Back home in Greece there was national service to be done, in the air force naturally. But by this time he had realised that the best opportunities came to those who kept their feet on the ground - not their heads in the clouds. He also began to think seriously about business. Commissioned as an administrative officer, he eventually became adjutant to the commander of the tactical air force, based at Larisa in central Greece, and made a point of being around whenever any representatives of civil suppliers appeared at headquarters to make presentations. "I came to realise the hugeness of the market," he recalls. "I could see that this was where my future lay."
Once out of uniform and into HAI, Mendoros made rapid progress, mainly up the quality assurance ladder. He was still, he says, "acquiring knowledge very, very fast". Because HAI was in its infancy, in every job he filled during the first few years he had an American opposite number, sometimes with 30 years' experience of the industry. "Those counterparts could pass on not only technical advice but also management skills, and an understanding of the workings of the international market." The tuition that he received gave Mendoros a profound respect for GE, but at the same time he learned something about the limitations of giant companies.
After five years, and aged about 30, he was appointed programme manager for all foreign engine maintenance contracts. Although HAI was capable of servicing every aircraft owned by the Greek Government, it was also greedy for export business. The organisation has assembled civil aircraft parts for British Aerospace, for example. It has also won engine maintenance contracts from the NATO Central Procurement Office, from the United States Air Force in Europe and from the UK Ministry of Defence - for the GE-engined Phantom - among others. As programme manager, Mendoros was responsible for establishing contacts, negotiating requirements and ensuring that contractual obligations were met. At this stage he no longer had any Americans holding his hand. And during his four years in the job he had the satisfaction of seeing all three major contracts renewed in competitive tender.
He was now in line for promotion to some of the most senior positions in the - admittedly small - Greek aerospace industry. But it was when he was programme manager that he became aware of the market opportunity that led to his abrupt change of course. The fact was, Mendoros explains, that while the bigger defence contractors often gave their government customers excellent service, they were not at all keen on performing minor jobs, or good at responding to sudden demands. They had spent heavily on facilities and they wanted a nice, even flow of work. "The big companies had high overhead expenses. They didn't want small contracts - they were headaches."
But the gap was wider than that. Many of the aircraft in service with the world's armed forces are elderly designs, and powered by "mature" engines with maybe another five or seven years of useful life. "The big companies were not going to invest in equipment for maintaining these engines," argues Mendoros. "The defence ministries had to bend their ears to get the work done ... I was convinced that a small company with sound quality credentials and low overhead expenses, and with a team of highly skilled and capable engineers, could get a good portion of these smaller contracts."
There were several reasons why he believed that Britain was where such an enterprise should be. The country possessed a substantial defence industry - including, in Rolls-Royce, the biggest aero-engine manufacturer in Europe. As a by-product of this, UK quality standards in aero-engineering were internationally accepted. In addition, British membership of NATO and of the Commonwealth held out the possibility of access to a multiplicity of markets. Lastly, in January 1988, when Mendoros arrived in Britain - having turned down the carrot of promotion - the economy was booming. The same cannot be said today but at least the other conditions still apply.