Narrative:

I am writing this supplement to my NASA report as a detailed explanation of events that occurred on jan/fri/02. I am a captain with air carrier X and was assigned a trip, which originated out of ewr. The flight was flight abcd. The flight was being conducted on a B757-200. The routing was ewr to mdw and continuing on to sfo with the same cockpit crew. After arriving at the aircraft for the early morning departure, we started the APU and then after stabilization we turned on the aircraft air conditioning packs. The left pack failed to come on line. After turning the pack off switch off then on again, the left pack came on line. Preflight preparations were then completed. With all passenger boarded and departure time, we pushed back and started both engines. The left pack again failed to come on line and we again turned it off and then on. It once again came on line. I decided to 'write' the pack up in the maintenance logbook. The item was a 'crew deferrable' item and required a 'placard' which was to be added to the logbook and a 'sticker' was to be placed next to the left pack switch. This I failed to do. The failure of a pack to come on line is not routine but also not uncommon. With regards to the failure of the pack to initially come on line, I felt it was more of an annoyance than a problem. After takeoff and while en route to mdw, I contacted air carrier X maintenance and informed them that I had a 'write-up' that would require corrective action upon arrival in mdw. The left pack operated normally for the duration of the flight. Upon our arrival in mdw, maintenance did remove the maintenance log and attempted to locate the left pack's problem. They were unable to find the problem before the next departure and subsequently 'deferred' the left pack. Prior to departure, dispatch issued a revised flight plan reflecting the different routing and altitude requirements to satisfy the maximum altitude of FL350 and a routing that would enable the aircraft to maintain a maximum altitude of 14000 ft in the event the remaining pack was lost. The revised routing added approximately 50 mins to the flying time and 200 additional mi. After departing mdw and while en route, and with the knowledge that the left pack was operating normally, and had been doing so since our original departure from ewr and the additional time and mileage and a functioning pack in mind, I requested a more direct routing and a climb to FL390. I called dispatch and informed them of my intention. After several mins, I received a call from company dispatch and they informed me that they were recommending I descend to FL350 and return to the recommended routing. Per their request, I told them I would immediately comply, and did so.

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Original NASA ASRS Text

Title: B757-200 CAPT IGNORED MEL OPERATING RESTRS REGARDING INOP PACK.

Narrative: I AM WRITING THIS SUPPLEMENT TO MY NASA RPT AS A DETAILED EXPLANATION OF EVENTS THAT OCCURRED ON JAN/FRI/02. I AM A CAPT WITH ACR X AND WAS ASSIGNED A TRIP, WHICH ORIGINATED OUT OF EWR. THE FLT WAS FLT ABCD. THE FLT WAS BEING CONDUCTED ON A B757-200. THE ROUTING WAS EWR TO MDW AND CONTINUING ON TO SFO WITH THE SAME COCKPIT CREW. AFTER ARRIVING AT THE ACFT FOR THE EARLY MORNING DEP, WE STARTED THE APU AND THEN AFTER STABILIZATION WE TURNED ON THE ACFT AIR CONDITIONING PACKS. THE L PACK FAILED TO COME ON LINE. AFTER TURNING THE PACK OFF SWITCH OFF THEN ON AGAIN, THE L PACK CAME ON LINE. PREFLT PREPARATIONS WERE THEN COMPLETED. WITH ALL PAX BOARDED AND DEP TIME, WE PUSHED BACK AND STARTED BOTH ENGS. THE L PACK AGAIN FAILED TO COME ON LINE AND WE AGAIN TURNED IT OFF AND THEN ON. IT ONCE AGAIN CAME ON LINE. I DECIDED TO 'WRITE' THE PACK UP IN THE MAINT LOGBOOK. THE ITEM WAS A 'CREW DEFERRABLE' ITEM AND REQUIRED A 'PLACARD' WHICH WAS TO BE ADDED TO THE LOGBOOK AND A 'STICKER' WAS TO BE PLACED NEXT TO THE L PACK SWITCH. THIS I FAILED TO DO. THE FAILURE OF A PACK TO COME ON LINE IS NOT ROUTINE BUT ALSO NOT UNCOMMON. WITH REGARDS TO THE FAILURE OF THE PACK TO INITIALLY COME ON LINE, I FELT IT WAS MORE OF AN ANNOYANCE THAN A PROB. AFTER TKOF AND WHILE ENRTE TO MDW, I CONTACTED ACR X MAINT AND INFORMED THEM THAT I HAD A 'WRITE-UP' THAT WOULD REQUIRE CORRECTIVE ACTION UPON ARR IN MDW. THE L PACK OPERATED NORMALLY FOR THE DURATION OF THE FLT. UPON OUR ARR IN MDW, MAINT DID REMOVE THE MAINT LOG AND ATTEMPTED TO LOCATE THE L PACK'S PROB. THEY WERE UNABLE TO FIND THE PROB BEFORE THE NEXT DEP AND SUBSEQUENTLY 'DEFERRED' THE L PACK. PRIOR TO DEP, DISPATCH ISSUED A REVISED FLT PLAN REFLECTING THE DIFFERENT ROUTING AND ALT REQUIREMENTS TO SATISFY THE MAX ALT OF FL350 AND A ROUTING THAT WOULD ENABLE THE ACFT TO MAINTAIN A MAX ALT OF 14000 FT IN THE EVENT THE REMAINING PACK WAS LOST. THE REVISED ROUTING ADDED APPROX 50 MINS TO THE FLYING TIME AND 200 ADDITIONAL MI. AFTER DEPARTING MDW AND WHILE ENRTE, AND WITH THE KNOWLEDGE THAT THE L PACK WAS OPERATING NORMALLY, AND HAD BEEN DOING SO SINCE OUR ORIGINAL DEP FROM EWR AND THE ADDITIONAL TIME AND MILEAGE AND A FUNCTIONING PACK IN MIND, I REQUESTED A MORE DIRECT ROUTING AND A CLB TO FL390. I CALLED DISPATCH AND INFORMED THEM OF MY INTENTION. AFTER SEVERAL MINS, I RECEIVED A CALL FROM COMPANY DISPATCH AND THEY INFORMED ME THAT THEY WERE RECOMMENDING I DSND TO FL350 AND RETURN TO THE RECOMMENDED ROUTING. PER THEIR REQUEST, I TOLD THEM I WOULD IMMEDIATELY COMPLY, AND DID SO.

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.