Martin Bromage was attempting the 18,000km voyage to raise £150,000 for charity Help for Heroes.
In an interview with the Sun newspaper before he set off, Bromage revealed how he had sold his personal possessions, including gardening equipment and his car, to pay for the trip.
Arboricultural Association director Nick Eden, who had worked closely with the Cheltenham-based businessman in the past, paid tribute to Martin Bromage.
"It is tragic and our thoughts go out to all of Martin's family and work colleagues, and people in the arboriculture industry who knew and worked with him over the years," he said.
"He developed a web business he ran alongside his tree firm and for a while the Arboricultural Association engaged Martin to run the website.
"Martin also managed to secure our website address www.trees.org.uk. It is a lasting memory for the Arboricultural Association."
The 49-year-old set off from Gloucestershire Airport for the first leg of the journey — to Le Touquet, in northern France on Monday morning (18 January) but ran into bad weather.
He was aiming to be only the second person in history to complete the journey in a "flex wing" microlight.
Dover Coastguard confirmed that his body had been found by a French patrol boat at 10pm on 18 January, two miles from Boulogne.
Eden added: "He was courageous, adventurous and very generous."
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