Narrative:

After a normal preflight, taxi, deice, takeoff and climb, the cabin altitude alert went off shortly after climbing through 10000 ft MSL after departing cvg to the north. I leveled the airplane at 12000 ft with the altitude hold button, and put on my oxygen mask. The captain said the cabin altitude showed us unpressurized and declared an emergency with cvg departure. He then asked for and received clearance to 10000 ft. I initiated descent on autoplt. The aircraft failed to capture at 10000 ft. I noticed the altitude window showed 9000 ft. I stopped the descent at 9800 ft and asked departure if we were cleared to 10000 ft or 9000 ft. They asked what we wanted. I received clearance to 9000 ft and continued the descent. In the meantime, the captain was doing the 'loss of pressurization checklist' and talking to the flight attendants in the rear of aircraft. They reported a sound of air rushing from a rear exit door (I don't know which one) with a seal that looked abnormal. They could see daylight through it. The captain advised them to stay away from the door. I don't know all the details because I was busy flying. After a smooth landing, the handle for that door was discovered popped up. There were no door messages on the oap or anything else abnormal. Descent was made at 700-800 FPM and subsequent landing was uneventful.

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Original NASA ASRS Text

Title: MD88 CREW WAS UNABLE TO PRESSURIZE THE ACFT.

Narrative: AFTER A NORMAL PREFLT, TAXI, DEICE, TKOF AND CLB, THE CABIN ALT ALERT WENT OFF SHORTLY AFTER CLBING THROUGH 10000 FT MSL AFTER DEPARTING CVG TO THE N. I LEVELED THE AIRPLANE AT 12000 FT WITH THE ALT HOLD BUTTON, AND PUT ON MY OXYGEN MASK. THE CAPT SAID THE CABIN ALT SHOWED US UNPRESSURIZED AND DECLARED AN EMER WITH CVG DEP. HE THEN ASKED FOR AND RECEIVED CLRNC TO 10000 FT. I INITIATED DSCNT ON AUTOPLT. THE ACFT FAILED TO CAPTURE AT 10000 FT. I NOTICED THE ALT WINDOW SHOWED 9000 FT. I STOPPED THE DSCNT AT 9800 FT AND ASKED DEP IF WE WERE CLRED TO 10000 FT OR 9000 FT. THEY ASKED WHAT WE WANTED. I RECEIVED CLRNC TO 9000 FT AND CONTINUED THE DSCNT. IN THE MEANTIME, THE CAPT WAS DOING THE 'LOSS OF PRESSURIZATION CHKLIST' AND TALKING TO THE FLT ATTENDANTS IN THE REAR OF ACFT. THEY RPTED A SOUND OF AIR RUSHING FROM A REAR EXIT DOOR (I DON'T KNOW WHICH ONE) WITH A SEAL THAT LOOKED ABNORMAL. THEY COULD SEE DAYLIGHT THROUGH IT. THE CAPT ADVISED THEM TO STAY AWAY FROM THE DOOR. I DON'T KNOW ALL THE DETAILS BECAUSE I WAS BUSY FLYING. AFTER A SMOOTH LNDG, THE HANDLE FOR THAT DOOR WAS DISCOVERED POPPED UP. THERE WERE NO DOOR MESSAGES ON THE OAP OR ANYTHING ELSE ABNORMAL. DSCNT WAS MADE AT 700-800 FPM AND SUBSEQUENT LNDG WAS UNEVENTFUL.

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.