Narrative:

Cruising at FL310 a rapid loss of cabin pressure was felt and observed on cabin pressure instrument along with a red cabin warning light and horn. A 7700 rapid descent was initiated to 10000. Flight proceeded normally from that point to destination. After parking a tear was found in cabin door seal. Believe this was the cause of pressurization problem.

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Original NASA ASRS Text

Title: LOSS OF PRESSURIZATION AT 31000 FT. EMER DSCNT.

Narrative: CRUISING AT FL310 A RAPID LOSS OF CABIN PRESSURE WAS FELT AND OBSERVED ON CABIN PRESSURE INST ALONG WITH A RED CABIN WARNING LIGHT AND HORN. A 7700 RAPID DSCNT WAS INITIATED TO 10000. FLT PROCEEDED NORMALLY FROM THAT POINT TO DEST. AFTER PARKING A TEAR WAS FOUND IN CABIN DOOR SEAL. BELIEVE THIS WAS THE CAUSE OF PRESSURIZATION PROBLEM.

Data retrieved from NASA's ASRS site as of July 2007 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.