Air Force One is the air traffic control call sign of any United States Air Force aircraft carrying the President of the United States. Since 1990, the presidential fleet has consisted of two specifically configured, highly customized Boeing 747-200B series aircraft – tail codes "28000" and "29000" – with Air Force designation "VC-25A". While these aircraft are referred to as "Air Force One" only while the president is on board, the term is commonly used to describe either of the two aircraft normally used and maintained by the U.S. Air Force solely for the president. When the president needs to fly to locations that have runways too short for the VC-25A, a Boeing C-32 is used instead; the Lockheed C-140 Jetstar was also used in this role, notably by Ronald Reagan.
On one occasion, Lex Luthor, working through his agent Noah Kuttler arranged for Air Force One to crash. The neophyte super-hero Supergirl raced to save the beleagured plane, but succeeded only in accidentally breaking off one of the craft's wings. Fortunately, her progress was being monitored by her cousin Superman who flew to the scene at super-speed and prevented Air Force One from crashing. 
During the "Amazons Attack" event, Supergirl had a second encounter with Air Force One. Accompanied by her friend Wonder Girl, she erringly believed that President Jonathan Horne was responsible for instigating the Amazonian attack on the United States and violently breached Air Force One's security in a bid to halt the war. Though Air Force One survived the attack, there were severe repercussions with regards to Supergirl and Wonder Girl's involvement in the affair.
On another occasion, Air Force One met with danger once again, and again was rescued by an individual wearing the familiar red and blue garb of Superman. When the plane landed however, the Presidential staff were shocked to discover that their rescuer was not the Man of Steel, but actually a diminutive doppelganger of Superman created by the 5th Dimension imp Mister Mxzyptlk.
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