The one-day strike by Ryanair pilots and cabin crew in Germany began at 3 a.m. (0100 UTC) on Wednesday and grounded 150 flights out of 400 scheduled to depart from or land at the budget carrier's 19 bases in this country.

German pilots' union Vereinigung Cockpit (VC) said shortly after the walk-out was launched that all major Ryanair bases, including Frankfurt/Hahn, Cologne/Bonn and Berlin's two airports Schönefeld and Tegel, had been affected and that "participation is good."

VC Vice-Chairman Markus Wahl said he expected the strike to become a success, and would force Ryanair back to the negotiating table. "This [strike] shows how precarious the situation at Ryanair has obviously become," he added.

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The walkout prompted the budget airline to threaten workers with job cuts in Germany if they continued industrial action, which it described as a "wildcat strike."

Ryanair's chief marketing officer Kenny Jacobs told a news conference in Frankfurt on Tuesday: "We are not making a threat. But if you have ongoing strikes, that's the economic impact."

The carrier suffered its worst ever strikes this summer, but secured a breakthrough in August when it reached deals with pilots unions in Italy and Ireland.

Chief executive remains defiant

CEO Michael O'Leary remained defiant, however, telling reporters in London:   "We are not easyJet, we will not roll over every time we are threatened with a strike,"

He described the German strikes as "somewhat unsuccessful."

 "We do not want strikes but we are willing to put up with them if it means defending our cost base and our ability to offer lower fares," he said.

O'Leary added that "we don't doubt the vigour of the German unions," butcalled a reported demand for a 42 percent pay increase "ludicrous."

Pay and conditions

Ryanair pilots and cabin crew in Germany are striking because they earn less than their counterparts at rival airlines. Another complaint is that Ryanair employs them under Irish legislation although they are based in countries other than Ireland. This would create contractual insecurity and has blocked them from access to state benefits in their country, the union said.

The Irish carrier has also come under fire, especially in Germany, for its practice of employing some pilots via third-party agencies, such as McGinley Aviation, which offer far worse conditions and pay.

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Ryanair claims, however, that it has already offered significant pay increases and steadier contracts, allowing pilots to make "up to €190,000 ($220,000) a year."

VC has countered the claim by saying that this applies to only "a handful" of pilots, and that basic starting salary at the airline was closer to €39,000 euros a year. Only the most experienced can earn around €110,000 and more depending on flight hours.

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During the labor dispute in Germany, VC has called on Ryanair to agree to mediation over pay and terms, but there has been disagreement over who the mediator should be.

Ryanair cabin crews, represented by Germany's white-collar union Verdi, are also fighting for a substantial pay increase. Their basic gross salary ranges between €800 and €1,200 a month, Verdi says, well below that of rivals such easyJet. "The wages are so low that they are insufficient to ensure a decent living standard," Verdi board member Christine Behle said.

Autumn of discontent

Last year, Ryanair decided to recognize unions in an attempt to improve relations with its pilots and ease a staffing crunch. It has been clashing with worker representatives ever since, resulting in the first-ever simultaneous walkout in five European countries.

The stoppages caused some 400 flight cancellations and travel chaos for 55,000 passengers.     

But Ryanair has also made some progress in clinching collective labor agreements, appeasing Italian pilots in August with better pay and conditions in what's become the airline's first-ever union agreement.

Irish pilots also accepted an improved pay deal 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.

But disputes with Ryanair cabin crews in Italy, Portugal, Belgium, Spain and the Netherlands are still waiting to be resolved. Unions in these countries have warned the airline should be bracing for a mass coordinated walkout in September.

Union leaders are expected to announce details of "the biggest strike action the company has ever seen" in Brussels on Thursday.

uhe,es/jh (Reuters, AFP, dpa)