Description

On 22 September 2008, a Boeing 757-200 being operated by American Airlines on a scheduled passenger flight from Seattle/Tacoma WA to New York JFK lost significant electrical systems functionality en route. A diversion with an emergency declared was made to Chicago O’Hare where after making a visual daylight approach, the aircraft was intentionally steered off the landing runway when the aircraft commander perceived that an overrun would occur. None of the 192 occupants were injured and there was only minor damage to the aircraft landing gear.

Investigation

An investigation was carried out by the National Transportation Safety Board (USA) (NTSB). FDR and 2 hour Cockpit Voice Recorder (CVR) data were available to the Investigation. It was established that prior to departure from Seattle-Tacoma, the flight crew had noted that the SBY AH was unpowered and after cycling the SBY Power Selector and the Battery Switch, a number of related status messages were displayed on the EICAS. Maintenance personnel attended the aircraft, cleared the messages and “told the crew they were good to go" without making any technical log entry.