By now you might have heard that the plane carrying Pope Francis is referred to as 'Shepherd One', just like Air Force One when Obama is on board and Harambee One when carrying the Kenyan President. Well, here are five things you need to know about the plane carrying the Pontiff. 

1. The plane isn’t really called “Shepherd One.” People in the United States call it that, but the phrase is a media conceit rather than an actual call sign.

The papal plane doesn’t have a name. Its designation is usually just Alitalia flight AZ 4000 on the outbound leg, and beyond that Italians simply call it the volo papale, or “papal flight.”

2. The pope doesn’t own the plane. The term “Shepherd One” suggests that the pope actually owns a plane, which he doesn’t. Even the term “papal plane” is something of a myth, since the pontiff does not have his own personal aircraft.

The Vatican always charters a plane for the three or four foreign trips a pope usually makes every year, often using a different aircraft for each leg of the journey.

3. The plane is nothing like Air Force One. Calling the plane “Shepherd One” suggests an analogy with Air Force One, summoning images to mind for Americans of conference rooms with large round tables, a presidential suite, red hotline phones, communications rooms with technicians tracking satellite telemetry, and so on.

Nothing could be further from the truth. In reality, the papal plane is a normal commercial jet, and usually the only real perk enjoyed by the pontiff is that he gets to sit in the first row of business class by himself.

Read more fun facts about 'Shepherd One' .