LONDON (AP) — Airline passengers arriving in Britain escaped chaos early yesterday despite dire predictions of long waits, as border staff joined teachers, hospital workers and weather forecasters in the country’s largest strike in decades.

The one-day strike has been called in protest at the government’s plan to make public sector pensions less generous in the years ahead. The pension reforms are part of a package of austerity measures designed to get a grip on the country’s high borrowing levels.

London’s Heathrow Airport and scores of airlines had warned that international travelers could be held in lines for up to 12 hours at immigration halls as a result of staff shortages. But airport managers said flights arriving early Wednesday from the United States, Asia and Europe were largely unaffected, in part because of contingency plans which saw bureaucrats drafted in to staff border desks.

“Immigration queues are currently at normal levels,” Heathrow’s operator BAA said in a statement. “However, there still remains a possibility of delays for arriving passengers later in the day.”

Labor unions said as many as 2 million public sector staff were expected to join the strike, called to oppose government demands that they work longer before receiving a public pension and contribute more money each month.