B737 flight crew reported a loss of cabin pressure while at cruise altitude. After conducting an eme...

Attributes
ACN	1498079
Time
Date	201711
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZZ.ARTCC
State Reference	FO
Aircraft 1
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Pressurization System
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 142
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

While at cruise altitude FL400 we had an altitude warning light illuminate with the associated warning horn. We completed the appropriate checklist donning our oxygen mask and beginning an emergency descent. ATC was notified; inflight crew was coordinated with and company was notified via ACARS. At approximately 22;000 feet we regained control of the cabin and continued a normal descent to 14;000 feet to ensure terrain clearances. We returned to [departure airport] and made a normal landing.

Original NASA ASRS Text

Title: B737 flight crew reported a loss of cabin pressure while at cruise altitude. After conducting an emergency descent; cabin pressurization was stabilized; and a return to the departure airport was successfully accomplished.

Narrative: While at cruise altitude FL400 we had an altitude warning light illuminate with the associated warning horn. We completed the appropriate checklist donning our oxygen mask and beginning an emergency descent. ATC was notified; inflight crew was coordinated with and company was notified via ACARS. At approximately 22;000 feet we regained control of the cabin and continued a normal descent to 14;000 feet to ensure terrain clearances. We returned to [departure airport] and made a normal landing.

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.