Before it opened last week British Airways, which has the exclusive use of Terminal 5, had high expectations.

The gleaming new building took 20 years to plan, £4.3billion to build and was packed with the latest technology. T5, they said, would be an “airport experience unlike any other in the world”.

How right they were. From the moment the doors opened on Thursday the flagship project turned into a shambles.

Scores of flights were cancelled and thousands of passengers were left to queue for hours.

Doors couldn’t be unlocked, the lifts were jammed, the computer system froze and the baggage handlers weren’t properly trained. It was the same story the next day and the day after that.

BA management has a lot to answer for. Heathrow is Britain’s front window; it is the first place millions of visitors here ever see.

Why did BA route so many flights through T5 on day one?

There were bound to be teething problems.

But this debacle has gone on too long and has damaged more than just BA.