Narrative:

A problem occurred with pressurization that we were unable to correct. At approximately FL190 we got a cabin altitude warning and performed the red box immediate action items. We declared an emergency and returned to our departure airport for a normal smooth not overweight landing.

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Original NASA ASRS Text

Title: An air carrier flight crew of an unidentified aircraft type declared an emergency and returned to their foreign departure airport when the aircraft failed to pressurize.

Narrative: A problem occurred with pressurization that we were unable to correct. At approximately FL190 we got a cabin altitude warning and performed the red box immediate action items. We declared an emergency and returned to our departure airport for a normal smooth not overweight landing.

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.