[1]: 7  The Boeing 727 was delivered to American Airlines on June 29, 1965, and had operated a total of 938 hours at the time of the accident.

[1]: 2  The aircraft approached the airport from the southeast and turned to a northerly heading to cross the Ohio River.

[1]: 1  CAB investigators concluded that the aircraft was working normally and fully under the control of the pilots at the time of the crash.

[2] The flight data recorder showed the aircraft descended through 500 feet (150 m) in the last 42 seconds before impact, a normal rate of descent for the landing phase of operation.

The CAB determined that the probable cause of the accident was the pilots' failure to properly monitor their altitude during a visual approach into deteriorating weather conditions.

[1]: 26 It was later believed that the following factors might have contributed to the crash:[3] The estate of Samuel Creasy, one of the passengers who died aboard Flight 383, sued American Airlines for wrongful death.

American Airlines responded by filing a third-party complaint against the Federal Aviation Administration and the Weather Bureau, in an attempt to shift liability for the crash to meteorologists and air traffic controllers for failure to warn the pilots of inclement weather or revoke the visual approach clearance.