B767 crew experiences outflow valve failure on climb out and returns.

Attributes
ACN	719175
Time
Date	200612
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zzz.artcc
State Reference	US
Altitude	msl single value : 28000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zzz.artcc
Operator	common carrier : air carrier
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	climbout : vacating altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 150 flight time total : 12000 flight time type : 3000
ASRS Report	719175
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer oversight : pic
Experience	flight time last 90 days : 150 flight time total : 16000 flight time type : 400
ASRS Report	719176
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

During climb out; at FL280 automatic #1 fail on EICAS; followed shortly with automatic #2 fail. Went to irregular procedure. Next step went to manual pressurization. Could not control outflow valve in manual. Declared emergency for descent and traffic clearance. Descended to 10000 ft. Cabin altitude only climbed to 8500 ft. Return to ZZZ. No passenger complaints; but 4 flight attendants had blocked ears.

Original NASA ASRS Text

Title: B767 CREW EXPERIENCES OUTFLOW VALVE FAILURE ON CLBOUT AND RETURNS.

Narrative: DURING CLBOUT; AT FL280 AUTO #1 FAIL ON EICAS; FOLLOWED SHORTLY WITH AUTO #2 FAIL. WENT TO IRREGULAR PROC. NEXT STEP WENT TO MANUAL PRESSURIZATION. COULD NOT CTL OUTFLOW VALVE IN MANUAL. DECLARED EMER FOR DSCNT AND TFC CLRNC. DSNDED TO 10000 FT. CABIN ALT ONLY CLBED TO 8500 FT. RETURN TO ZZZ. NO PAX COMPLAINTS; BUT 4 FLT ATTENDANTS HAD BLOCKED EARS.

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