Passengers 35 Fatalities 39 Date 9 July 1964 Injuries (nonfatal) 0 Survivor 0 | Crew 4 Missing 0 Number of deaths 39 Operator United Airlines Passenger count 35 | |
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Summary Loss of control after in-flight fire Similar United Airlines Flight 615, United Airlines Flight 859, United Airlines Flight 297, United Airlines Flight 610, United Airlines Flight 2860 | ||
United airlines flight 823 memorial
United Airlines Flight 823 was a scheduled flight from Philadelphia International Airport, Pennsylvania to Huntsville International Airport, Alabama with 39 on board. On 9 July 1964 at approximately 18:15 EST, the aircraft, a Vickers Viscount 745D, registration N7405, crashed 2.25 mi (3.62 km) northeast of Parrottsville, Tennessee after experiencing an uncontrollable fire on board, killing all 39. The fire of unknown origin occurred in the passenger cabin. One passenger abandoned the aircraft through the No.4 escape window prior to impact but did not survive the free-fall. "The Board is unable to identify the source of fuel, the ignition point of the fire, or the cause of the final manoeuvre." The Probable Cause finding was "The Board determines that the probable cause of this accident was an uncontrollable in-flight fire, of undetermined origin, in the fuselage, which resulted in a loss of control of the aircraft."
The accident triggered an investigation of the Lockheed L-109C Flight Data Recorder which resulted in modifications of that device and revision of the standards for all recorders. Also addressed were potential problems with the Pyrene Duo Head Model DCD-10 for the underfloor baggage and heater compartments. There was an Airworthiness Directive issued. Revisions were made to the Pilot's Manual, Viscount Maintenance and Instruction, and Accessories Manuals.
United used the Flight 823 designation on its Washington-Dulles to Mexico City, Mexico route.