Narrative:

No established procedures for dispatchers; flight crews or maintenance addressing pressurization abnormals over high terrain. MEL does not address dispatching aircraft with obstacle limitations. Bottom line; flight must be able to be routed to safely transport passenger under 121 FARS. The aircraft abnormals need to be addressed to include safety of the passenger for the entire flight. Reported into dispatch for briefing for flight to sfo. Was advised about inoperative AC pack only after inquiring about the condition of the aircraft. Told aircraft is without the l-hand AC pack; 'oh you don't know.' I expressed concern about the use of this aircraft to fly this flight to the west coast reference obstacle clearance and drift-down and passenger oxygen requirements if second pack fails. Asked immediately if aircraft swap is available; ignored inquiry. I continued for the next 2+ hours building flight plan to satisfy far's and passenger safety requirements. After engaging in conversations with dispatch; duty officer; chief dispatcher and chief pilot; it was determined that we did need unpressurized drift-down routing. During the conversations there were multiple aircraft available with no mels that could have been used for this flight (2 packs operable). Those request were denied; with no explanation. Meanwhile; the crew prepared the aircraft for departure so we could leave once requirements were met. Our concerns include the operations control did not respond to our requests for a detailed flight plan to address the pressurization abnormal limitations. We stressed the need for the flight plan to include drift-down parameters for a loss of the single AC pack. Included in this flight plan; we repeatedly requested that the 30 passenger oxygen protection be included in the loss of pressurization drift-down calculation. Dispatch needed to manually calculate a 10000 ft flight plan to include alternates within a 30 min window. We became aware of previous other flts to the east and west coasts addressed this same issue and east coast flts were dispatched at 10000 ft. Additional time was wasted giving us 2 rtes that did not satisfy requirements. We caught the disparities and also noted the WX issue developing on the southern rtes. This forced a northerly route consideration.

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Original NASA ASRS Text

Title: B717 FLT CREW IS DISPATCHED WITH INOPERATIVE PACK. EXCESSIVE TIME WAS REQUIRED TO FLT PLAN FOR POSSIBLE DRIFT-DOWN OVER MOUNTAINOUS TERRAIN.

Narrative: NO ESTABLISHED PROCS FOR DISPATCHERS; FLT CREWS OR MAINT ADDRESSING PRESSURIZATION ABNORMALS OVER HIGH TERRAIN. MEL DOES NOT ADDRESS DISPATCHING ACFT WITH OBSTACLE LIMITATIONS. BOTTOM LINE; FLT MUST BE ABLE TO BE ROUTED TO SAFELY TRANSPORT PAX UNDER 121 FARS. THE ACFT ABNORMALS NEED TO BE ADDRESSED TO INCLUDE SAFETY OF THE PAX FOR THE ENTIRE FLT. RPTED INTO DISPATCH FOR BRIEFING FOR FLT TO SFO. WAS ADVISED ABOUT INOP AC PACK ONLY AFTER INQUIRING ABOUT THE CONDITION OF THE ACFT. TOLD ACFT IS WITHOUT THE L-HAND AC PACK; 'OH YOU DON'T KNOW.' I EXPRESSED CONCERN ABOUT THE USE OF THIS ACFT TO FLY THIS FLT TO THE WEST COAST REF OBSTACLE CLRNC AND DRIFT-DOWN AND PAX OXYGEN REQUIREMENTS IF SECOND PACK FAILS. ASKED IMMEDIATELY IF ACFT SWAP IS AVAILABLE; IGNORED INQUIRY. I CONTINUED FOR THE NEXT 2+ HRS BUILDING FLT PLAN TO SATISFY FAR'S AND PAX SAFETY REQUIREMENTS. AFTER ENGAGING IN CONVERSATIONS WITH DISPATCH; DUTY OFFICER; CHIEF DISPATCHER AND CHIEF PLT; IT WAS DETERMINED THAT WE DID NEED UNPRESSURIZED DRIFT-DOWN ROUTING. DURING THE CONVERSATIONS THERE WERE MULTIPLE ACFT AVAILABLE WITH NO MELS THAT COULD HAVE BEEN USED FOR THIS FLT (2 PACKS OPERABLE). THOSE REQUEST WERE DENIED; WITH NO EXPLANATION. MEANWHILE; THE CREW PREPARED THE ACFT FOR DEP SO WE COULD LEAVE ONCE REQUIREMENTS WERE MET. OUR CONCERNS INCLUDE THE OPS CTL DID NOT RESPOND TO OUR REQUESTS FOR A DETAILED FLT PLAN TO ADDRESS THE PRESSURIZATION ABNORMAL LIMITATIONS. WE STRESSED THE NEED FOR THE FLT PLAN TO INCLUDE DRIFT-DOWN PARAMETERS FOR A LOSS OF THE SINGLE AC PACK. INCLUDED IN THIS FLT PLAN; WE REPEATEDLY REQUESTED THAT THE 30 PAX OXYGEN PROTECTION BE INCLUDED IN THE LOSS OF PRESSURIZATION DRIFT-DOWN CALCULATION. DISPATCH NEEDED TO MANUALLY CALCULATE A 10000 FT FLT PLAN TO INCLUDE ALTERNATES WITHIN A 30 MIN WINDOW. WE BECAME AWARE OF PREVIOUS OTHER FLTS TO THE EAST AND WEST COASTS ADDRESSED THIS SAME ISSUE AND EAST COAST FLTS WERE DISPATCHED AT 10000 FT. ADDITIONAL TIME WAS WASTED GIVING US 2 RTES THAT DID NOT SATISFY REQUIREMENTS. WE CAUGHT THE DISPARITIES AND ALSO NOTED THE WX ISSUE DEVELOPING ON THE SOUTHERN RTES. THIS FORCED A NORTHERLY RTE CONSIDERATION.

Data retrieved from NASA's ASRS site as of January 2009 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.