Strike strains British Airways service, finances

But it has warned effects of the walkout will be felt throughout this week. Workers are scheduled to strike again for four days, beginning Saturday, if the dispute is not resolved.

At Heathrow’s Terminal 5, German couple Carolin and Stefan Marquardt had a seven-hour wait for their flight home to Stuttgart, after being forced to cut their vacation in India short because their original flight from Bangalore was canceled.

“I’ve been stressed by it all,’’ said Carolin Marquardt. “It’s not a very nice end to our vacation, we haven’t had any sleep.’’

“I understand both sides of the disagreement, but it’s bad for people like us,’’ she added.

The Unite union and British Airways have both claimed victory in the walkout that has caused the airline to cancel more than half its 1,950 flights normally scheduled over the period.

BA reported that nearly 98 percent of staff reported for work at Gatwick and more than half showed up at Heathrow, allowing it to reinstate a number of canceled flights.

However, Unite said that only 300 of its 2,200 cabin crew scheduled to work over the weekend turned up, and accused the airline of counting inbound crew to inflate the numbers.

BA stressed that it was legally obliged, as a listed company, to release accurate figures.

The acrimonious dispute is expected to be financially crippling for BA — analysts forecast it could cost the airline more than the $95 million that chief executive Willie Walsh is trying to save through the changes to workers’ pay and conditions.

BA said yesterday that it estimated the three-day strike would cost it around $10.6 million per day, less than the airline initially thought. It declined to forecast the cost of the next walkout, but said that its full-year profit outlook was currently unchanged.

The airline is on track for a record loss this year after reporting an operating loss of about $130 million for the first nine months, compared to a profit of $134 million a year earlier.

The walkout is also bad news for Prime Minister Gordon Brown’s Labour Party, which relies heavily on funding from labor unions, and a gift for the main opposition Conservative Party, which is leading opinion polls ahead of a general election due within weeks.

The Conservatives are seeking to evoke memories of the difficulties the Labour government had in the 1970s, culminating in the mass strikes that became known as Britain’s “winter of discontent’’ and led to the election of Margaret Thatcher in 1979.

The airline on Friday offered a compromise on a proposed pay freeze this year, offering a 3 percent raise next year and the year after and then an inflation-linked increase in 2013-14 capped at 4 percent. The other changes include a switch to part-time work for 3,000 staff and a reduction in cabin crew sizes from 15 to 14 on long-haul flights from Heathrow.