Two empty jets flew some 500 miles to form part of the Duke and Duchess of Cambridge's journey to Aberdeen.

William and Kate were earlier this week praised for using an economy flight from Norwich with their two children, with many comparing it to Prince Harry and Meghan's private jet trips.

But in information obtained by The Scotsman, it is understood the empty flights made by the two 49-seat aircraft on behalf of Flybe cost around four tonnes of carbon.

According to an aviation source close to the situation, the plane which normally flies the route, Loganair, had been replaced by a Flybe-branded aircraft to 'maximise press coverage' for the company.

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Flight logs show that the plane flew 123 miles down to Norfolk - and its identification number EZE041P reportedly indicated it was empty.

Loganair's own Embraer plane then flew empty some 400 miles from Norwich to Aberdeen, to operate the next flight back to Norwich.

A spokeswoman for Flybe said the decision to change the aircraft had been Eastern's.

“We were delighted to welcome the Duke and Duchess of Cambridge and their family onboard one of our flights again, this time operated by our franchise partner, Eastern Airways," she said.

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“Please note that operational decisions generally are managed exclusively by Eastern on any route they operate under the franchise agreement, hence we are not in the position to comment.”