Narrative:

Pack overheat that could not be controlled. Declared emergency. Air return to [departure airport]. Overweight landing of 167;000 lbs.

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Original NASA ASRS Text

Title: B737-800 Captain experienced uncontrollable pack overheat; declared emergency and returned to departure airport.

Narrative: Pack overheat that could not be controlled. Declared emergency. Air return to [departure airport]. Overweight landing of 167;000 lbs.

Data retrieved from NASA's ASRS site as of July 2013 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.