Narrative:

During climb out from 18000 ft to 19000 ft, received a 'cabin altitude' caution message. After this occurred, we requested an immediate descent. ATC assigned 11000 ft and later requested lower to 10000 ft. We complied with reports to ATC through 17500 ft and was assigned an off course heading of 270 degrees from approximately 360 degrees north. Within seconds of beginning descent, we received a 'cabin altitude' warning message with a 'cabin pressure' aural message. The captain and I executed memory items and appropriate (QRH) procedures. After stabilizing at 10000 ft and completing all checklist items, we used this time to talk to the flight attendant. She notified us that all passenger were fine and never noted anything unusual. She also stated that she was fine and noticed nothing unusual as well. Since no structural damage was suspected, we opted not to declare an emergency. We were approximately 20 mins south of cvg. We opted to continue to cvg. Since all passenger reported no problems, we opted not to deploy masks (manually) so as not to frighten the passenger. The masks would have automatic-deployed if the cabin altitude exceeded 14000 ft. We never exceeded 12000 ft cabin altitude, even at our highest altitude of 18000 ft MSL. Level now at 10000 ft, we attempted to reset our right pack (acm) which had fallen off-line. Our left pack (acm) was deferred at the time per maintenance control. The right pack would not reset. Maintenance was notified en route. The passenger were spoken to twice about our situation. We landed with no further occurrence.

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Original NASA ASRS Text

Title: LOSS OF CABIN PRESSURE WHEN THE REMAINING PACK FAILS ON A CL65 60 NM S OF DEST ARPT OF CVG.

Narrative: DURING CLBOUT FROM 18000 FT TO 19000 FT, RECEIVED A 'CABIN ALT' CAUTION MESSAGE. AFTER THIS OCCURRED, WE REQUESTED AN IMMEDIATE DSCNT. ATC ASSIGNED 11000 FT AND LATER REQUESTED LOWER TO 10000 FT. WE COMPLIED WITH RPTS TO ATC THROUGH 17500 FT AND WAS ASSIGNED AN OFF COURSE HDG OF 270 DEGS FROM APPROX 360 DEGS N. WITHIN SECONDS OF BEGINNING DSCNT, WE RECEIVED A 'CABIN ALT' WARNING MESSAGE WITH A 'CABIN PRESSURE' AURAL MESSAGE. THE CAPT AND I EXECUTED MEMORY ITEMS AND APPROPRIATE (QRH) PROCS. AFTER STABILIZING AT 10000 FT AND COMPLETING ALL CHKLIST ITEMS, WE USED THIS TIME TO TALK TO THE FLT ATTENDANT. SHE NOTIFIED US THAT ALL PAX WERE FINE AND NEVER NOTED ANYTHING UNUSUAL. SHE ALSO STATED THAT SHE WAS FINE AND NOTICED NOTHING UNUSUAL AS WELL. SINCE NO STRUCTURAL DAMAGE WAS SUSPECTED, WE OPTED NOT TO DECLARE AN EMER. WE WERE APPROX 20 MINS S OF CVG. WE OPTED TO CONTINUE TO CVG. SINCE ALL PAX RPTED NO PROBS, WE OPTED NOT TO DEPLOY MASKS (MANUALLY) SO AS NOT TO FRIGHTEN THE PAX. THE MASKS WOULD HAVE AUTO-DEPLOYED IF THE CABIN ALT EXCEEDED 14000 FT. WE NEVER EXCEEDED 12000 FT CABIN ALT, EVEN AT OUR HIGHEST ALT OF 18000 FT MSL. LEVEL NOW AT 10000 FT, WE ATTEMPTED TO RESET OUR R PACK (ACM) WHICH HAD FALLEN OFF-LINE. OUR L PACK (ACM) WAS DEFERRED AT THE TIME PER MAINT CTL. THE R PACK WOULD NOT RESET. MAINT WAS NOTIFIED ENRTE. THE PAX WERE SPOKEN TO TWICE ABOUT OUR SIT. WE LANDED WITH NO FURTHER OCCURRENCE.

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.