Narrative:

Takeoff and climb out appeared normal through 10000 ft when we received a 'cabin altitude' caution message. I selected for the autoplt to level out instead of continuing the climb to 15000 ft as assigned. The aircraft was climbing quickly and leveled at 11400 ft. We were in the process of notifying ATC and running our QRH procedures when a cabin altitude warning appeared on the EICAS. We did the emergency memory item checklist and began our descent to 10000 ft. We notified ATC and continued down to 5000 ft, which was below the cloud layer which was from 7000-9000 ft and put us in good VFR conditions. ATC also gave us direct routing to cvg. We accomplished all required and company recommended procedures and had a normal landing in cvg. At the gate, the ground crew came up to the cockpit to notify us of the cargo door situation. The captain and I looked at it while waiting for maintenance personnel to arrive. The cargo door was closed and latched, but out of position in the upper l-hand corner. It appeared to be out of position in its track a small amount which had created our pressurization problem.

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Original NASA ASRS Text

Title: A CL65 FLT CREW HAS TO DIVERT FOR A PRESSURIZATION PROB CAUSED BY A CARGO DOOR NOT BEING ON ITS TRACKS.

Narrative: TKOF AND CLBOUT APPEARED NORMAL THROUGH 10000 FT WHEN WE RECEIVED A 'CABIN ALT' CAUTION MESSAGE. I SELECTED FOR THE AUTOPLT TO LEVEL OUT INSTEAD OF CONTINUING THE CLB TO 15000 FT AS ASSIGNED. THE ACFT WAS CLBING QUICKLY AND LEVELED AT 11400 FT. WE WERE IN THE PROCESS OF NOTIFYING ATC AND RUNNING OUR QRH PROCS WHEN A CABIN ALT WARNING APPEARED ON THE EICAS. WE DID THE EMER MEMORY ITEM CHKLIST AND BEGAN OUR DSCNT TO 10000 FT. WE NOTIFIED ATC AND CONTINUED DOWN TO 5000 FT, WHICH WAS BELOW THE CLOUD LAYER WHICH WAS FROM 7000-9000 FT AND PUT US IN GOOD VFR CONDITIONS. ATC ALSO GAVE US DIRECT ROUTING TO CVG. WE ACCOMPLISHED ALL REQUIRED AND COMPANY RECOMMENDED PROCS AND HAD A NORMAL LNDG IN CVG. AT THE GATE, THE GND CREW CAME UP TO THE COCKPIT TO NOTIFY US OF THE CARGO DOOR SIT. THE CAPT AND I LOOKED AT IT WHILE WAITING FOR MAINT PERSONNEL TO ARRIVE. THE CARGO DOOR WAS CLOSED AND LATCHED, BUT OUT OF POS IN THE UPPER L-HAND CORNER. IT APPEARED TO BE OUT OF POS IN ITS TRACK A SMALL AMOUNT WHICH HAD CREATED OUR PRESSURIZATION PROB.

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.