Narrative:

Cruising at 31000 ft, left pack tripped, cabin started to climb. Made immediate descent to FL240. Cabin was still climbing, so continued descent to FL190 and requested from ZMA clearance direct to mia. Leveled at FL190. Cabin hit 10000 ft and warning horn sounded, descended to 14000 ft still hoping to control cabin, but just before reaching 14000 ft, cabin climbed rapidly and masks deployed. Declared emergency and made descent to 10000 ft. At 10000 ft, cabin was indicating about 9000 ft. After a few mins at 10000 ft, made PA then descended to 8000 ft and maintained 8000 ft until reaching mia. Several passenger were extremely anxious and did not feel well. On arrival at mia, paramedics met aircraft and ended up taking 3 to hospital, one of whom had previously had 2 heart attacks. In retrospect, if we had made immediate descent to 10000 ft, we would have possibly avoided passenger anxiety with the masks dropping. Complicating factors were that many passenger spoke no english and, even though 3 flight attendants were spanish speakers, were not sufficiently reassured there was no real problem. Lack of immediate descent to 10000 ft was also affected by confidence that 1 pack should be able to hold pressure adequately, and knowledge that immediate descent to below 10000 ft would result in loss of radar and VHF radio contact with center. (Radio contact was maintained by aircraft relays.) in the future, I will be more oriented toward how the passenger will react to abnormal sits. We were not affected by the higher than normal cabin altitude and failed to appreciate the condition of passenger who were in poor health to begin with, and what their capacities were.

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Original NASA ASRS Text

Title: ACR HAS PRESSURE PACK FAILURE. STEP DOWN DSCNT CAUSES OXYGEN MASKS TO DROP.

Narrative: CRUISING AT 31000 FT, L PACK TRIPPED, CABIN STARTED TO CLB. MADE IMMEDIATE DSCNT TO FL240. CABIN WAS STILL CLBING, SO CONTINUED DSCNT TO FL190 AND REQUESTED FROM ZMA CLRNC DIRECT TO MIA. LEVELED AT FL190. CABIN HIT 10000 FT AND WARNING HORN SOUNDED, DSNDED TO 14000 FT STILL HOPING TO CTL CABIN, BUT JUST BEFORE REACHING 14000 FT, CABIN CLBED RAPIDLY AND MASKS DEPLOYED. DECLARED EMER AND MADE DSCNT TO 10000 FT. AT 10000 FT, CABIN WAS INDICATING ABOUT 9000 FT. AFTER A FEW MINS AT 10000 FT, MADE PA THEN DSNDED TO 8000 FT AND MAINTAINED 8000 FT UNTIL REACHING MIA. SEVERAL PAX WERE EXTREMELY ANXIOUS AND DID NOT FEEL WELL. ON ARR AT MIA, PARAMEDICS MET ACFT AND ENDED UP TAKING 3 TO HOSPITAL, ONE OF WHOM HAD PREVIOUSLY HAD 2 HEART ATTACKS. IN RETROSPECT, IF WE HAD MADE IMMEDIATE DSCNT TO 10000 FT, WE WOULD HAVE POSSIBLY AVOIDED PAX ANXIETY WITH THE MASKS DROPPING. COMPLICATING FACTORS WERE THAT MANY PAX SPOKE NO ENGLISH AND, EVEN THOUGH 3 FLT ATTENDANTS WERE SPANISH SPEAKERS, WERE NOT SUFFICIENTLY REASSURED THERE WAS NO REAL PROB. LACK OF IMMEDIATE DSCNT TO 10000 FT WAS ALSO AFFECTED BY CONFIDENCE THAT 1 PACK SHOULD BE ABLE TO HOLD PRESSURE ADEQUATELY, AND KNOWLEDGE THAT IMMEDIATE DSCNT TO BELOW 10000 FT WOULD RESULT IN LOSS OF RADAR AND VHF RADIO CONTACT WITH CTR. (RADIO CONTACT WAS MAINTAINED BY ACFT RELAYS.) IN THE FUTURE, I WILL BE MORE ORIENTED TOWARD HOW THE PAX WILL REACT TO ABNORMAL SITS. WE WERE NOT AFFECTED BY THE HIGHER THAN NORMAL CABIN ALT AND FAILED TO APPRECIATE THE CONDITION OF PAX WHO WERE IN POOR HEALTH TO BEGIN WITH, AND WHAT THEIR CAPACITIES WERE.

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.