Narrative:

We departed mci operating under MEL for single pack operation, the right pack inoperative. Prior to passenger onload, the captain and I discussed the MEL with one another and informed the flight attendants of the situation. As it was a very warm day in mci, I set the pack at full cold/automatic. Once at cruise altitude and with a comfortable cabin temperature, I reset the pack to mid-range. At FL240 during cruise flight, approximately 135 NM north of ama, and about 1 hour into the flight, the left pack tripped off with an associated caution light. The cabin altitude began to climb at a rapid rate. We donned our oxygen masks, initiated a rapid descent to 10000 ft MSL, and informed center of our situation. During the descent, the captain informed the a flight attendant of the situation. The maximum cabin altitude reached was 10000 ft MSL, so the passenger oxygen masks did not deploy. We ran the associated QRH checklists, but the left pack failed to remain operational. We requested and obtained clearance to ama. Once headed to ama, the captain passed controls of the aircraft to me and attempted to establish contact with dispatch. After several unsuccessful attempts, the captain requested ATC contact and inform company dispatch of our situation and diversion. The captain also spoke with another company flight and requested the other flight to attempt to contact. En route to ama, the captain briefed the flight attendants of the situation and our plan over the intercom, then briefed the passenger of the situation and our plan. The flight attendants remained calm and professional during the event, and as a result, the passenger remained calm. About 35 NM from ama, the captain reached dispatch, and had the dispatch release amended to reflect the divert to ama. We had an uneventful approach, landing, and taxi into the gate. Once at the gate, we deplaned, had the MEL cleared, reboarded, and flew to lax. From my point of view, this event was a positive expression of CRM. The cockpit, cabin crew, ATC, and the second company aircraft all did a great job of communicating. The addition of ACARS would have made it easier for the captain to communication with dispatch at an earlier point in the event.

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Original NASA ASRS Text

Title: B737-300 CREW WAS DISPATCHED WITH THE R PACK MEL'ED INOP. THE L PACK FAILED IN ZKC CLASS A. THE CREW MADE AN EMER DSCNT, AND LANDED AT THE NEAREST SUITABLE ARPT.

Narrative: WE DEPARTED MCI OPERATING UNDER MEL FOR SINGLE PACK OP, THE R PACK INOP. PRIOR TO PAX ONLOAD, THE CAPT AND I DISCUSSED THE MEL WITH ONE ANOTHER AND INFORMED THE FLT ATTENDANTS OF THE SIT. AS IT WAS A VERY WARM DAY IN MCI, I SET THE PACK AT FULL COLD/AUTO. ONCE AT CRUISE ALT AND WITH A COMFORTABLE CABIN TEMP, I RESET THE PACK TO MID-RANGE. AT FL240 DURING CRUISE FLT, APPROX 135 NM N OF AMA, AND ABOUT 1 HR INTO THE FLT, THE L PACK TRIPPED OFF WITH AN ASSOCIATED CAUTION LIGHT. THE CABIN ALT BEGAN TO CLB AT A RAPID RATE. WE DONNED OUR OXYGEN MASKS, INITIATED A RAPID DSCNT TO 10000 FT MSL, AND INFORMED CTR OF OUR SIT. DURING THE DSCNT, THE CAPT INFORMED THE A FLT ATTENDANT OF THE SIT. THE MAX CABIN ALT REACHED WAS 10000 FT MSL, SO THE PAX OXYGEN MASKS DID NOT DEPLOY. WE RAN THE ASSOCIATED QRH CHKLISTS, BUT THE L PACK FAILED TO REMAIN OPERATIONAL. WE REQUESTED AND OBTAINED CLRNC TO AMA. ONCE HEADED TO AMA, THE CAPT PASSED CTLS OF THE ACFT TO ME AND ATTEMPTED TO ESTABLISH CONTACT WITH DISPATCH. AFTER SEVERAL UNSUCCESSFUL ATTEMPTS, THE CAPT REQUESTED ATC CONTACT AND INFORM COMPANY DISPATCH OF OUR SIT AND DIVERSION. THE CAPT ALSO SPOKE WITH ANOTHER COMPANY FLT AND REQUESTED THE OTHER FLT TO ATTEMPT TO CONTACT. ENRTE TO AMA, THE CAPT BRIEFED THE FLT ATTENDANTS OF THE SIT AND OUR PLAN OVER THE INTERCOM, THEN BRIEFED THE PAX OF THE SIT AND OUR PLAN. THE FLT ATTENDANTS REMAINED CALM AND PROFESSIONAL DURING THE EVENT, AND AS A RESULT, THE PAX REMAINED CALM. ABOUT 35 NM FROM AMA, THE CAPT REACHED DISPATCH, AND HAD THE DISPATCH RELEASE AMENDED TO REFLECT THE DIVERT TO AMA. WE HAD AN UNEVENTFUL APCH, LNDG, AND TAXI INTO THE GATE. ONCE AT THE GATE, WE DEPLANED, HAD THE MEL CLRED, REBOARDED, AND FLEW TO LAX. FROM MY POINT OF VIEW, THIS EVENT WAS A POSITIVE EXPRESSION OF CRM. THE COCKPIT, CABIN CREW, ATC, AND THE SECOND COMPANY ACFT ALL DID A GREAT JOB OF COMMUNICATING. THE ADDITION OF ACARS WOULD HAVE MADE IT EASIER FOR THE CAPT TO COM WITH DISPATCH AT AN EARLIER POINT IN THE EVENT.

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.