By 1pm today, the carrier had called off 20 services to a number of European cities as well as internal flights.

It later suspended baggage check-in but has now called off 34 flights from the £4.5m terminal.

Today was supposed to be the triumphan launch of the new terminal but it descended into chaos from early morning as some passengers were left waiting hours for baggage collection and suffering what BA described as a variety of other 'teething problems'.

It is understood baggage handlers were unable to log into the new system, which is designed to process up to 12,000 bags an hour, as computers failed to recognise staff identities.

Many passengers gave up waiting after a two hour delay in their baggage delivery.

And to add to the problems, computer difficulties also meant here was a problem with bags on departing flights, with three leaving without luggage on board.

British Airways, which has exclusive use of the new terminal, issued a statement this afternoon admitting it had had "a few minor problems" and added this was not unexpected following a complex move of most of the airline's operations to T5 from other parts of Heathrow.

Among the problems identified were:

Car park provision

Delays in staff security screening

Problems with staff familiarisation with the terminal.

Travellers also complained about the poor road signs to the airport and the fact some escalators were not working.

Following the earlier cancellation of 20 services, a large queue of people wound back from the cancellation flights desk as people lined up to try to get away on other flights or get refunds.

To add to the difficulties the luggage belt in one part of the departure lounge failed and passengers were moved further down to a workable area.

Kate Adamson, 39, arriving from Frankfurt with her daughter Olivia, five, to visit her parents in Maidenhead, Berkshire, gave up waiting for her luggage after it had still not appeared after 90 minutes.

Mrs Adamson said: "I am furious. Staff have been really surly. There were no announcements and just one BA woman on duty who was saying there was a technical problem.

"I've given up. They can send my luggage on to me."

Equally unimpressed were Mark Geoghegan, 34, and his friend Lisa Evans, 27, from Tottenham, north London, who had a two hour 15 minute wait for bags following a flight from Los Angeles.

Mr Geoghegan said: "Nobody really seemed to know what was going on. Staff seemed as much in the dark as we were.

"They still seem to be working on the terminal. We could hear drills going."

The couple had been on a two-month trip around the world which included stops in Australia and New Zealand. Mr Geoghegan added: "We had nine flights on our trip and today's was easily the worst."