An MD80 flight crew experienced a cabin altitude warning light and excessive cabin altitude. They de...

Attributes
ACN	786816
Time
Date	200805
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : zzz.vortac
State Reference	US
Altitude	msl single value : 30000
Environment
Weather Elements	Thunderstorm
Light	Daylight
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
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	786816
Events
Anomaly	aircraft equipment problem : critical non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : cabin alt warning light other flight crewa
Resolutory Action	flight crew : exited adverse environment flight crew : overcame equipment problem flight crew : declared emergency
Consequence	other other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Taxi/takeoff/climb uneventful. Passing through 17000 ft; received direct to ZZZ; took a heading change due to thunderstorms. Checked pressurization on climb check -- read properly. Going in and out of clouds and noticed ram air temperature at 5 degrees C around FL200. Put on engine and wing anti-ice. Checked WX radar and getting navigation set up for direct mlc when cabin altitude warning light came on at FL300. Checked packs -- both on with low flow. Cabin altitude read 9000 ft; cabin read 300 ft rise. No icing noted on wiper blade pin. Had no pressurization flow light or any other lights. Requested descent from center. Started descent to FL240; then center gave us FL190. Declared an emergency and accomplished the immediate action items. Cabin altitude rose to 11500 ft. Pressure stopped rising after accomplishing immediate action items. Accomplished rest of the checklist except for deploying the passenger's masks (altitude below 14000 ft with cabin reading 7000 ft by this time). Packs started working fine after leveling off at 10000 ft. Captain gave me the aircraft since he had an ear block. Landed at ZZZ without incident. Taxied to gate and debriefed maintenance personnel. Aircraft taken OTS. All 3 flight attendants and I were fine. Captain had to take himself off the trip due to his ear.

Original NASA ASRS Text

Title: AN MD80 FLT CREW EXPERIENCED A CABIN ALT WARNING LIGHT AND EXCESSIVE CABIN ALT. THEY DECLARED AN EMERGENCY AND EXECUTED AN EMERGENCY DESCENT; REGAINING NORMAL PACK OPERATION AT 10000 FT.

Narrative: TAXI/TKOF/CLB UNEVENTFUL. PASSING THROUGH 17000 FT; RECEIVED DIRECT TO ZZZ; TOOK A HDG CHANGE DUE TO TSTMS. CHKED PRESSURIZATION ON CLB CHK -- READ PROPERLY. GOING IN AND OUT OF CLOUDS AND NOTICED RAM AIR TEMP AT 5 DEGS C AROUND FL200. PUT ON ENG AND WING ANTI-ICE. CHKED WX RADAR AND GETTING NAV SET UP FOR DIRECT MLC WHEN CABIN ALT WARNING LIGHT CAME ON AT FL300. CHKED PACKS -- BOTH ON WITH LOW FLOW. CABIN ALT READ 9000 FT; CABIN READ 300 FT RISE. NO ICING NOTED ON WIPER BLADE PIN. HAD NO PRESSURIZATION FLOW LIGHT OR ANY OTHER LIGHTS. REQUESTED DSCNT FROM CTR. STARTED DSCNT TO FL240; THEN CTR GAVE US FL190. DECLARED AN EMER AND ACCOMPLISHED THE IMMEDIATE ACTION ITEMS. CABIN ALT ROSE TO 11500 FT. PRESSURE STOPPED RISING AFTER ACCOMPLISHING IMMEDIATE ACTION ITEMS. ACCOMPLISHED REST OF THE CHKLIST EXCEPT FOR DEPLOYING THE PAX'S MASKS (ALT BELOW 14000 FT WITH CABIN READING 7000 FT BY THIS TIME). PACKS STARTED WORKING FINE AFTER LEVELING OFF AT 10000 FT. CAPT GAVE ME THE ACFT SINCE HE HAD AN EAR BLOCK. LANDED AT ZZZ WITHOUT INCIDENT. TAXIED TO GATE AND DEBRIEFED MAINT PERSONNEL. ACFT TAKEN OTS. ALL 3 FLT ATTENDANTS AND I WERE FINE. CAPT HAD TO TAKE HIMSELF OFF THE TRIP DUE TO HIS EAR.

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 a cabin altitude warning light and excessive cabin altitude. They declared an emergency and executed an emergency descent; regaining normal pack operation at 10000 ft.