Narrative:

I originated air carrier X flight abcd bos-phl on apr/mon/01. The aircraft X airbus 320 had the #1 pack MEL fault inoperative. The logbook write-up had been done by a mechanic some time during the remain overnight phase. Historically, the airbus 319/320 has repeatedly had tendencies to be slow to initially respond when bleed air is applied, thereby displaying nuisance fault lights. At times, the pack fault cannot be rectified until engine bleed air is applied. With these pack tendencies in mind, I tried the #1 pack, got good indications, and reported this to my dispatcher via commercial radio. I received a message back from dispatch with a thanks and maintenance would be advised. I felt this information should be relayed prior to our departure so as much heads up time as possible would be available because I knew that this aircraft was scheduled to fly phl-sdq-phl. That flight routing would be better if it had maximum altitude capability. Flight abcd bos-phl was conducted at maximum cruise altitude of FL260 and no problems were noted. Upon arrival in phl, I told the mechanic who met the flight that the #1 pack seemed to be ok. (The following information was relayed to me by the captain who flew aircraft X from phl-sdq-phl.) apparently, the #1 pack was removed from MEL status, but some valve in the system had been hardwired in position by the bos mechanic during the remain overnight phase when the pack was initially placed on MEL status. When the pack was removed from MEL status in phl, the previously hardwired valve was not 'un-hardwired.' apparently, the aircraft incurred pressurization problems on the return flight sdq-phl. It was upon arrival in phl that the hardwired valve problem was discovered.

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Original NASA ASRS Text

Title: AN A320 PIC RPT OF A MAINT PROC THAT WAS IGNORED CREATING AN ACFT PRESSURIZATION PROB FOR A LATER FLT INTO PHL, PA.

Narrative: I ORIGINATED ACR X FLT ABCD BOS-PHL ON APR/MON/01. THE ACFT X AIRBUS 320 HAD THE #1 PACK MEL FAULT INOP. THE LOGBOOK WRITE-UP HAD BEEN DONE BY A MECH SOME TIME DURING THE REMAIN OVERNIGHT PHASE. HISTORICALLY, THE AIRBUS 319/320 HAS REPEATEDLY HAD TENDENCIES TO BE SLOW TO INITIALLY RESPOND WHEN BLEED AIR IS APPLIED, THEREBY DISPLAYING NUISANCE FAULT LIGHTS. AT TIMES, THE PACK FAULT CANNOT BE RECTIFIED UNTIL ENG BLEED AIR IS APPLIED. WITH THESE PACK TENDENCIES IN MIND, I TRIED THE #1 PACK, GOT GOOD INDICATIONS, AND RPTED THIS TO MY DISPATCHER VIA COMMERCIAL RADIO. I RECEIVED A MESSAGE BACK FROM DISPATCH WITH A THANKS AND MAINT WOULD BE ADVISED. I FELT THIS INFO SHOULD BE RELAYED PRIOR TO OUR DEP SO AS MUCH HEADS UP TIME AS POSSIBLE WOULD BE AVAILABLE BECAUSE I KNEW THAT THIS ACFT WAS SCHEDULED TO FLY PHL-SDQ-PHL. THAT FLT ROUTING WOULD BE BETTER IF IT HAD MAX ALT CAPABILITY. FLT ABCD BOS-PHL WAS CONDUCTED AT MAX CRUISE ALT OF FL260 AND NO PROBS WERE NOTED. UPON ARR IN PHL, I TOLD THE MECH WHO MET THE FLT THAT THE #1 PACK SEEMED TO BE OK. (THE FOLLOWING INFO WAS RELAYED TO ME BY THE CAPT WHO FLEW ACFT X FROM PHL-SDQ-PHL.) APPARENTLY, THE #1 PACK WAS REMOVED FROM MEL STATUS, BUT SOME VALVE IN THE SYS HAD BEEN HARDWIRED IN POS BY THE BOS MECH DURING THE REMAIN OVERNIGHT PHASE WHEN THE PACK WAS INITIALLY PLACED ON MEL STATUS. WHEN THE PACK WAS REMOVED FROM MEL STATUS IN PHL, THE PREVIOUSLY HARDWIRED VALVE WAS NOT 'UN-HARDWIRED.' APPARENTLY, THE ACFT INCURRED PRESSURIZATION PROBS ON THE RETURN FLT SDQ-PHL. IT WAS UPON ARR IN PHL THAT THE HARDWIRED VALVE PROB WAS DISCOVERED.

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.