But that didn’t stop the couple once travelling to the most dangerous airport in the world.
Paro Airport in Bhutan is tucked among the steep mountains of the Himalayas and is surrounded by sharp peaks of up to 18,000ft tall.
Only 10 pilots in the world are qualified to land at the airport in a difficult manoeuvre that involves turning sharp left to avoid the mountain and land in the valley.
Kate and William visited the remote destination on their royal tour to the region in 2016.
The royal couple were invited into the cockpit of a charter plane carrying them from Assam in India to Paro.
William admitted after the journey that he was “terrified” of the landing.
The Prince spoke to helicopter pilot Nic Suddards, 56, from Yorkshire who moved to Bhutan in December to fly their national helicopter making emergency rescues and transporting diplomats.
Nic said afterwards: “[William] said it (being in the cockpit) was terrifying.
“There is a house on the approach which is known as Mr Smith’s house and you miss it by metres.
“The pilot was showing him Mr Smith’s house and he said, ‘Don’t look at that, concentrate on the runway!’”
The airport is 1.5 miles above sea level with a runway of just 6,500 feet. This makes it one of the few runways in the world which is shorter than its elevation above sea level.
Strong winds can result in serious turbulence for planes coming into land.
They also have to weave through houses dotted across the mountainside.
Flights are only permitted during hours of daylight and the pilot is required to make his judgements by eye rather than relying on aircraft instruments.
Bhutan’s national carrier, Druk Air, and Bhutan Airlines both provide international flights into the airport.
According to the Bhutan Travel Bureau, “each flight is mesmerising and offers an exciting descent into the kingdom.”
Prince William – a helicopter pilot – missed the chance to fly out of the airport in a helicopter during his stay, Nic revealed.
He said William was “devastated,” to not fly. “He said he would have loved to have flown it,” Nic added.
On another royal tour, Kate, the Duchess of Cambridge, had a rather embarrassing public incident.