Willie Walsh admitted yesterday that he was aware of problems with Heathrow's Terminal 5 before it opened — and had discussed delaying its first day.

“It was a calculated risk and one I decided to take,” the chief executive of British Airways told MPs yesterday. “You can't point the finger at anyone else.”

Despite his regret at the failings, he said that the cost of delaying BA's move to the building would have been “many times” greater than the costs incurred in the tumultuous first days.

However, Mr Walsh refused to discuss the dismissal of two senior BA executives in the aftermath of the fiasco, when hundreds of flights were cancelled and thousands of suitcases were lost because of a catastrophic failure of the computer systems.

Although Mr Walsh has held on to his job, Gary Kirkwood, BA's head of operations, and David Noyes, head of customer services, both left the company.

“I'm not prepared to talk about that,” he told MPs on the Commons Transport Select Committee. He claimed that his relationship with the management of BAA, the airport operator, was still “good”.

Mr Walsh admitted that staff were unfamiliar with the building they were working in and that the baggage handling system failed — a software filter ensured that the computer system remained in training mode.

These failings, combined with a plethora of “teething problems”, led to chaos, with hundreds of cancelled and delayed flights and a mountain of lost luggage.

His frank evidence to the committee was in marked contrast to the evidence given earlier by the head of BAA, which owns the new building.

Colin Matthews, BAA chief executive, told MPs that five weeks after the debacle his company had still to investigate “who knew what, or when” or precisely who or what was to blame, nor could he say whether or not executives had been aware of the problems that emerged before the opening of the terminal.

According to Mr Walsh, the chief problem was that staff were insufficiently familiarised with the building and the equipment that they would be operating.

A six-month training programme had been scheduled before the opening, beginning on September 17 — “when the building was supposed to have been completed”. He added: “It was not fully complete. To some extent we were showing them round a building that was different on the day it opened ... We knew this was a risk,” he said.

This combined with problems with the baggage system. More than 23,000 bags were “misconnected” — the last time the situation was reviewed, attempts were still under way to reconnect 125 of those with their owners.

Then there was the problem of a software training filter being accidentally left on. The server lacked capacity, airport jetties needed to be recalibrated by engineers, staff had problems clearing internal security and getting to their positions.

They also initially had problems getting into the company car parks and some of the lifts were not working. Though these problems could have been easily dealt with alone, together they led to chaos in the first days of Terminal 5.

He said that the decision to open on March 27 had been taken the previous summer and he thought this decision had been reviewed in the months leading up to the opening ceremony.

Before Mr Walsh gave evidence, MPs had expressed incredulity that neither the chairman nor the chief executive of BAA were able to give specific answers as to what had gone wrong.

Mr Matthews said: “I am not hiding anything. I have concluded that my first responsibility was to fix issues with passengers. I have not made time available to have an investigation on who knew what or when.”

He told MPs: “There were trials and tests of the baggage system. With the benefit of hindsight, we were not successful.”

Mr Matthews only formally joined the company on April 1 though he was present at the opening as he sought to get to grips with his new role.

Sir Nigel Rudd, BAA chairman, said that Mr Matthews had replaced the outgoing chief executive because he possessed greater operational experience. He told the committee that the problems at Terminal 5 constituted the greatest failing of his career.

“This is clearly a huge embarrassment to me, the company and the board,” he said. “Nothing can take away that sense of failure. We all worked extremely hard to make this work. We all believed, genuinely, that this was going to be a great opening.”

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