First the good news: the Tony Wibble Tour is going ahead. Eighteen lads from Maidstone, Kent, heading off for a raucous stag weekend in Barcelona appeared to be among the lucky ones at Gatwick airport this morning.

But thousands of others faced cancellations or impossible delays heading off on their summer breaks from London's second airport after the foiling of a terrorist plot put Britain on its highest level of security alert.

For the first time, passengers were told that they could take no hand baggage aboard their flights, except for the bare essentials such as a passport, boarding pass and wallet.

Staff in yellow waistcoats were handing out large transparent plastic bags to make sure no-one cheated. Security checks at departure gates and boarding gates were stringent.

Stuart Edmonds, a 25-year-old heating engineer, did without the plastic bag, holding his passport and boarding pass in his hand as he queued up to go airside.

His easyJet flight for a stag weekend in Spain had been due to leave at 6.55am. Three hours later, he was finally through check-out and waiting for the last 15 of his mates to join him.

"It's not been so bad," he said. "We should be there by two or three this afternoon."

They were the lucky ones. Other easyJet passengers were told that if they were not booked on the first wave of short-haul departures this morning - those due to leave before 8.15am - there were no guarantees they would ever get away.

Tactfully, they were advised that they might want to go home and rebook for another day at no extra cost. "I could do that," said one woman heading for Majorca, "but Sod's Law would mean my flight would be next out."

So an easyJet manager came onto the check-in hall at Gatwick's South Terminal and appealed at the top of his voice for passengers on later flights to go away and come back later. "There is no point for any passenger to be on this check-in concourse if their flight is leaving after 8.15," he shouted.

"You are not going anywhere. So clear the concourse, go for a coffee."

That performance earned him a round of applause, although it was not clear why people should cheer when they have just been told that their holiday plans were up the spout.

By mid-morning, tempers had finally started fraying in the South Terminal, which is dominated by the budget and charter airlines. The doors into the check-in area were blocked and large, snaking queues formed all around. In the chaos, it was hard to tell who was first in line.

For the most part, however, the atmosphere was surprisingly cheerful. Passengers shared snippets of news about the foiled plot, picked up in mobile phone calls to their friends; there was no sign of any panic.

Dean and Sharon Harrison, on their way to a two-week holiday in the Dominican Republic, took just 15 minutes to reach Gatwick from their home in Dorking, Surrey. Their main worry appeared to be how to keep their three daughters - Gemma, Alex and Georgina - occupied on the nine-hour flight without their books, games or headphones.

"We've had to pack all our books, MP3 players, everything," said Sharon. "I'm re-reading the latest Harry Potter and had hoped to finish it on the plane. Now I'll have to do so on the beach."

"People are just getting on with it," said Dean. "I'd rather spend an extra hour here than have any trouble."

Karen Leitch, a 28-year-old teacher from Belfast, was waiting for a flight home after a summer break in Egypt and London, but said that her incoming flight was late arriving. But she said that she'd heard no complaints from passengers. "I have to say I'm impressed. They've been queueing, just getting on with it.

"There was a thing on the news yesterday saying that British people don't like queueing any more. That's not right, from what I can see."

In the North Terminal, dominated by British Airways and the long-haul airlines, the queues were much smaller. Flights appeared to be getting away with only an hour or two of delay and, unlike Heathrow, most incoming flights were making it in.

"It's not so bad over here because we get a lot of business travellers. They're much more experienced," said one BA security guard. "But you'd be surprised how many women try to insist that their make-up is an essential item."

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