Narrative:

En route at FL350 on a flight from edmonton, canada, to anc, ak, both air conditioning packs failed with the temperature selectors in 'automatic.' prior to this, the cockpit was excessively cold, potentially interfering with our duties. The captain, who was the PNF, consulted the appropriate abnormal for this. He then selected 'manual' as 'automatic' would not keep us warm enough. As the duct temperature approached approximately 80 degrees C (180 degree F) he reselected 'automatic.' within approximately 5 mins the packs failed indicating 0 pressure. The cabin slowly started to climb at this time. As a precautionary measure, the captain ordered we both put on our oxygen masks and he requested a lower altitude from ATC, and also advising them of our situation. Terrain and traffic being a consideration, we were assigned 10000 ft. As we started to descend, the cabin began to climb rapidly. The captain took over PF duties and commanded the rapid depressurization, emergency descent, and descent checklists. Once at 10000 ft, we considered our fuel status and position. Then we performed the appropriate abnormal for the problem without success. At this time we decided to declare an emergency as a precautionary measure. We then discussed options with ATC, dispatch, maintenance, and the chief pilot's office. Upon mutual agreement, we then proceeded to cordova, ak (smith field). Upon completing confirmation of the appropriate performance landing data and WX, we landed in cordova, ak, without further incident.

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Original NASA ASRS Text

Title: FLC OF A DC9-41 CARGO DECLARED AN EMER AFTER BEING UNABLE TO KEEP THE CABIN ALT FROM RISING WHEN BOTH ENG PRESSURIZATION PACKS WERE ON. CAPT THEN TOOK ACFT CTL AND MADE AN EMER DSCNT TO 10000 FT AND DIVERTED TO LAND BEFORE THE CREW BECAME MORE UNCOMFORTABLE WITH THE COCKPIT COLD TEMP.

Narrative: ENRTE AT FL350 ON A FLT FROM EDMONTON, CANADA, TO ANC, AK, BOTH AIR CONDITIONING PACKS FAILED WITH THE TEMP SELECTORS IN 'AUTO.' PRIOR TO THIS, THE COCKPIT WAS EXCESSIVELY COLD, POTENTIALLY INTERFERING WITH OUR DUTIES. THE CAPT, WHO WAS THE PNF, CONSULTED THE APPROPRIATE ABNORMAL FOR THIS. HE THEN SELECTED 'MANUAL' AS 'AUTO' WOULD NOT KEEP US WARM ENOUGH. AS THE DUCT TEMP APCHED APPROX 80 DEGS C (180 DEG F) HE RESELECTED 'AUTO.' WITHIN APPROX 5 MINS THE PACKS FAILED INDICATING 0 PRESSURE. THE CABIN SLOWLY STARTED TO CLB AT THIS TIME. AS A PRECAUTIONARY MEASURE, THE CAPT ORDERED WE BOTH PUT ON OUR OXYGEN MASKS AND HE REQUESTED A LOWER ALT FROM ATC, AND ALSO ADVISING THEM OF OUR SIT. TERRAIN AND TFC BEING A CONSIDERATION, WE WERE ASSIGNED 10000 FT. AS WE STARTED TO DSND, THE CABIN BEGAN TO CLB RAPIDLY. THE CAPT TOOK OVER PF DUTIES AND COMMANDED THE RAPID DEPRESSURIZATION, EMER DSCNT, AND DSCNT CHKLISTS. ONCE AT 10000 FT, WE CONSIDERED OUR FUEL STATUS AND POS. THEN WE PERFORMED THE APPROPRIATE ABNORMAL FOR THE PROB WITHOUT SUCCESS. AT THIS TIME WE DECIDED TO DECLARE AN EMER AS A PRECAUTIONARY MEASURE. WE THEN DISCUSSED OPTIONS WITH ATC, DISPATCH, MAINT, AND THE CHIEF PLT'S OFFICE. UPON MUTUAL AGREEMENT, WE THEN PROCEEDED TO CORDOVA, AK (SMITH FIELD). UPON COMPLETING CONFIRMATION OF THE APPROPRIATE PERFORMANCE LNDG DATA AND WX, WE LANDED IN CORDOVA, AK, WITHOUT FURTHER INCIDENT.

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.