Prince Charles is a vocal advocate for the lowering of aircraft emissions. He recently travelled to the University of Cambridge to discuss the cause with university scientists.

Charles's good intentions, however, were called into question by some after details of the Prince's own air travel emerged. For his journey to Cambridge, Charles took a private helicopter from Highgrove to Cambridge. The travel was for 100 miles and cost $20,000.

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Prince Charles, Prince of Wales, waves as he attends the Royal Cornwall Show on June 07, 2018.

The Royal Family defends Charles

A spokesman for the Royal Family defended the Prince amid the allegations. The statement reads: 

"The prince is not personally involved in decisions around his transportation arrangements, though he ensures all carbon emissions are offset every year. They are made based on what is possible within the constraints of time, distance, and security."

Prince Charles in 2009

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Will Charles respond to his critics?

The Prince's busy schedule accounts for his reliance on air transportation. Still, many are unhappy about the emissions and costs of Charles's flights.

It was even reported by the BBC that Prince Charles's transportation costs were over $1.7 million in the last year alone. It remains to be seen if the Prince will address the controversy himself.