Stirct new check-in requirements at Heathrow's Terminal 5 could lead to thousands of passengers missing flights when it opens in March.

Travellers flying from T5 will be required to pass through security at least 35 minutes before take-off or else they will be denied access to go through to boarding gates.

Machines will tell passengers that they are too late even if they are a few seconds behind the cut-off, and even if airport queues or public transport delayed them. Aviation experts predict a summer of complications as flyers get used to the changes, which will include becoming familiar with the check-in computers that replace traditional check-in desks and “fast bag-drop” booths. Another change will be a requirement to have a fingerprint scan at the security gate for domestic flights.

The system, and the cut-off times, apply to economy and business travellers alike - and will probably hit last-minute celebrity “don't you know who am” antics at the gates.

Jamie Bowden, a travel consultant who used to manage customer service at Heathrow's T1 and T4, told Times Travel: “In time I think things will be OK, but this summer could be quite challenging.”

Gary Noakes, an airline writer, said: “It's going to create aggro. People are going to have to learn to turn up earlier.”

A spokeswoman for BA, the only airline using T5, said: “It's hard to speculate what might happen.”

Details: www.terminal5.ba.com

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