An MD80 flight crew experienced loss of cabin pressure on climbout. They ran the checklist; declared...

Attributes
ACN	802945
Time
Date	200808
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : zzz.vor
State Reference	US
Altitude	msl single value : 10000
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	artcc : zzz.artcc
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	802945
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

After climbing and nearing the ZZZ VOR on the departure; we were asked to expedite our climb through 13000 ft on our way to 15000 ft. Being pretty heavy; we said we would do our best and maintained roughly 250 KTS to comply. At that time; we noticed our ears starting to slowly pop and immediately checked the pack units and associated indicators. There was very low flow and the pressurization flow light then illuminated. We also noticed the pressurization differential becoming lower and the cabin altitude needle very slowly increasing. We observed the outflow valve indicator near or fully closed and chose to run the cabin altitude warning/rapid depressurization checklist to manually close the outflow valve as well as verify switch and indicator position in the pressurization system. All switches were normal with packs in automatic. We then ran the pressurization flow checklist to comply with the amber light indication and ensure AC supply switches were in automatic. We immediately notified ATC and asked for a lower altitude below 10000 ft and an emergency clearance back to ZZZ to land. The approach and landing back into ZZZ was uneventful.

Original NASA ASRS Text

Title: AN MD80 FLT CREW EXPERIENCED LOSS OF CABIN PRESSURE ON CLIMBOUT. THEY RAN THE CHECKLIST; DECLARED AN EMERGENCY; AND RETURNED TO THEIR DEP ARPT.

Narrative: AFTER CLBING AND NEARING THE ZZZ VOR ON THE DEP; WE WERE ASKED TO EXPEDITE OUR CLB THROUGH 13000 FT ON OUR WAY TO 15000 FT. BEING PRETTY HVY; WE SAID WE WOULD DO OUR BEST AND MAINTAINED ROUGHLY 250 KTS TO COMPLY. AT THAT TIME; WE NOTICED OUR EARS STARTING TO SLOWLY POP AND IMMEDIATELY CHKED THE PACK UNITS AND ASSOCIATED INDICATORS. THERE WAS VERY LOW FLOW AND THE PRESSURIZATION FLOW LIGHT THEN ILLUMINATED. WE ALSO NOTICED THE PRESSURIZATION DIFFERENTIAL BECOMING LOWER AND THE CABIN ALT NEEDLE VERY SLOWLY INCREASING. WE OBSERVED THE OUTFLOW VALVE INDICATOR NEAR OR FULLY CLOSED AND CHOSE TO RUN THE CABIN ALT WARNING/RAPID DEPRESSURIZATION CHKLIST TO MANUALLY CLOSE THE OUTFLOW VALVE AS WELL AS VERIFY SWITCH AND INDICATOR POS IN THE PRESSURIZATION SYS. ALL SWITCHES WERE NORMAL WITH PACKS IN AUTO. WE THEN RAN THE PRESSURIZATION FLOW CHKLIST TO COMPLY WITH THE AMBER LIGHT INDICATION AND ENSURE AC SUPPLY SWITCHES WERE IN AUTO. WE IMMEDIATELY NOTIFIED ATC AND ASKED FOR A LOWER ALT BELOW 10000 FT AND AN EMER CLRNC BACK TO ZZZ TO LAND. THE APCH AND LNDG BACK INTO ZZZ WAS UNEVENTFUL.

Data retrieved from NASA's ASRS site as of May 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.

An MD80 flight crew experienced loss of cabin pressure on climbout. They ran the checklist; declared an emergency; and returned to their departure airport.