 425,000 passengers affected by a three-day strike by pilots over pay and working conditions.
Lufthansa and Germanwings have cancelled about 3,800 flights on Wednesday, Thursday and Friday.
Only about 500 Lufthansa short and long-haul flights will be operated during the three-day walk-out.
The industrial action on three consecutive days is one of the biggest walkouts in Lufthansa’s history.
However, pilots at group airlines Swiss International Air Lines, Austrian Airlines, Brussels Airlines, Eurowings, Lufthansa CityLine and Air Dolomiti are not involved.
Lufthansa plans to re-book affected passengers on other airlines and German Railways (Deutsche Bahn) will provide train tickets on domestic routes.
Additional staff are being drafted into the main hubs of Frankfurt and Munich to handle passengers.
“Waiting passengers will be taken care of as well as possible there,” the airline said
A list of cancelled flights is published on lh.com. Information for Germanwings passengers is available on germanwings.com.
Lufthansa legal and personnel executive board member Bettina Volkens said: “I greatly regret that the [union] Vereinigung Cockpit is not prepared to settle this by negotiations and to find a solution without engaging in a labour dispute.
“We made good offers for an improved salary as well as a future provision for early leave from flight service.
“Based on this it is difficult to understand that the VC union is calling for a three-day strike right away – both for our customers and the more than hundred thousand colleagues of the other Lufthansa employee groups.
“We will do our best to care for our customers during the strike. I want to thank in advance all employees that will go above and beyond what is normal and give their best for our customers and for the company.”