B757 FLT CREW REPORTS CABIN ALTITUDE WARNING AT FL350 AND EMERGENCY DESCENT. ACFT DISPATCHED SINGLE PACK AND MEL'ED PACK IS USED DURING DESCENT TO POSITIVE EFFECT.

Narrative

LEVEL AT FL350; EICAS CABIN ALT WARNING ACTIVATED. (THE L PACK WAS ON MEL.) ALL R PACK INDICATIONS WERE NORMAL EXCEPT THAT THE CABIN ALT WAS INCREASING THROUGH 11000 FT. THE EXCESSIVE CABIN ALT/RAPID DEPRESSURIZATION PROC WAS INITIATED AND COMPLETED. AN EMER WAS DECLARED WITH ATC. DURING THE DSCNT; UNDER THE PROVISIONS OF MY EMER AUTH; I ELECTED TO ACTIVATE THE MEL'ED L PACK IN ORDER TO REGAIN CTL OF THE CABIN ALT. THE CABIN ALT BECAME CTLABLE AND THE EICAS CABIN ALT WARNING EXTINGUISHED. THE ACFT WAS LEVELED AT 10000 FT MSL. I CHKED WITH THE FLT ATTENDANTS AND THERE WERE NO FLT ATTENDANT OR PAX ISSUES. THE OXYGEN MASKS DID NOT DEPLOY. I PROCEEDED TO COORD WITH DISPATCH AND MAINT CTL. BASED ON THE FUEL ON BOARD; WX AND THE CTLABILITY OF THE CABIN ALT; A DECISION WAS MADE TO CONTINUE TO ZZZ. I MADE AN ANNOUNCEMENT TO THE PAX REGARDING OUR SITUATION. THE REMAINDER OF THE FLT WAS UNEVENTFUL. UPON ARR; I MADE AN APPROPRIATE LOGBOOK ENTRY. FLT CREW CAUSE/NARRATIVE: UNKNOWN. FLT CREW SUGGESTIONS/NARRATIVE: THIS WAS THE FIRST TIME I HAVE ACCOMPLISHED AN ACTUAL EMER DSCNT IN AN ACFT. FOR YRS IN THE SIMULATOR; I HAVE BEEN PUTTING MY HEADSET BACK ON MY HEAD AFTER I DON THE OXYGEN MASK. I USED THIS TECHNIQUE IN THE ACFT AND IT MADE COMMUNICATING WITH ATC AND ALSO THE FO MANY TIMES THE CLARITY OF TRYING TO USE THE FLT DECK SPEAKERS.