Prince George's strict travel ban that will be put in place after his 12th birthday

When it comes to the globetrotting habits of the Royal Family, there's a treasure trove of strict and intriguing protocols in place to ensure their safety while abroad.

These range from bringing their own alcohol to sidestep any potential poisoning attempts, to always packing an outfit suitable for mourning in case of unexpected deaths, with each rule deeply rooted in royal tradition.

One particularly interesting regulation exists to protect the line of succession by controlling which royals can fly together. At present, Prince William is allowed to travel with his young children, but as they grow older, this will have to change, OK! reports.

On HELLO Magazine's 'A Right Royal Podcast', former pilot to King Charles, Graham Laurie, divulged how this policy affected Prince William starting when he turned 12 in 1994.

He told listeners: "Interestingly, we flew all four: the Prince, the Princess, Prince William and Prince Harry, up until Prince William was 12 years old.

"After that, he had to have a separate aircraft and we could only fly all four together when they were young with the written permission of Her Majesty. When William became 12, he would fly normally in a 125 from Northolt and we would fly the 146 out with the other three on."

In the next couple of years, Prince George, who is currently 10, will also have to follow this rule and it's anticipated that he'll start travelling separately from his father, Prince William.

It remains to be seen whether George will continue to travel with his mother Kate and his siblings, or if William will be the one taking solo flights.

This unique rule exists to protect the line of succession. While the monarch can grant permission to break this rule, it's generally discouraged for two direct heirs to travel on the same flight.

This is due to the potential risk of immediate instability in the monarchy in the unfortunate event of a crash. Although plane crashes are rare these days, three members of the Royal family have tragically lost their lives in air accidents in the past.

Prince Philip's sister, Princess Cecile, died in a crash in 1937. The late Queen's uncle, Prince George, Duke of Kent, died in 1942. And her cousin, Prince William of Gloucester, died while participating in an air show in 1972.

This isn't the only significant travel rule that the royals must adhere to. Just like his mother before him, the King always travels with a supply of blood and a doctor on hand at all times.

Another essential item that every Royal woman carries with them is a black dress. When her father, King George VI, passed away in 1952, the Queen was on a Royal tour in Kenya and didn't have a black dress packed for her unexpected return to the UK.

Upon landing at London Airport, a suitable dress was brought on board for her to change into before she disembarked from the plane.

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