Mr John McDonnell has a schoolboy's fascination for aircraft. The former air corps pilot beams with pleasure as he talks about the thrill of flying Boeing 747s and DC 10s. But in recent years, Mr McDonnell has traded in his flying suit for the pinstripe variety. Now, as chief executive of the Irish Aviation Authority - the semi-state regulatory body responsible for air traffic control and safety of the skies - he insists he has few regrets.

The authority has an enviable record in terms of safety and cost efficiency, says Mr McDonnell. "But I don't underestimate the task the authority has: you are what you bring to the party," he says.

Year-on-year increases in air traffic are posing significant challenges to aviation authorities worldwide, according to Mr McDonnell. En route traffic in Irish airspace grew by 11 per cent last year, representing 237,100 flights and the Republic currently handles more than 80 per cent of all transatlantic traffic between Europe and North America.

Increased traffic boosts revenue for the authority which charges carriers for using Irish airspace. Last year the authority had turnover of some €76 million (£60 million) and realised a profit of more than €7 million.

But it is "value-for-money" rather than overall revenue which differentiates the authority from many other international authorities, says Mr McDonnell. "We have the lowest unit rates for en route charges within Europe," he says.

Statistics from Eurocontrol back up this claim and in 1998 the authority won the coveted Productivity Eagle Award for the best air navigation provider in the world. This was especially pleasing because it is recognition gained from the carriers who use our service, says Mr McDonnell.

But things weren't always so positive. When Mr McDonnell took over as chief executive in 1994 there were considerable grievances among staff caused in part by a recruitment embargo within the civil service, he says.

A necessary reorganisation to bring in modern equipment and best practice methodology at a time when the Republic's finances were in a parlous state, was traumatic, according to Mr McDonnell. But the grievances were legitimate and required action, he says.

The introduction of an integrated national system and the construction of a new centre at Dublin Airport were steps in the right direction, says Mr McDonnell. And the authority has continued to expand its capital expenditure and work will shortly finish on a new air traffic control centre in Shannon.

Effective leadership was important to push through such changes, says Mr McDonnell, who describes his style as that of a "ringmaster".

"I'm happy to have a team around me and if they are worried about anything they can come to me. I prefer an open and transparent leadership style. But if decisions have to be taken I'm quite happy to do that."

Building the right team and creating a genuine team spirit within the organisation is important, says Mr McDonnell.

This partnership approach between management and staff could be perceived as an element which may enable some form of public private partnership approach to future regulation of the skies. Such an approach is favoured by the British government.

"It is not on the Government agenda at the moment," says Mr McDonnell. "But on a personal level I think it could lead to greater efficiencies and more commercial opportunities as aviation becomes increasingly global."

At 60 years of age, Mr McDonnell is clear he won't be in the job in 10 years when such a prospect could become a reality.

And he intends to spend his retirement pursuing a variety of hobbies. A keen yachtsman, Mr McDonnell, enjoys crewing whether it is in Dublin Bay or the scenic west coast of Ireland. He is also keen to get airborne again after several years of pen pushing.

Although a former rugby player with Terenure, Mr McDonnell, is one of the few who have crossed the sporting divide and is a keen follower of hurling. However, before he goes, Mr McDonnell, is keen to leave an indelible mark on the organisation. "I want to address the strategic issues which we are facing," he says. "I'd like to set the authority up to be able to cope with institutional, technical and globalisation changes."

The EU open skies policy looms large on the horizon. The European Commission has initiated discussions on a "Single Sky for Europe" which will focus on resolving the traffic congestion in European airspace.

Traffic congestion manifested itself in "pretty bad" delays for Irish and European passengers last year, according to Mr McDonnell. But most of the delays in the Republic originate while aircraft are waiting to land or depart from other European airports, he says.

"Many states have not invested in people or equipment and implementation plans take up to three years to complete."

They are also a symptom of the huge increase in air traffic - which is growing by 5 per cent per year, says Mr McDonnell. "Can you imagine any road system or sealanes which could accommodate that kind of growth?"

Despite four "air prox" incidents (near misses) in Irish air space last year, Mr McDonnell is confident the system can cope with the additional traffic. "If you get any system overloading the decision has to be made when not to let any more aircraft into the airspace."

But taking tough decisions is not something Mr McDonnell has shirked during his career. In the 1970s he served with the Irish army in a peacekeeping role in Cyprus and the Sinai. "It was a very difficult period especially in the Sinai. We had to survive on iron rations for the first six weeks in a very hostile environment."

Despite coming under fire and negotiating minefields in the extremely tense Middle East, the Irish division Mr McDonnell served with never lost a soldier. "It made me recognise that Irish soldiers were as good as any other army in the world and it gave me a great confidence in my own ability," he says.

The aviation authority will have to remain among the best to survive the rapid consolidation that is likely to occur in worldwide air travel over the next few decades. Within five or 10 years a large chunk of the airspace which the authority controls and gains substantial revenue from - Shanwick Oceanic - is likely to be consolidated with other airspaces over the Atlantic, according to Mr McDonnell.

"The UK, Portugal, Iceland and Canada will all be competing to manage the skies over the Atlantic," he says.

With up to 80 per cent of the authority revenue coming from this source it is essential that the authority maintains its efficiency to compete for this area, says McDonnell. This is one dogfight Mr McDonnell is determined to win.