"We all have a responsibility to make sure that internal industrial relations matters are dealt with in such a way that doesn't hurt passengers, " he added later when asked to explain why he did not hold Siptu responsible for going ahead with industrial action despite a 250m sweetener for employees that, if anything, is considered too generous by many observers.

"My job is to make sure that whatever IPO negotiations might be going on in the background don't disrupt the travelling public, " Mannion said.

The airline chief executive said he will buy Aer Lingus shares when they are offered to the public.

"I will buy a few shares but in the overall scheme of things it will be very insignificant I'm sure."

Aer Lingus management will not receive share options as a part of the flotation, the airline confirmed.

Mannion rejected any suggestion that Irish retail investors might be too gunshy after the controversial Eircom privatisation to buy Aer Lingus shares, which will be offered to the public in minimum tranches of 10,000.

"Aer Lingus is a different value proposition to Eircom, " he said. "The Eircom transaction happened a number of years ago. The market is different for investors, institutional and retail."

Mannion spoke at a UCD Smurfit School of Business marketing development programme business breakfast at Dublin's Conrad Hotel. His presentation, "Aer Lingus . . .The Future", had been scheduled well in advance.

The Aer Lingus chief executive ruled out the possibility that the airline would be predator or prey as the consolidation of European flag carriers looks increasingly likely following the merger of Air France and KLM, cleared last week by a European court. "Our focus is growth here in Ireland, growing the Dublin hub, " he said.

"That's the task, and it was the same in my previous life at Emirates. Emirates had the opportunity for investing in other airlines but its focus is Dubai as a hub. Our focus is developing Dublin."

The vision of Dublin as a hub airport drew a question from Sean Murphy of Chambers Ireland about the airport's expansion requirements in that event.

Up to 50 million passengers per year could travel through Dublin Airport if it were a hub, requiring not only a third airport terminal but additional runway capacity.

"This number of passengers isn't a crazy statistic if Dublin becomes a hub, " he said later. "The key driver is congestion over European skies and a physical issue with jets flying around for 30 minutes or more while they wait for a slot to land. It's just uneconomic for airlines and a key opportunity for Dublin as a hub.

"The planning for a third terminal should start now, and an Environmental Impact Study carried out so the development can be ready to go. Very rapidly, on current trends, we're going to need terminal three."