Narrative:

After leveloff at FL350 the altitude warning horn sounded, indicating the cabin altitude reached 10000 ft. We donned oxygen masks and ran the appropriate checklists as we stared descent to 10000 ft. Cabin altitude should have stopped at 5200 ft. The passenger oxygen masks deployed at 13000 ft cabin altitude. They should have deployed at 14000 ft. We leveled at 10000 ft without incident. When the altitude horn sounded at 10000 ft cabin altitude, the cabin VV1 (vertical speed) showed 1200 FPM climb. The pressure controller was changed and the next leg was flown without incident.

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Original NASA ASRS Text

Title: CABIN PRESSURIZATION LOSS AT 35000 FT.

Narrative: AFTER LEVELOFF AT FL350 THE ALT WARNING HORN SOUNDED, INDICATING THE CABIN ALT REACHED 10000 FT. WE DONNED OXYGEN MASKS AND RAN THE APPROPRIATE CHKLISTS AS WE STARED DSCNT TO 10000 FT. CABIN ALT SHOULD HAVE STOPPED AT 5200 FT. THE PAX OXYGEN MASKS DEPLOYED AT 13000 FT CABIN ALT. THEY SHOULD HAVE DEPLOYED AT 14000 FT. WE LEVELED AT 10000 FT WITHOUT INCIDENT. WHEN THE ALT HORN SOUNDED AT 10000 FT CABIN ALT, THE CABIN VV1 (VERT SPD) SHOWED 1200 FPM CLB. THE PRESSURE CTLR WAS CHANGED AND THE NEXT LEG WAS FLOWN WITHOUT INCIDENT.

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.