Thousands of Ryanair passengers faced travel disruption Wednesday as German pilots and cabin crew walked off the job, in the latest flare-up of a bitter Europe-wide battle for better pay and conditions.
The Irish budget carrier said it was cancelling 150 out of 400 scheduled flights to and from Germany because of the walkout, which it slammed as "unacceptable" and "unnecessary".
It also said it may have to close some bases and slash jobs if the stoppages drag on.
Germany's Cockpit pilots' federation and the Verdi service workers' union called the 24-hour strike, which started at 03:00 am (0100 GMT), after they said talks with Ryanair management were deadlocked.
The strike comes as Ryanair is already bracing for a mass coordinated walkout by cabin crew in Belgium, Italy, the Netherlands, Portugal and Spain.
Union leaders are expected to announce details of the stoppage in Brussels on Thursday.
They have vowed to stage "the biggest strike action the company has ever seen".
Ryanair has been clashing with worker representatives ever since it took the unprecedented step last year to start recognising trade unions in a bid to avert widespread Christmas strikes.
Last month, Ryanair pilots in five European countries including Germany held their first-ever simultaneous walkout, causing some 400 flight cancellations and travel chaos for 55,000 passengers.
- Job threats -
Ryanair has however made some progress in clinching collective labour agreements since then.
The 33-year-old company managed to strike a deal with Italian pilots over working conditions in late August, its first-ever union agreement.
In Ireland, pilots voted to accept an agreement on improved working conditions last week.
The breakthrough prompted Ryanair to back down from an earlier threat that it would move several aircraft and 300 jobs from Ireland to Poland.
Germany's Cockpit and Verdi unions, which represent some 400 Germany-based Ryanair pilots and 1,000 flight personnel, condemned the airline's attempt to squeeze them with a similar threat.
"This is how Ryanair deals with its employees: putting pressure on them, scaring them and threatening job losses," Cockpit's vice president Markus Wahl told AFP.
Ryanair's chief marketing officer Kenny Jacobs said on Tuesday that further strikes would damage Ryanair's business in Germany and "lead to base cuts and job cuts".
"We are not making a threat," he told a Frankfurt press conference.
"If you have ongoing strikes, that's the economic impact."
- '190,000 euros a year' -
The no-frills airline boasts lower costs per passenger than its competitors and is eyeing profits of around 1.25 billion euros ($1.45 billion) this year.
But staff have long complained that they earn less than counterparts at rival airlines.
Another key gripe of workers based in countries other than Ireland is the fact that Ryanair employs them under Irish legislation.
They say this creates huge insecurity for them, blocking their access to state benefits in their country.
Unions also want the airline to give contractors the same work conditions as staff employees.
Ryanair counters that it has already offered significant pay increases and steadier contracts.
It said German pilots can make "up to 190,000 euros a year".
But Cockpit's Wahl said that only applies to "a handful" of people.
The basic starting salary for Ryanair pilots is closer to 39,000 euros a year, he said, while the most experienced pilots can take home around 110,000 euros a year in fixed pay. That can then be topped up depending on flight hours.
Wahl said pilots were fighting for more pay overall, and specifically a higher fixed-rate salary.
The Verdi union said Ryanair cabin crew earn a basic gross salary of 800 to 1,200 euros a month on average, far below what rival EasyJet pays.
"The wages are so low that they are insufficient to ensure a decent living standard," Verdi board member Christine Behle said.