There's one rule that the Queen must follow when she steps off a plane

There are a number of rules that royals have to follow, from the special royal wave to dinner table etiquette to the titles they receive from the Queen, and royal protocol must be adhered to when they travel, too - although Prince William breaks the rules by travelling with his family.

However, when it comes to royal etiquette there's one thing that the Queen must do when she leaves an aircraft.

According to protocol, she must descend stairs elegantly and gracefully - whether she is stepping off of a plane or leaving a venue following a royal engagement.

The family, in particular the female royals, must not bow their heads and should keep their chins parallel to the ground. They are permitted to rest their hand on a rail if they should need to, and males who are escorting them can offer their arm, but otherwise they must keep their hands at their sides.

The need for their descent to be graceful can be tricky, especially when exiting a plane as it is often very windy. But to ensure that her skirt doesn't raise during a gust, the monarch uses a very simple and clever trick.

Author Robert Hardman says: 'She buys small lead weights from the curtain department at Peter Jones and sews them into the royal hemlines, not only to maintain the shape of the Queen’s clothes but to prevent what would now be called a "wardrobe malfunction".'

It appears that younger royals also use this as a way to keep their skirts and dresses from moving, as well as wearing bodysuits underneath.

Myka, founder of Beaumont Etiquette, told Marie Claire US that Kate Middleton and Meghan Markle wear 'bodysuits and clothes that actually increase static so it’s much hard for something to fly up.'

She said: 'I know when I went to finishing school we were taught that when you are on the tarmac, if you do not use weights or heavy weighted material, you make sure it will not fly up by wearing under garments that keep the fabrics connect to your body.'

Very clever!