Travelers are facing widespread disruption after a dispute at Germany's flag-carrying airline Lufthansa gathered momentum this week.

The dispute began with a walkout last week by cabin crew represented by the UFO union.

Then, Vereinigung Cockpit, the union that represents Germany's pilots, called a two-day strike on Monday and Tuesday that caused additional cancellations.

The UFO union followed that up by announcing additional strikes at Lufthansa on Wednesday and Thursday.

The four consecutive days of strikes at Europe's second-largest carrier by passenger numbers is the most serious bout of industrial action the company has had to endure for more than a decade and threatens to overshadow celebrations marking the 100th anniversary of Lufthansa's founding in 1926 as Deutsche Luft Hansa.

Lufthansa management board member Michael Niggemann said:"The renewed call for a strike by the UFO union shows in a distressing way that they are completely indifferent to the fate of our passengers and the future of Lufthansa."

But Bloomberg quoted Joachim Vazquez Burger, chairman of the UFO union, as saying strikes on the company's 100th birthday celebrations on Wednesday, which are expected to include an appearance from Chancellor Friedrich Merz, make perfect sense.

"There's hardly a more fitting place to make it clear what this is really about," Burger said. "When management, together with federal policymakers, celebrates Lufthansa's 100th anniversary, we will make it clear right there under what conditions the employer operates."

Andreas Pinheiro, president of Vereinigung Cockpit, said: "The … union feels compelled to take this step after the employer's side showed no real willingness to reach a solution in several collective bargaining disputes. Despite our deliberate decision not to take strike action over the Easter holidays, no serious offers have been made."

Lufthansa, which carried nearly 182 million passengers in 2023, has had to cancel thousands of flights because of the strikes, and is also grappling with challenges posed by fuel shortages and price rises because of the conflict in Iran. The company, which is in the midst of adopting new efficiencies, has seen its stock value fall 6.7 percent so far this year, after gains of 36 percent during 2025.

The striking pilots are seeking better pension contributions from Lufthansa while striking cabin crew want a new collective labor agreement, with redundancy assurances for workers in parts of the company that are being downsized.

The fears about downsizing layoffs follow Lufthansa deciding to focus more on short-haul flights, which tend to need smaller cabin crews.

Most of the cancellations affected flights in and out of Munich and Frankfurt, with almost 1,300 f lights canceled across the two hubs on Monday, which impacted about 50,000 passengers.

In a statement, Lufthansa said it was "working intensively to keep the impact on passengers as low as possible".