London Briefing/Fiona Walsh:It was, by all accounts, an ugly scene at Heathrow last Saturday evening: raised voices, angry words and the threat of retaliation hanging heavy in the air. But it wasn't the weary passengers who finally flipped.

It was an extraordinary confrontation between British Airways boss Willie Walsh and Tony Douglas, the British Airports Authority Heathrow chief executive.

In what was said to have been a highly-charged meeting, the two men had a heated exchange at BA's Heathrow headquarters as the chaos in Britain's airports threatened to spiral out of control.

BAA, now owned by the Spanish construction firm Ferrovial, is in charge of running Heathrow. But its handling of the airport since the foiling of the alleged threatened terrorist attacks last week has been fiercely criticised by the airlines.

Former Aer Lingus boss Walsh and fellow Irishman Michael O'Leary of Ryanair have been most vocal in their complaints, accusing BAA of failing to deal with the crisis effectively.

In typically robust fashion, O'Leary said BAA's "heavy-handed" measures had enabled the terrorists to achieve many of their objectives.

In turn, BAA made an unprecedented threat to ban any airline from using Britain's major airport if it did not stick to the rules.

There is a huge amount at stake for BA, not least its reputation among passengers, many of whom are unaware that BAA calls the tune at Heathrow and blame the airlines for the delays.

And financially, the cost is huge. Latest industry estimates say the cancelled flights - still running at the rate of one in five at Heathrow - have already cost the airline industry as much as £250 million (€370 million) in lost revenue. For BA, the losses at Heathrow and Gatwick are put at £50 million so far, a figure that exceeds the cost of last year's damaging Gate Gourmet catering dispute, which also did little for the airline's reputation.

The cost to Virgin is estimated at £15 million and the bill for Ryanair and Easyjet is put at around £10 million apiece. No wonder tempers are frayed.

While the scene at Britain's airports remains confused almost a week after the terror threat emerged, one thing is now clear, not only to the airlines and the airport authority, but also to long-suffering passengers: travelling by air is unlikely to be the same ever again.

The ease with which liquid terrorist materials can be taken on board means some permanent restrictions on hand luggage are inevitable: inconvenient for passengers, but another financial blow to the airlines. Particularly affected will be Ryanair and other low-cost carriers who have a policy of persuading travellers to fly with hand luggage only by charging for check-in bags.

But the new terror threat and the need for additional security measures will put increased pressure on costs for all involved in the airline industry - and, in the long run, that includes the passengers.

Meanwhile, London retailers and the capital's tourist attractions fear another blow to business as overseas visitors simply decide to stay at home.

Although numbers have never really recovered from 9/11 five years ago, American tourists remain by far the most important group of overseas visitors to the UK, with spending estimated at over £2 billion a year.

Last year's tube and bus attacks in London did not help and the scenes of chaos from Heathrow beamed around the world in recent days will set back the recovery even further.

Aston Villa shares face climb to top table slot

Jaded Aston Villa fans have been known to joke that the only way their team will reach the top of the premiership league is if the clubs are rearranged in alphabetical order.

So news that American billionaire Randy Lerner has agreed to buy the Midlands-based club for £63 million has raised hopes of better things to come on the back of a "Chelski-style" spending spree.

It's the second piece of good news for supporters in recent weeks, following the arrival of the highly regarded Martin O'Neill as manager at the start of the month.

The new manager has, apparently, been promised "appropriate" transfer funds from the new owner.

Lerner joins an elite list of wealthy foreign sports fans to have set aside the normal rules of economic return to invest in the bottomless pit known as a football club.

Others include American Malcolm Glazer, owner of the Tampa Bay Buccaneers, who paid almost £800 million for Manchester United last year, and Russian Roman Abramovich, who has spent a fortune on players since moving in at Chelsea.

The Egyptian-born Mohammed Fayed bought Fulham in 1997 and the Irish have also been active, with former player Niall Quinn leading a consortium for Sunderland.

The Aston Villa deal has been agreed by 36 per cent shareholder Doug Ellis, widely known as "Deadly Doug" and generally reviled by Villa fans for failing to stump up more of his millions to support the struggling team.

But the club's performance on the stock market has been as poor as the team's performance on the pitch. When Aston Villa floated on the London market in 1997, the shares were valued at £11. Yesterday's takeover terms value them at just £5.47.

• Fiona Walsh writes for the Guardian newspaper in London