A man who flew over a Canadian city while held aloft by more than 100 helium balloons attached to a chair has been fined almost $20,000 (£16,000, €18,500) for his effort.

At a court in Alberta, Judge Bruce Fraser heard Daniel Boria, 27, who pleaded guilty in December to dangerous operation of an aircraft, strapped the balloons to a lawn chair in July 2015 and drifted more than two miles over Calgary.

Prosecutors said Boria's flight interfered with the flights of commercial aircraft and put hundreds of people in danger.

Fraser said in Friday's sentencing that Boria's flight was "dumb and dangerous" as well as "unconscionably stupid".

"There was nothing fantastic, fun or exhilarating about it," Fraser said. "There is no precedent for so foolish an escapade."

Fraser approved a plea agreement to have Boria pay a $3,750 fine and make a $15,000 donation to charity.

Boria, whose stunt was meant to promote his cleaning company, was unrepentant outside of court. "Why climb the highest mountain?" he told CBC News. "Why 85 years ago fly the Atlantic? Why do the Oilers play the Flames? I chose to fly a chair; not because it is easy but because it is hard. Because that goal served to organise and measure the best of our energies and skills."

"[They] didn't charge the Wright brothers," Boria said. "It's pretty hard to take it seriously when you guys are asking me these questions based on me flying a lawn chair."