Narrative:

The #3 air conditioning pack was squawked as being unable to pressurize aircraft by itself per normal operating procedures. I then placarded the #3 pack inoperative per MEL reference #21-01 (attached sheets). The second write-up stated that the #2 pack airflow was stuck in low. I then placarded the #2 pack flow control valve inoperative per military reference #21-05 (attached sheets) on the recommendation of tulsa tech rep and tech crew chief. After rereading the MEL reference #21-05, I feel that the aircraft could have misplacarded and possibly should also have the #2 pack placarded under reference #21-01 instead of 21.05. I am still unclear as to the legality of placarding the #2 pack placarded under 21-05 with the #3 pack already placarded under 21-01. Dispatch did load 7000 pounds additional fuel on board and restr the aircraft to a maximum altitude of FL250, as in reference# 21-01. However, the #2 pack was still placarded under 21-05. The aircraft flew 1 leg to lax where mechanics replaced the #2 pack flow control valve, thus removing the deviation reference #21-05. I felt that reference #21-05 was unclear in this situation. The pack works but airflow appeared to be low. It was still able to pressurize as per the item pertaining to the #2 pack (attached sheets). Next time, since dispatch restr the aircraft to FL250 anyway, I would save myself all this confusion by placarding under 21-01 instead of 21-05. I feel the 21-05 was unclear in this situation.

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Original NASA ASRS Text

Title: WDB DISPATCHED WITH 1 AIR CONDITIONING PACK INOPERATIVE AND THE AIRFLOW CTL VALVE OF ANOTHER STUCK IN LOW.

Narrative: THE #3 AIR CONDITIONING PACK WAS SQUAWKED AS BEING UNABLE TO PRESSURIZE ACFT BY ITSELF PER NORMAL OPERATING PROCS. I THEN PLACARDED THE #3 PACK INOP PER MEL REF #21-01 (ATTACHED SHEETS). THE SECOND WRITE-UP STATED THAT THE #2 PACK AIRFLOW WAS STUCK IN LOW. I THEN PLACARDED THE #2 PACK FLOW CTL VALVE INOP PER MIL REF #21-05 (ATTACHED SHEETS) ON THE RECOMMENDATION OF TULSA TECH REP AND TECH CREW CHIEF. AFTER REREADING THE MEL REF #21-05, I FEEL THAT THE ACFT COULD HAVE MISPLACARDED AND POSSIBLY SHOULD ALSO HAVE THE #2 PACK PLACARDED UNDER REF #21-01 INSTEAD OF 21.05. I AM STILL UNCLEAR AS TO THE LEGALITY OF PLACARDING THE #2 PACK PLACARDED UNDER 21-05 WITH THE #3 PACK ALREADY PLACARDED UNDER 21-01. DISPATCH DID LOAD 7000 LBS ADDITIONAL FUEL ON BOARD AND RESTR THE ACFT TO A MAX ALT OF FL250, AS IN REF# 21-01. HOWEVER, THE #2 PACK WAS STILL PLACARDED UNDER 21-05. THE ACFT FLEW 1 LEG TO LAX WHERE MECHS REPLACED THE #2 PACK FLOW CTL VALVE, THUS REMOVING THE DEVIATION REF #21-05. I FELT THAT REF #21-05 WAS UNCLEAR IN THIS SITUATION. THE PACK WORKS BUT AIRFLOW APPEARED TO BE LOW. IT WAS STILL ABLE TO PRESSURIZE AS PER THE ITEM PERTAINING TO THE #2 PACK (ATTACHED SHEETS). NEXT TIME, SINCE DISPATCH RESTR THE ACFT TO FL250 ANYWAY, I WOULD SAVE MYSELF ALL THIS CONFUSION BY PLACARDING UNDER 21-01 INSTEAD OF 21-05. I FEEL THE 21-05 WAS UNCLEAR IN THIS SITUATION.

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.