Was Replaced One Time
It is the responsibility of any sitting POTUS to use Air Force One as it is intended—as the only transportation for the president. However, during the Nixon administration, that basic rule was broken. In an effort, by Nixon, to demonstrate and send a political-economic message to the people, the POTUS do the unthinkable and traveled via United Airlines. Even though he was trying to prove and illustrate a point, his fellow representatives in the administration did not see this as a prudent move. Since he was not traveling in Air Force One, the United Airlines aircraft was given the designation of Executive One. This was and continues to be the callsign when the sitting POTUS chooses to board a civilian aircraft.
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