It’s been called “Heir rage” and “plane wars” but there appears to be little substance in claims that the Prime Minister was annoyed after Prince Charles “stole” her plane.
It is true, however, that the one RAF jet reserved for royals and senior government ministers could not be in two places at once.
So when the Prime Minister booked her trip this week to Saudi Arabia, Downing Street discovered her plane was already taken.
Prince Charles and Camilla were on it - as they jetted to Romania, Italy and Austria on their Spring tour.
I was on the plane with the Prince of Wales last week – and, having also travelled on it with the Prime Minister, I had presumed Theresa May had no plans for the plane and had allowed the royal party to use it instead.
But in the event, she did need to get somewhere – and had to pay out for a charter.
Her usual aircraft is an RAF Voyager.
It was ordered by David Cameron after he had spent many years chartering planes for official visits overseas.
We’d use planes that had just dropped off some oil executives in Angola, or a team of Texan cheerleaders.
Once, Downing Street’s female members of staff were excited to learn that George Clooney had been on the plane just a few days before.
David Cameron was always the only world leader to arrive at major summits on a plane which wasn’t “his”.
The US President, of course has Air Force One (actually he has two of them).
The President of France and leaders of Italy and Germany have them too.
And you should see the fleet of jets used by the leaders inthe Gulf states (no expense whatsoever is spared there).
It’s actually an RAF refuelling jet fitted out with somebusiness class seats in the front and middle sections – and standard airlineseats at the rear.
But there is – only one.
It appears on this occasion, Clarence House made the booking first – which meant Theresa May’s team had to go hunting for a plane to take her and her team to Saudi.
So, the key question might be: has it cost the taxpayer any more money? Well, unless you’d rather we banned all royal tours and Prime Ministerial travel – then these things are going to cost.
But as both Prince Charles’ office and Theresa May’s office say to me today, one of them would have had to charter a plane as their travel plans had collided.
The government could of course spend money fitting out more RAF jets for royal and prime ministerial use – but I rather suspect that would be a very unpopular move.