DC9 crew lost cabin pressurization in ZAU class a airspace.

Attributes
ACN	493230
Time
Date	200011
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : obk.vor
State Reference	IL
Altitude	msl single value : 33000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau.artcc
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 9500 flight time type : 6000
ASRS Report	493230
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 190 flight time total : 10000 flight time type : 1000
ASRS Report	492696
Events
Anomaly	aircraft equipment problem : critical other anomaly
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : provided flight assist controller : issued new clearance flight crew : declared emergency flight crew : diverted to another airport flight crew : landed in emergency condition
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

We had a rapid decompression at FL330. It appears that our right pack failed at altitude. We discovered it when the cabin altitude was at 8000 ft and rapidly increasing. An emergency was declared and the aircraft was turned towards ord for an uneventful landing. Incidentally, 1/2 way through the descent the flight attendants advised us there was smoke in the cabin. We initiated our 'smoke in the cabin' procedures, but subsequently realized the problem was caused by the oxygen generators. My first thought was air conditioning pack fire, but our lead refocused me when she suggested the oxygen generators. Supplemental information from acn 492696: air carrier flight abc, msp-cmh. Cruise flight at FL330. The lead flight attendant came to the cockpit and said it was cold in the cabin. I made an adjustment on the right temperature control. Immediately after adjustment was made, the cabin began to climb. The captain initiated an emergency descent. We ran the appropriate checklists and were unable to regain pressurization. We diverted to ord and landed without incident.

Original NASA ASRS Text

Title: DC9 CREW LOST CABIN PRESSURIZATION IN ZAU CLASS A AIRSPACE.

Narrative: WE HAD A RAPID DECOMPRESSION AT FL330. IT APPEARS THAT OUR R PACK FAILED AT ALT. WE DISCOVERED IT WHEN THE CABIN ALT WAS AT 8000 FT AND RAPIDLY INCREASING. AN EMER WAS DECLARED AND THE ACFT WAS TURNED TOWARDS ORD FOR AN UNEVENTFUL LNDG. INCIDENTALLY, 1/2 WAY THROUGH THE DSCNT THE FLT ATTENDANTS ADVISED US THERE WAS SMOKE IN THE CABIN. WE INITIATED OUR 'SMOKE IN THE CABIN' PROCS, BUT SUBSEQUENTLY REALIZED THE PROB WAS CAUSED BY THE OXYGEN GENERATORS. MY FIRST THOUGHT WAS AIR CONDITIONING PACK FIRE, BUT OUR LEAD REFOCUSED ME WHEN SHE SUGGESTED THE OXYGEN GENERATORS. SUPPLEMENTAL INFO FROM ACN 492696: ACR FLT ABC, MSP-CMH. CRUISE FLT AT FL330. THE LEAD FLT ATTENDANT CAME TO THE COCKPIT AND SAID IT WAS COLD IN THE CABIN. I MADE AN ADJUSTMENT ON THE R TEMP CTL. IMMEDIATELY AFTER ADJUSTMENT WAS MADE, THE CABIN BEGAN TO CLB. THE CAPT INITIATED AN EMER DSCNT. WE RAN THE APPROPRIATE CHKLISTS AND WERE UNABLE TO REGAIN PRESSURIZATION. WE DIVERTED TO ORD AND LANDED WITHOUT INCIDENT.

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.