The most recognizable call sign of this type is Air Force One, used when any Air Force aircraft is transporting the U.S. President. Similarly, when the President is flown in a U.S. Marine Corps helicopter, the call sign is Marine One. When then-president George W. Bush, a former Air National Guard fighter pilot, was flown to the aircraft carrier USS Abraham Lincoln in a Navy S-3B Viking, it was the first use of the "Navy One" call sign.