The Voyager, a British Royal Air Force jet transporting the couple during their five-day tour of Pakistan, was caught in one of the thunderous storms that periodically rock the capital in October.
“The pilot circled for an hour but the lightening – and turbulence – was so bad we had to fly back,” tweeted the Daily Mail’s royal correspondent Rebecca English, who was on board the plane.
“Few of us have experienced turbulence as bad as that,” she added.
“If I’m honest … that was the most nervous I’ve ever felt in a plane,” added ITV royal correspondent Chris Ship.
Daily Telegraph correspondent Ben Farmer said the pilot had tried to land twice, once at a military base in the garrison city of Rawalpindi adjacent to Islamabad, and once at Islamabad International before abandoning the attempt and returning to Lahore, some 270 kilometres (170 miles) flying distance away.
However all on board appeared to be safe, with English tweeting that Prince William — himself a pilot — had joked with the press pack that he had been flying.
English said it was unclear when they would be able to take off again. There was no immediate statement from Kensington Palace.