Reaction:Dr Tony Ryan's passing brought a sad but warm reaction from business leaders and politicians alike, who paid tribute to his vision and skill in establishing two businesses - GPA and Ryanair - that became world leaders in their fields.
Ryanair chief executive Michael O'Leary, who worked as Dr Ryan's personal assistant before taking the reins at Ryanair, said his former boss was one of the 20th century's greatest Irishmen.
"His many achievements in business education, sport, the arts and heritage preservation leave an astonishing legacy to an extraordinary man," Mr O'Leary said. "It was a privilege to work for him and to learn from him."
These sentiments were echoed by Ryanair's chairman, David Bonderman. "He possessed an extraordinary vision," Mr Bonderman said. "Whether it was in airline investments in Asia, vineyards in Europe or bloodstock in the US, he brought a tremendous sense of style, charm and good humour to all of his business and personal relationships."
Taoiseach Bertie Ahern described Dr Ryan's contribution to the development of aviation in Ireland as "immense".
"Through Guinness Peat Aviation, he placed Ireland centre stage in the global aviation business," Mr Ahern said.
"He also recognised the enormous potential of increased competition in the market for air services to transform the European economy.
"The establishment of Ryanair and its subsequent rise to become one of the leading carriers in Europe is one of the greatest Irish economic success stories and will be rightly regarded as perhaps his greatest legacy."
Tributes poured in from former colleagues and fellow entrepreneurs. Speaking on RTÉ television, businessman Peter Sutherland described Dr Ryan as a man of "vision" and said he bounced back from GPA's failed flotation in 1992 to help Ryanair to success.
"He picked himself up and created Ryanair out of a sense of national commitment rather than anything else," Mr Sutherland said.
Jim King, a former chief executive of GPA Leasing, worked with Dr Ryan for 15 years in the leasing and finance business.
Mr King described Dr Ryan as a "wonderful judge of people", highlighting the fact that Mr O'Leary and Denis O'Brien, two of Ireland's most successful businessmen, were his proteges.
"Two years before Michael O'Leary became prominent, Tony told me that he had found a young man who would go on to become the greatest airline manager of his generation," Mr King said.
Sir Anthony O'Reilly, who controls Independent News and Media and was a contemporary of Dr Ryan's, described him as "immensely hard-working, talented, witty and, at times, a hard task master".
"He changed the skies of Europe, not just for the Irish people, but indeed for all Europeans," Sir Anthony added. "That will be his epitaph."
His contribution to the midwest was also recognised. Seán Donlon, chancellor of the University of Limerick and a former diplomat turned GPA employee, hailed his contribution to the region.
"He supported the development of the University of Limerick, particularly in the 1970s and 1980s at a time when there were few people in the area in a position to do so."
Padraig Ó Ceidigh, chairman of Aer Arann, said Mr Ryan's achievements in aviation were an inspiration to him in growing his airline from merely providing services to the Aran Islands into an international carrier.
"He offered me advice about doing business," Mr Ó Ceidigh recalls. "He was passionate about Irish aviation and took an interest in me from that perspective. He was an inspiration to all of us in the industry."
Mr Ó Ceidigh said Dr Ryan contacted him two months ago suggesting that they meet, but had to cancel the appointment due to his illness. "I think he had a business idea that he wanted to put to me but, sadly, I'll never know."