While Ryanair's bid to snap up Aer Lingus is certainly unexpected, it does not herald the demise of traditional carriers.

Aviation expert and former Ryanair executive Conor McCarthy, who owns a stake in successful Malaysia-based low-cost carrier AirAsia and who has also taken a small stake in Mexican start-up Aerobus, being heavily backed by Tony Ryan, thinks that no-frills airlines are experiencing "inexorable growth", but that it remains focused on short-haul traffic.

Some low-cost carriers are branching out into the longhaul market. Among them is Qantas-owned Jetstar, an operation headed by former Aer Lingus employee Alan Joyce. The Australian carrier will commence flights to Hawaii at the end of December and introductory fares have already sold out.

McCarthy is unsure that such models will work, but cites the availability of lowerpaid pilots in the Asian region as one factor that makes such a move potentially workable.

Joyce, who turned down the Aer Lingus top job last year, was briefly in Ireland last week.

He agreed that Australia presented a different opportunity to Europe or the US due to its effective isolation and size, and he believes the long-haul model will work.

"We're carrying an average of between 600,000 and 700,000 passengers a month domestically and when we began selling seats to and from Hawaii we had a huge response, " he said. "We sold 80,000 seats and the website melted down. We took in twice the amount of daily revenue in our history on the day we started selling longhaul seats."

While the model may work for the Antipodean player, will a tie up between Ryanair and Aer Lingus make sense?

"My first reaction when it was announced was that it's a really smart move. I don't see any way Ryanair can lose with this, " said Joyce.

Others aren't sure it will ever happen.

"This takeover is opposed by some serious players who effectively are a bottomless pit when it comes to finance and the national interest, " suggests Malcolm Ginsberg, editor of Air and Business Travel News, who thinks the move is a "non-starter".

"Perhaps Michael should have made bids for Olympic Airways and Alitalia, both basket cases, going nowhere and protected. Dublin also has many friends in Brussels who can make the buyout virtually impossible, " he added.

Alitalia may be a basket case, but it's pretty much certain that any third party that offered to buy it would also be of a similar mind. To turn around such an ailing airline would be a daunting prospect. Aer Lingus, on the other hand, is financially fit and further efficiencies could be squeezed from it to improve margins.

Ginsberg does not believe that any Ryanair buyout of Aer Lingus will introduce radically new thinking in aviation.

"A lot of middle-level managers in Europe will travel with low-cost carriers, for example, but there's still a requirement for a quality product, " he said, Look west to Ryanair's inspiration, and perhaps some of O'Leary's rationale becomes clearer.

Southwest Airlines, whose founder's brain O'Leary cherry-picked before revamping Ryanair into a low-cost carrier, has already teamed up with an other operator to extend its offering. Southwest paid $117m in 2004 for a 27% stake in then financially struggling ATA and access to some of its slots at Chicago's Midway airport. More important, the deepening alliance between the two operators allows Southwest to sell its customers tickets to destinations such as Hawaii.

ATA also serves airports such as New York's La Guardia, which Southwest had steered clear of because of congestion concerns.

So far the marriage is working. The two airlines have also developed a formal codeshare agreement. Could Ryanair develop a low-cost transatlantic alliance that would include Aer Lingus and Southwest?

Respected New York-based aviation analyst Bob Mann thinks that's a long way off, but he says low-cost alliances will happen.

"There are already discussions going on, " he says.

"However, low-cost airlines tend to sell exclusively on proprietary booking systems, so getting those systems to talk to one another when they weren't ever designed to do that is a hurdle. But technology changes pretty fast these days and it's a matter of lowcost operators having strategic discussions which will result in someone deciding to go forward and figuring out a timeline within which they can integrate those systems."