BeatrixFan said:
That's right. William's on his own.
The Queen can't fly with Charles and William.
Charles can't fly with Wiliam.
But everyone else can fly with everyone else.
The reason is in case there is an accident the country doesn't lose both the monarch and heir and heir's heir at the same time.
The origin of this is the accident to Prince Philip's sister in 1937 when his sister, her husband and two of their children died in a plance crash. The British government then declared that the monarch couldn't fly with the heir, once the heir is over 12.
When the Queen came to Australia in 1970 she flew up to the city near my home town but Charles couldn't come because it was only a short visit (about 4 hours) so we only had the Queen, Philip and Anne - it was a great day even if we didn't get the POW.
When Charles and Diana came here in 1983 with William he did fly on the same plane but he was under 12 at the time.
They did make an exception when the Queen Mother died and allowed William to fly back to Britain with both his father and brother. Normally William flies on his own and Harry with Charles but William and Harry could fly together and have Charles go on his own.
As the men are now older the chances of the three of them even wanting to fly to the same place is getting remoter.