Yet much of his career is defined by his GPA experience.

The rise and near fall of GPA is perhaps the most remarkable Irish business story of them all. A company formed in 1975, which made a profit of just �137 in its first year, came by April 1992 to earn $268m in profits. Within a year, it was almost gone and when the giant GE Capital sanctioned a rescue of the company, the terms were so onerous that Ryan accused its boss Jack Welch of virtual rape. "What do you expect?" replied Welch caustically, "when you're walking around with no clothes on."

Among the many bitter ironies for Ryan was that he retired from GPA a year before the failed IPO on the world stock markets. He then had to return in a desperate effort to stave off collapse.

"I would want to be very cold-blooded not to still regret what happened. This was a company that had been profitable every year in its existence, an Irish company on the world stage that had been profitable for 17 years. And it was put out of business in June 1992, despite having the best people ever assembled in the aircraft business, all because some blundering investment bankers didn't understand the market. They weren't able to organise the stock market offering they had promised and should have told us to stop it far earlier before everyone's confidence was damaged. I felt extreme anger that that was allowed to happen, especially as everything we had planned and forecast for the company at the time has since happened in spades. We estimated that the world needed about 20% of its aircraft on lease but the bankers challenged this as too ambitious. Today 50% of the industry is on lease and climbing. Our analysis was correct."

Yet from the date the IPO was pulled, everyone lost confidence in GPA, and its credit lines dried up. It was a dramatic example of how sentiment can change so quickly to such negative effect. In the most difficult circumstances, Ryan led his GPA team to conclude an equity partnership with GE Capital.

"We continued to pay our bills and paid a $1bn restructuring charge. The $11bn of debt was all paid down. None of our lenders lost a cent, " he said. "It was a sad time and we didn't deserve to go out of business but that's life."

The investment bankers that Ryan has blamed never apologised for their failure.

"They never even replied to letters seeking an explanation, " said Ryan. "Afterwards, there was a terrible temptation for retribution. . . But I felt it was more important to be calm and to restructure rather than getting into haggling over the causes of GPA going out of business."

He never sued because he was not a party to contracts.

Nor did GPA, as it concentrated on reorganising itself.

Good came out of it, however.

"We held onto two major industries in Shannon which it was forecast would collapse because we were gone . . . Shannon Aerospace and Shannon Turbine Technologies, which now employ 1,200 people and are doing exceptionally well.

There have been a lot of very positive spin-offs. The people we had at GPA have become like a galaxy exploding. They're all stars somewhere else now.

I was at an aircraft finance conference a couple of years ago and of the 38 chief executives there, 36 were from GPA."

Fortunately for Ryan, he also had Ryanair. Although he had been pivotal in setting up the company in 1986, it had all been done through his sons for legal reasons. It was to prove a difficult and costly investment at first, with the company losing over �20m in its first five years.

"People can't believe now that we were forced to operate propeller aircraft on the Dublin route. But the department of transport defended the Aer Lingus monopoly to the hilt, to the detriment of the consumer, who had to pay massive fares, and ultimately that damaged Aer Lingus too, " he said.

"In 1991, we restructured the management of Ryanair and the modus operandi of the company. Instead of trying to compete on service and other areas, Michael O'Leary decided to follow a very basic line of cutting costs to get a more efficient organisation and offer lower fares and try to crack the monopoly we had been trying to break for six years. After some time, we succeeded and that was the first breakdown of a monopoly in Ireland and it was probably the biggest one.

Not only was it broken down, it was obliterated, " he said.

Ryan pulls out a piece of paper with airline valuations written on it. "Ryanair is worth more than KLM, SAS and Aer Lingus put together, " he says proudly. "Michael O'Leary is the best chief executive I've ever worked with. He's handson, leads from the front, he knows how to run a business, and he drives costs down with a passion few chief executives can match. He is not proud, he has ambitions for the airline and as an accountant he runs it very prudently."

Ryan believes Ryanair's success has had massive social import in the country.

"Going to London or the UK was regarded as part of the emigration process. . . Once Ryanair started operating, people started going out of the country on a Monday and coming home on a Friday. I'm not claiming all of the credit but the word 'emigration' isn't used any more."

He said the concept [of the centre for entrepreneurship he helped found] developed from a conversation between Ed Walsh, former head of the University of Limerick, and Ryan's three sons, as to what caused the economic boom.

"Nobody knows how long its going to stay and nobody knows where it's going to go, " said Ryan. "Everybody wants to be an entrepreneur. They turn up with bankers and advisers who kill them before they start, even if they have a good idea. They have no management training, " he said.

Ryan demurs at the suggestion that he appears more relaxed now than in the past.

"I always thought I was relaxed. You are only relaxed in your mind, not in other people's perception of you, " he said. "I have always enjoyed myself, whether I was working or not. It is the discipline of running a company and having to be there every day that is difficult. I miss the camaraderie of working with an extraordinary team of talented people.

The interchange of ideas and information is stimulating. I still work with a lot of good people but not in the same type of office environment."

While he is respected by his former GPA colleagues, he is perhaps not held in deep affection because of the infamous Monday morning meetings everyone had to attend at Shannon, no matter where in the world they had been the previous week. Ryan was known as the Seagull, because he would swoop in, drop on everyone and fly off again.

"That was a time when I had a whole group of young people who were given exceptional responsibility, such as buying $30m aircraft. We applied discipline in time-keeping, presence, dress and punctuality and all the other good things and I felt that as these meetings were the only occasion we met in a week, there was no room for ambiguity. The meetings lasted exactly for an hour.

The work for the week was clearly defined and specific. It wasn't a time for coffee and a chat. If I terrified them, they're still around."

Is his drive still there?

"There comes a certain time when you have to pass the baton. I have three boys who are interested in the things I'm interested in. We often do things together but they run the businesses now. What do you do when you're 65? Buy a new set of clubs, a fishing rod, take up jogging, lie on the beach all day? Or do you continue to do the things you enjoy doing? My father used to have a great expression, 'it is better to wear away than rust away'."

Tony Ryan, 71, died last Wednesday at his home in Lyons Demesne, at Celbridge, Co Kildare, after an 18-month battle with pancreatic cancer.