While "Air Force One" (the President) and "Air Force Two" (the Vice President) are internationally recognized, there is no official "Air Force Three" in the United States military designation system. The call sign of any U.S. Air Force aircraft is changed to "Air Force One" the moment the President steps on board, regardless of the specific tail number. However, the term "Air Force Three" is occasionally used in popular culture or as a "joke" call sign, but it has no formal standing. In some contexts, people mistakenly apply the label to the aircraft used by the First Lady or the Secretary of State, but these flights typically use the call sign "SAM" (Special Air Mission) followed by the aircraft's tail number. There have been instances where local air traffic controllers or crews have used "Air Force Three" informally for a third aircraft in a presidential motorcade or for a backup plane, but it is not a protected title. In 2026, the primary presidential fleet consists of the two highly modified Boeing 747-200B series (VC-25A), and the new Boeing 747-8 series (VC-25B) aircraft are currently entering service, but they will still only ever be "Air Force One" when the Commander-in-Chief is present on the manifest.