Seven major German airports have been brought to a standstill after hundreds of ground crew walked out on strike in a row over pay.
Aircraft are grounded at Frankfurt, Munich, Stuttgart, Bremen, Hamburg, Hanover and Dortmund.
More than 2,300 flights have been cancelled affecting 300,000 passengers, with air travel effectively wiped out.
Members of the Ver.di union and Civil Service Association are demanding a 10.5% pay increase for workers.
At Leipzig Airport, a handful of international flights got away this morning but domestic flights were cancelled.
At Frankfurt Airport, a couple of passengers wheeled suitcases through what is usually the bustling departures terminal. It was, one local TV reporter noted, almost as empty as it had been during the Covid pandemic.
Airports handling emergency aid for earthquake victims in Turkey and Syria have said that those cargo flights would continue as scheduled.
But the strike – which comes two days after Frankfurt Airport cancelled 200 flights when building work knocked out Lufthansa’s online check-in and boarding systems – has prompted a furious response from some German business leaders.
Representatives of small and medium business associations condemned the action as unacceptable and accused the unions of taking the whole country hostage for their own interests.