Narrative:

As we were cleared to climb to 17000 ft and crossing 10000 ft, the legend 'cabin pressurization' and the alarm came on the EICAS. At that point, I realized that both air conditioning packs were off, due to the fact that we took off intentionally with them off as usual and that I did not connect them at 400 ft and 1000 ft as established, for I was kind of busy on the radio. I immediately switched them to on. Punched altitude hold, and manually tried to lower the cabin altitude but instead I wrongly increased it and the oxygen masks fell. I immediately reconsidered and lowered it again speaking to the passenger that there was nothing to worry about, that the aircraft was handling perfectly and that we had a wrong signal to the oxygen system that let the masks drop. Also, I requested clearance from ATC to climb with a minimum rate and that we would advise when ready to climb normally and so we did. The flight attendants informed me that approximately 15 masks were pulled and activated by some passenger. I told that to please relocate the ones that were not used and to wait 30 mins to relocate the ones that were used. My decision was taken because there were no prior reports of pressurization malfunction and that both air conditioning packs were handling perfectly. We do not have thrust power settings established for takeoff with air conditioning system on. We usually erase the EICAS announcements that are normal, so at takeoff we can detect any malfunction (in the future I may leave specifically the air condition announcements on, or punch recall after selecting gear up).

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Original NASA ASRS Text

Title: B757 CREW FAILS TO TURN ON PACKS AFTER A 'PACKS OFF' TKOF. CABIN ALT RISES AND OXYGEN MASKS FALL. FLT CONTINUES AFTER RECOVERY OF CABIN ALT CTL.

Narrative: AS WE WERE CLRED TO CLB TO 17000 FT AND XING 10000 FT, THE LEGEND 'CABIN PRESSURIZATION' AND THE ALARM CAME ON THE EICAS. AT THAT POINT, I REALIZED THAT BOTH AIR CONDITIONING PACKS WERE OFF, DUE TO THE FACT THAT WE TOOK OFF INTENTIONALLY WITH THEM OFF AS USUAL AND THAT I DID NOT CONNECT THEM AT 400 FT AND 1000 FT AS ESTABLISHED, FOR I WAS KIND OF BUSY ON THE RADIO. I IMMEDIATELY SWITCHED THEM TO ON. PUNCHED ALT HOLD, AND MANUALLY TRIED TO LOWER THE CABIN ALT BUT INSTEAD I WRONGLY INCREASED IT AND THE OXYGEN MASKS FELL. I IMMEDIATELY RECONSIDERED AND LOWERED IT AGAIN SPEAKING TO THE PAX THAT THERE WAS NOTHING TO WORRY ABOUT, THAT THE ACFT WAS HANDLING PERFECTLY AND THAT WE HAD A WRONG SIGNAL TO THE OXYGEN SYS THAT LET THE MASKS DROP. ALSO, I REQUESTED CLRNC FROM ATC TO CLB WITH A MINIMUM RATE AND THAT WE WOULD ADVISE WHEN READY TO CLB NORMALLY AND SO WE DID. THE FLT ATTENDANTS INFORMED ME THAT APPROX 15 MASKS WERE PULLED AND ACTIVATED BY SOME PAX. I TOLD THAT TO PLEASE RELOCATE THE ONES THAT WERE NOT USED AND TO WAIT 30 MINS TO RELOCATE THE ONES THAT WERE USED. MY DECISION WAS TAKEN BECAUSE THERE WERE NO PRIOR RPTS OF PRESSURIZATION MALFUNCTION AND THAT BOTH AIR CONDITIONING PACKS WERE HANDLING PERFECTLY. WE DO NOT HAVE THRUST PWR SETTINGS ESTABLISHED FOR TKOF WITH AIR CONDITIONING SYS ON. WE USUALLY ERASE THE EICAS ANNOUNCEMENTS THAT ARE NORMAL, SO AT TKOF WE CAN DETECT ANY MALFUNCTION (IN THE FUTURE I MAY LEAVE SPECIFICALLY THE AIR CONDITION ANNOUNCEMENTS ON, OR PUNCH RECALL AFTER SELECTING GEAR UP).

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.