On this day, December 26, 1973, Richard Nixon flew from IAD to LAX on United Flight 55.

[Dennis Donovan]

1. The obvious question is why he wasn't he flying on AF1?

Well...

https://en.wikipedia.org/wiki/Executive_One

Executive One is the call sign designated for any United States civil aircraft when the president of the United States is on board. Typically, the president flies in military aircraft that are under the command of the Presidential Airlift Group, which include Air Force One, Marine One, Army One, Navy One and Coast Guard One.

On December 26, 1973, President Richard Nixon became the only sitting president to travel on a regularly scheduled commercial airline flight when he flew on United Airlines flight 55 from Washington Dulles International Airport to Los Angeles International Airport, "to set an example for the rest of the nation during the current energy crisis" and to "demonstrate his confidence in the airlines". Nixon, first lady Pat, daughter Tricia, and 22 staffers, security, and pool purchased 13 first-class tickets at $217.64, and 12 coach tickets at $167.64 aboard the DC-10 on what is traditionally not a very busy flight, and, with an eye to security, quietly boarded the plane without fanfare to maintain secrecy prior to departure. A Nixon aide carried a suitcase-sized secure communication device on board the plane, so that the President could remain in contact with Washington in the event of an emergency.

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