The carrier I used to work for had the papal contract for flights to, from, and in the USA the many years.
They were always charters. And a huge deal, where half of first class would be removed to put in a temporary bedroom. And he had quite an entourage of security, medical staff, and all the rest.
We’d supply 2 customized jets, one to use and one as spare. Each with a full crew. All of whom were volunteers and were Catholic.
It was a Big Deal.