Air Force One
Air Force One is the term used to identify any aeroplane on which the President of the United States is flying. It is an official call sign used by air traffic control.
Franklin Roosevelt was the first president to fly Air Force One (designated VC-54A) when he flew to the Yalta Conference aboard a Douglas C-54 Skymaster which was built for presidential use. The Skymaster had a conference room, state room and bathroom and featured a bullet-proof picture window. To accommodate Roosevelt, who used a wheel chair, there was an elevator added to help him enter and exit the plane. Affectionately known as "the Sacred Cow" by journalists the Skymaster was used once by Roosevelt who died in 1945. In 1947, the Spymaster was moved to other flying duties and was retired from service in 1961. The Skymaster was a propeller driven airplane.
During the President Harry Truman's administration a modified Douglas C-118 Liftmaster was selected as Air Force One. The Liftmaster was a military version of the civilian DC-6 airplane and was named Independence to honor Truman's hometown of Independence, Missouri. The Independence featured a pressurized cabin, 24 passenger seats, and the president's quarters had a reclining swivel chair with a full-sized sofa bed. The C-118 Liftmaster, another propeller driven airplane, remained in service until 1953.
In 1962, the Air Force One entered the jet age when a Boeing 707 was used to fly President John Kennedy on his presidential trips. It was at this time Air Force One was painted its familiar blue-and-white design created by Raymond Loewy. This same Boeing 707 was the location where Vice President Lyndon B. Johnson was sworn in as president of the United States after President John Kennedy was assassinated.
In 1972, a replica 707 with the tail number 27000 was added to the Air Force One fleet. The 27000 was used as a back-up craft and was the one used to fly President Richard Nixon after he resigned from office in 1974. Since 1972 two Air Force One jets have been used to fly the president or vice president. The call sign used when the president is on board is Air Force One.
The current two Air Force One jets, both of which are Boeing 747-200B series jets, carry the tail codes 20000 and 29000 respectively. The Air Force designation for the aircraft is VC-25A. Aboard Air Force One the president has access to an on board medical suite and a doctor available, if needed. Air Force One has two galleys that can feed up to 100 people, and 4,000 feet of space on the jet. Quarters are available for traveling guests, Secret Service and the press.
You can visit the Reagan Library located in where you can see what Air Force One the jet President Reagan used during his presidency.
Air Force One jets are maintained and operated by the Presidential Airlift Group, part of the White House Military Office. The Airlift Group was founded in 1944 as the Presidential Pilot Office at the direction of President Franklin D. Roosevelt.
References
Brittanica https://www.britannica.com/topic/Air-Force-One
The Grounds Air Force One: The President's Office In the Sky: https://web.archive.org/web/20220706062848/https://www.whitehouse.gov/about-the-white-house/the-grounds/air-force-one/
How Air Force One Works: https://people.howstuffworks.com/air-force-one6.htm
Ronald Reagan Presidential Library and Museum Air Force One Pavilion: https://www.reaganlibrary.gov/permanent-exhibits/air-force-one-pavilion