ALL HAIL Open Skies, the deal to liberalise air travel between Europe and the US.

It takes effect at the end of this month, and has led to US-based airlines paying sky-high prices to gain prized slots at Heathrow, boosting the value of Aer Lingus's landing privileges there.

Just this week it emerged that Newark-based Continental Airlines recently paid a record $209 million for four pairs of slots at Heathrow, which it bought from GB Airways, Air France and Alitalia. It plans to go transatlantic from Heathrow for the first time.

Continental paid the equivalent of €34 million for a pair of slots (take-off and landing). With Aer Lingus owning 23 pairs, the Irish airline is sitting on an asset that is now potentially worth a sky-high €782 million. That's some 60 per cent of Aer Lingus's current market value of €1.3 billion.

Last summer Goodbody Stockbrokers estimated the Aer Lingus slots were worth €380 million. It should comfort investors who might be fretting about the impact that the $100-plus price of a barrel of oil might have on the industry.

Of course, Aer Lingus boss Dermot Mannion might never realise this potential bounty. The Government's 25 per cent stake gives it a block on any sale of the Heathrow slots.

But who's to say it won't lease out some slots or persuade the Government to allow it sell a couple of them down the road?

If it can switch slots from Shannon to Belfast in the interest of its commercial well-being then anything is possible.