As Heathrow airport struggles to cope with twice its capacity of passengers, union bosses have warned that industrial action by overworked ground staff “cannot be ruled out”.

With the holiday rush just a fortnight away, a senior source at British Airports Authority (BAA) predicted “another summer of utter chaos” as staff shortages, heightened security measures and equipment breakdowns push Britain’s biggest airport to “meltdown”.

British Airways, the largest airline at Heathrow, with 570 aircraft movements every day, admitted that June had been “a difficult month” and that it was bracing itself for “a very busy summer”.

Stringent security checks are still causing significant delays for outbound passengers, but the biggest hold-ups this summer are likely to be in the arrivals halls. Passengers coming in to Terminal 4 are facing waits of three hours or more for bags to arrive, despite BA drafting in engineering and cargo staff to bolster undermanned baggage-handling teams.

Last week, as airport staff distributed free mineral water in the overheated baggage-reclaim hall, passengers described the delays as a disgrace. “I’ve been waiting 3½ hours for my suitcase,” said passenger Jason Lemou. “I’ll never fly through this hellhole again.”

BA ground services manager Mike Henwood blamed the delays on lack of staff and equipment. “We had a lot of scheduling problems in June, but the real problem is a shortage of staff and equipment to move luggage around,” he said. “With baggage elevators at £200,000 each, the airport’s not exactly rushing out to buy more.”

The T&G union, which represents BA’s 2,000 baggage-handlers, said staff were stretched to breaking point. “We’ve been telling BA for months that our staff are working under unsustainable pressure,” it said. “And when bad weather or security delays come along, the system cracks up. It’s management incompetence, and you have to wonder if BA’s chairman, Willie Walsh, is being given the true picture by his staff.”

Walsh said: “Heathrow operations have been very difficult in recent weeks. The airport is running at nearly double its intended capacity, and this has been made worse by extreme weather and security issues. I am delighted with the support from staff, who are working round the clock to help customers and clear the backlog of bags. The T&G’s comments do not help staff or customers in any way.”

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