A United Airlines Boeing 247 is destroyed by sabotage, the first such proven case in the history of commercial aviation.

United Air Lines Flight 23

1933 aircraft bombing in Indiana, United States

United Air Lines Flight 23 was a regularly-scheduled flight operated by United Air Lines between Newark, New Jersey, and Oakland, California, with intermediate stops. On October 10, 1933, the Boeing 247 airliner serving the flight—registered as NC13304—exploded and crashed near…