Passengers on commercial flight stunned to find Prince William, Kate Middleton on board

Passengers traveling to Scotland were shocked to find Prince William and Kate Middleton along with family exiting from the economy FlyBe plane, which was heading from Norwich to Aberdeen.

The Duke and Duchess of Cambridge got into awaiting cars with their three children - Prince George, Princess Charlotte and Prince Louis - and their long-time nanny Maria Teresa Turrion Borrallo, reported Fox News.

The family of five were heading to Balmoral for Queen Elizabeth II's summer retreat.

The 37-year-old William was seen carrying some of his bags and sought help from his 6-year-old son George, while Charlotte happily followed them. Middleton carried Louis in her arms as she walked alongside Borrallo.

"Earlier in the flight I'd had the feeling that someone had come on the plane that I'd recognized -- but I thought it was just a footballer," a passenger told The Sun, as reported by People. "We landed, and people then saw two black Range Rovers on the tarmac."

"Suddenly, Will, Kate, and the kids all got up, and left," the passenger continued. "They weren't harassed by anyone at all as they got off the plane. They just seemed like a family traveling together, to be honest. No one saw them get on the plane either. It was amazing how they did it -- they must have slipped on quietly after people were already seated."

The family's trip comes just days after the Duke and Duchess of Sussex, Prince Harry, and Meghan Markle were slammed over their use of private jets, despite their professional commitments of fighting global climate change.

The Daily Mail previously reported as cited by People that Harry and Markle, had enjoyed four private flights in 11 days.