Upon receipt of a cabin altitude warning a B757 flight crew declared and emergency and initiated an ...

Attributes
ACN	1166150
Time
Date	201404
Local Time Of Day	1801-2400
Place
Locale Reference	ZDV.ARTCC
State Reference	CO
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Pressurization Outflow Valve
Person 1
Function	First Officer Pilot Not Flying
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

[We] received cabin altitude master warning. Cabin altitude increased to 10;000; at FL360; autopilot disengaged; [we] donned masks and accomplished QRH for cabin altitude. Contacted ATC; declared emergency and initiated descent. Descending through FL260 switched auto controller 2 to auto 1; with no effect. Descending through FL200 cabin altitude began to decrease to 8;000. Diverted to a nearby airport and landed with no further issue. Maintenance found a piece of debris lodged in the over pressure valve.

Original NASA ASRS Text

Title: Upon receipt of a cabin altitude warning a B757 flight crew declared and emergency and initiated an emergency descent. They diverted to a nearby airport where Maintenance found debris blocking the overpressure valve open.

Narrative: [We] received cabin altitude master warning. Cabin altitude increased to 10;000; at FL360; autopilot disengaged; [we] donned masks and accomplished QRH for cabin altitude. Contacted ATC; declared emergency and initiated descent. Descending through FL260 switched auto controller 2 to auto 1; with no effect. Descending through FL200 cabin altitude began to decrease to 8;000. Diverted to a nearby airport and landed with no further issue. Maintenance found a piece of debris lodged in the over pressure valve.

Data retrieved from NASA's ASRS site 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.

Upon receipt of a cabin altitude warning a B757 flight crew declared and emergency and initiated an emergency descent. They diverted to a nearby airport where maintenance found debris blocking the overpressure valve open.