Narrative:

Shortly after takeoff in climb out we experienced a pack 2 valve close that could not be reset. Determined max alt of 25;000. We leveled at 24;000 and worked fuel numbers for the remainder of the flight. Shortly after; a pack 1 overload message appeared and both packs shut down. We [notified ATC] and began a descent to 10;000 ft requesting vectors to return to [departure airport]. Determined that we were roughly 2500 lbs overweight and began burning fuel for a normal landing. Once landing weight was achieved a normal ILS approach then accomplished with no further incident.cabin pressurization system failed.

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Original NASA ASRS Text

Title: EMB-140 flight crew reported returning to departure airport after first losing one pack and then the other.

Narrative: Shortly after takeoff in climb out we experienced a pack 2 valve close that could not be reset. Determined max alt of 25;000. We leveled at 24;000 and worked fuel numbers for the remainder of the flight. Shortly after; a pack 1 overload message appeared and both packs shut down. We [notified ATC] and began a descent to 10;000 ft requesting vectors to return to [departure airport]. Determined that we were roughly 2500 lbs overweight and began burning fuel for a normal landing. Once landing weight was achieved a normal ILS approach then accomplished with no further incident.Cabin pressurization system failed.

Data retrieved from NASA's ASRS site 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.