Narrative:

There was a crack discovered in the right air conditioning pack during routine scheduled maintenance. In this case, the coalescer bags were being changed. This duct is located downstream (after) the right pack flow control valve. I decided the pack could be deferred under MEL 21-1 as inoperative. The duct then remains unpressurized and the aircraft is dispatched safely. I planned on replacing the duct during the ZZZ turn. 4 legs later I did not wish to fly the aircraft long without a pack due to altitude limits. I do not have a problem with this, however, even though other carrier's do have relief, aircraft X does not. In the future, I will not defer air conditioning packs for a cracked duct.

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Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED WITH A CRACK IN AN AIR CONDITIONING DUCT DOWNSTREAM OF THE FLOW CTL VALVE. CRACK DEFERRED PER THE MEL AS INOP.

Narrative: THERE WAS A CRACK DISCOVERED IN THE R AIR CONDITIONING PACK DURING ROUTINE SCHEDULED MAINT. IN THIS CASE, THE COALESCER BAGS WERE BEING CHANGED. THIS DUCT IS LOCATED DOWNSTREAM (AFTER) THE R PACK FLOW CTL VALVE. I DECIDED THE PACK COULD BE DEFERRED UNDER MEL 21-1 AS INOP. THE DUCT THEN REMAINS UNPRESSURIZED AND THE ACFT IS DISPATCHED SAFELY. I PLANNED ON REPLACING THE DUCT DURING THE ZZZ TURN. 4 LEGS LATER I DID NOT WISH TO FLY THE ACFT LONG WITHOUT A PACK DUE TO ALT LIMITS. I DO NOT HAVE A PROB WITH THIS, HOWEVER, EVEN THOUGH OTHER CARRIER'S DO HAVE RELIEF, ACFT X DOES NOT. IN THE FUTURE, I WILL NOT DEFER AIR CONDITIONING PACKS FOR A CRACKED DUCT.

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.