Air carrier widebody transport pressurization system failure.

Attributes
ACN	144565
Time
Date	199005
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : yay
State Reference	NF
Altitude	msl bound lower : 31000 msl bound upper : 37000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : czqx
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other other
Route In Use	enroute : atlantic enroute : other oceanic
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 50 flight time total : 12000 flight time type : 1000
ASRS Report	144565
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : declared emergency flight crew : regained aircraft control
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

#2 engine bleed faulted with subsequent loss of #2 pack. Xbleed selected to regain use of #2 pack when #1 pack faulted. Attempts to reset either #1 or #2 pack were unsuccessful and west/O pressurization, an emergency descent was declared with gander center. Passing FL340, the #1 pack reset and with pressurization restored, gander honored request to maintain first FL330, then FL310. 20 min later, #2 pack and bleed reset with normal operation restored. Cabin altitude reached approximately 9000' during incident. Gander center very helpful.

Original NASA ASRS Text

Title: ACR WDB PRESSURIZATION SYSTEM FAILURE.

Narrative: #2 ENG BLEED FAULTED WITH SUBSEQUENT LOSS OF #2 PACK. XBLEED SELECTED TO REGAIN USE OF #2 PACK WHEN #1 PACK FAULTED. ATTEMPTS TO RESET EITHER #1 OR #2 PACK WERE UNSUCCESSFUL AND W/O PRESSURIZATION, AN EMER DSNT WAS DECLARED WITH GANDER CTR. PASSING FL340, THE #1 PACK RESET AND WITH PRESSURIZATION RESTORED, GANDER HONORED REQUEST TO MAINTAIN FIRST FL330, THEN FL310. 20 MIN LATER, #2 PACK AND BLEED RESET WITH NORMAL OPERATION RESTORED. CABIN ALT REACHED APPROX 9000' DURING INCIDENT. GANDER CTR VERY HELPFUL.

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.