Narrative:

Declared an emergency after loss of pressure (cabin) while climbing through 28000-35000 ft. Initiated descent to 10000 ft. En route from bdl to clt. Landed at lga at XA32. All 101 passenger and crew of 5 fine upon landing. Maintenance discovered a blown duct joint on right air conditioning system. No further problems resulted from this emergency as far as I know. Callback conversation with reporter revealed the following information: after detecting rapid cabin ascent, the DC9-30 flight crew declared an emergency and immediately initiated an emergency descent utilizing TCASII. Initial climb rate was 800-1000 FPM and cabin altitude never exceeded 10000 ft. The aircraft was approximately 40 mi north of lga and assigned only 1 intermediate altitude during descent on direct routing. At 10000 ft all operations were normal. Cabin attendant attendants had taken their seats (no flight deck/cabin crew communication took place). Captain gave PA regarding the rapid descent and aircraft status. ATC questioned aircraft crash fire rescue equipment requirements, and equipment (on standby status) followed aircraft to the gate after landing. FAA met the aircraft but no further action was taken. Maintenance found blown right air conditioning duct joint in the system.

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Original NASA ASRS Text

Title: A DC9-30 AIR CONDITIONING DUCT JOINT FAILED CAUSING AN EXCESSIVE CABIN CLB. EMER DECLARED FOLLOWED BY A DIVERSION.

Narrative: DECLARED AN EMER AFTER LOSS OF PRESSURE (CABIN) WHILE CLBING THROUGH 28000-35000 FT. INITIATED DSCNT TO 10000 FT. ENRTE FROM BDL TO CLT. LANDED AT LGA AT XA32. ALL 101 PAX AND CREW OF 5 FINE UPON LNDG. MAINT DISCOVERED A BLOWN DUCT JOINT ON R AIR CONDITIONING SYS. NO FURTHER PROBS RESULTED FROM THIS EMER AS FAR AS I KNOW. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: AFTER DETECTING RAPID CABIN ASCENT, THE DC9-30 FLC DECLARED AN EMER AND IMMEDIATELY INITIATED AN EMER DSCNT UTILIZING TCASII. INITIAL CLB RATE WAS 800-1000 FPM AND CABIN ALT NEVER EXCEEDED 10000 FT. THE ACFT WAS APPROX 40 MI N OF LGA AND ASSIGNED ONLY 1 INTERMEDIATE ALT DURING DSCNT ON DIRECT ROUTING. AT 10000 FT ALL OPS WERE NORMAL. CAB ATTENDANTS HAD TAKEN THEIR SEATS (NO FLT DECK/CABIN CREW COM TOOK PLACE). CAPT GAVE PA REGARDING THE RAPID DSCNT AND ACFT STATUS. ATC QUESTIONED ACFT CFR REQUIREMENTS, AND EQUIP (ON STANDBY STATUS) FOLLOWED ACFT TO THE GATE AFTER LNDG. FAA MET THE ACFT BUT NO FURTHER ACTION WAS TAKEN. MAINT FOUND BLOWN R AIR CONDITIONING DUCT JOINT IN THE SYS.

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.