Matthew Hudson led a consortium of businessmen who bought Prestwick in 1992 for less than pounds 3m and formed Prestwick Aviation Holdings. Yesterday, they sold a controlling share to newly formed Stagecoach Aviation for pounds 41m.
In a joint press conference with Brian Souter, chairman of Stagecoach - which also has bus and train operating interests - Mr Hudson said he had sought the takeover to allow further investment in the airport, turning it into a transport hub through which freight would travel between Europe and North America.
Prestwick already handles more freight than Gatwick and Heathrow combined.
Of Mr Souter, he said: "I've found a Scottish shareholder with deep pockets who shares this commitment."
He continued: "It became clear to my colleagues and I two years ago that the potential for the airport, and the need for that potential to be realised in terms of Scotland's economic benefit, meant that we would need other capital than our own."
He said he had sought backing from four international companies, but rejected each one as working with them would have meant losing control of the airport from Scotland.
He had moved on to try and find a company which was "Scottish, and likely to remain Scottish for the foreseeable future". He continued: "I did an analysis of business life in Scotland and there was one obvious candidate. It was a large public company, innovative, creative, and controlled by one family and likely to continue that way for the foreseeable future."
Viscount Younger, chairman of Prestwick Aviation Holdings, arranged a meeting between Mr Hudson and Mr Souter. Mr Souter subsequently spent a day at the airport, and then took his family on holiday with Mr Hudson's family for 10 days in Florida.
"We got on at the family level extremely well," said Mr Hudson, "and that really led to a deal. It was done on a personal, family, and Scottish basis."
Mr Souter said Stagecoach had been moving towards becoming a broadly- based transport group over the last few years. "We are excited about Prestwick, we believe that with our investment ability we can expand it on both freight and passenger levels."