Airport operators and airlines around the world are still unable to assess what financial damage may have been wrought on their businesses by last week's failed terrorist plot.
An insider at BAA, which was recently acquired by Spanish services giant Ferrovial for £10.1bn, said: "There are two areas: there's the financial cost [of the current disruption] to us and then there's the financial effects. But it is far too early at the moment to say what either of those will be. Who knows where we will be in 48 hours time?"
The market reacted sharply to the news of the foiled attacks. Some stocks were hit harder than others, with airlines and tourist companies taking the brunt of the sell-off. British Airways initially dived 5 per cent, although by Friday the carrier's shares were down just 1.5 per cent over the week.
Fears also grew about how the wider UK economy would suffer. A Grant Thornton analyst, Maurice Fitzpatrick, reportedly predicted that the delays - should they average three hours a flight - would cost the economy up to £10m per day.
But nerves started to calm as the week progressed, and the FTSE 100, after its initial slump, closed on Friday down just 3 points. And not all in the market were unsettled by the events. One analyst at a big investment bank, who asked not to be named, said BA was likely to face a hit of around £10m because of the disruption.
But, he added: "That's not a huge number in the context of things. Is this going to change travel patterns? No, not even 9/11 did that. I really don't think this is going to be a big issue for the airlines' profits and therefore for their share prices long-term."
There remain concerns, however, that airport operators could suffer a big financial blow from the security crackdown on hand luggage. Although restrictions about what passengers could take into the cabin with them were eased slightly late last week, Douglas Alexander, the Secretary of State for Transport, was reported yesterday as conceding: "I don't think we will be able to return to what we had."
Instead of the usual large bags, laptops and duty-free purchases, hand luggage was initially restricted to essential items only, such as passports and medicines. No liquids are allowed on to US flights, although more duty-free purchases were being allowed on flights to other destinations by the weekend.
Airports groups such as BAA - the owner of Heathrow, Gatwick and Stansted - garner some of their biggest revenues from retailers, so a prolonged crackdown on hand luggage would hit home hard.
Airports act as landlords, letting out retail space for high rents. This attracts a range of shops, from chemists and electrical retailers to luxury-goods companies keen to take advantage of "dwell time", when bored travellers waiting for their flights indulge in retail therapy.
"Is it significant? Yes, it's very significant," said Andrew Fitchie, an analyst at Collins Stewart.
"The whole global airport model is predicated on keeping charges for the infrastructure down by cross-subsidising from retail. That's the case with BAA and with regional airports in the UK, and it's one of the reasons low-cost carriers have been able to grow.
"It's been the cornerstone of the airport industry for the last 20 years or so."
Mr Fitchie said it was hard to put a figure on revenues garnered from retail by airports, but conceded: "We're talking not tens but hundreds of millions of pounds."Reuse content