Doomsday Plane
All protective measures happen for the POTUS, and Air Force One features a “doomsday plane.” Basically, it has the back of Air Force One and can stay up in the air for days, outrunning nuclear weapons. Its only job is to protect the POTUS.
Large Flying Fortress
Air Force One helps presidents go to and from various destinations, but it’s also a flying fortress that will secure and protect the POTUS and other passengers. Every window is gunfire-resistant and armored, and the craft can release flares as needed.