Narrative:

Approximately one hour after takeoff I was contacted by ACARS and informed that the flight was to return to the departure airport. I contacted dispatch (who conferred with the dispatch supervisor and the 767 mechanic in maintenance control) and was told I had a problem with the APU battery and should declare an emergency and land overweight. After dumping all fuel from center tank and declaring an emergency an overweight landing was performed without incident.

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Original NASA ASRS Text

Title: B767 Captain is informed airborne that the wrong APU battery had been installed in his aircraft and they should dump fuel and return immediately.

Narrative: Approximately one hour after takeoff I was contacted by ACARS and informed that the flight was to return to the departure airport. I contacted Dispatch (who conferred with the Dispatch Supervisor and the 767 Mechanic in Maintenance Control) and was told I had a problem with the APU battery and should declare an emergency and land overweight. After dumping all fuel from center tank and declaring an emergency an overweight landing was performed without incident.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.