Air carrier medium large transport experiences cabin pressurization problems. Emergency declared. Re...

Attributes
ACN	353657
Time
Date	199611
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mem
State Reference	TN
Altitude	msl bound lower : 12000 msl bound upper : 12000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zme
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude other other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 14000 flight time type : 11000
ASRS Report	353657
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : less severe other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Took off from mem for aus after 3 hour delay for a duct leak problem from previous day. 78 passenger, 2 flight attendants, 2 cockpit crew and 1 in the jump seat. On climb out noticed pitch control of autoplt inoperative. Passing 10000 ft the cabin pressure began to climb rapidly. We had to stop at 12000 ft to stop it as manual control did not fix it. Went through all checklists and tried to climb again but it still didn't work. We then took vectors back to mem and had to declare an emergency due to overweight condition for landing. Configured the aircraft for landing about 40 mi out to burn down weight. The copilot flew while the captain talked on the radios to dispatch and briefed the flight attendants. We had the jump seater control the cabin with the manual control. It worked going down, not up. Flight attendants briefed passenger and after all checklists were complete, captain flew approach and landing. Equipment was standing by. Landing only 1200 pounds over maximum landing weight. 130 KTS or less than 200 FPM descent. Uneventful landing and rollout. All passenger cheered.

Original NASA ASRS Text

Title: ACR MLG EXPERIENCES CABIN PRESSURIZATION PROBS. EMER DECLARED. RETURN LAND.

Narrative: TOOK OFF FROM MEM FOR AUS AFTER 3 HR DELAY FOR A DUCT LEAK PROB FROM PREVIOUS DAY. 78 PAX, 2 FLT ATTENDANTS, 2 COCKPIT CREW AND 1 IN THE JUMP SEAT. ON CLBOUT NOTICED PITCH CTL OF AUTOPLT INOP. PASSING 10000 FT THE CABIN PRESSURE BEGAN TO CLB RAPIDLY. WE HAD TO STOP AT 12000 FT TO STOP IT AS MANUAL CTL DID NOT FIX IT. WENT THROUGH ALL CHKLISTS AND TRIED TO CLB AGAIN BUT IT STILL DIDN'T WORK. WE THEN TOOK VECTORS BACK TO MEM AND HAD TO DECLARE AN EMER DUE TO OVERWT CONDITION FOR LNDG. CONFIGURED THE ACFT FOR LNDG ABOUT 40 MI OUT TO BURN DOWN WT. THE COPLT FLEW WHILE THE CAPT TALKED ON THE RADIOS TO DISPATCH AND BRIEFED THE FLT ATTENDANTS. WE HAD THE JUMP SEATER CTL THE CABIN WITH THE MANUAL CTL. IT WORKED GOING DOWN, NOT UP. FLT ATTENDANTS BRIEFED PAX AND AFTER ALL CHKLISTS WERE COMPLETE, CAPT FLEW APCH AND LNDG. EQUIP WAS STANDING BY. LNDG ONLY 1200 LBS OVER MAX LNDG WT. 130 KTS OR LESS THAN 200 FPM DSCNT. UNEVENTFUL LNDG AND ROLLOUT. ALL PAX CHEERED.

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.

Air carrier medium large transport experiences cabin pressurization problems. Emergency declared. Return land.