A B737-300 cabin altitude warning horn sounded at cruise FL240 with one engine bleed MEL'ed and the ...

Narrative:

We originated the aircraft with the number one engine bleed inoperable (wired closed) MEL 36-5. Takeoff was on time and we climbed to fl 240. At level off; pressurization indicated a cabin altitude of 3000'. Some time later the cabin altitude warning horn sounded. The immediate action items for cabin altitude warning/abnormal pressurization checklist were performed. The cabin altitude indicated just over 10;000' and ATC was advised that we needed an immediate descent due to pressurization problems. I performed a rapid descent to 10;000'. After completing the checklist; the APU was started and the left pack was turned on. We climbed back up to 16;000'. With the pressurization stabilized and controllable; we proceeded to our destination. A note added to the MEL stating; 'to consider placing the remaining pack in high' would be helpful.

Original NASA ASRS Text

Title: A B737-300 CABIN ALTITUDE WARNING horn sounded at cruise FL240 with one engine bleed MEL'ed and the associated pack OFF. After a descent to 10;000' the APU was started; the left pack turned ON and the flight climbed to 16;000' while continuing to its planned destination.

Narrative: We originated the aircraft with the number one Engine Bleed Inoperable (Wired Closed) MEL 36-5. Takeoff was on time and we climbed to FL 240. At level off; pressurization indicated a cabin altitude of 3000'. Some time later the Cabin Altitude Warning horn sounded. The immediate action items for Cabin Altitude Warning/Abnormal Pressurization Checklist were performed. The cabin altitude indicated just over 10;000' and ATC was advised that we needed an immediate descent due to pressurization problems. I performed a rapid descent to 10;000'. After completing the checklist; the APU was started and the left pack was turned on. We climbed back up to 16;000'. With the pressurization stabilized and controllable; we proceeded to our destination. A note added to the MEL stating; 'To consider placing the remaining pack in high' would be helpful.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	929603
Time
Date	201101
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Pneumatic Valve/Bleed Valve
Person 1
Function	First Officer Pilot Flying
Experience	Flight Crew Last 90 Days 229
Person 2
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical

A B737-300 cabin altitude warning horn sounded at cruise FL240 with one engine bleed MEL'ed and the associated pack off. After a descent to 10;000' the APU was started; the left pack turned on and the flight climbed to 16;000' while continuing to its planned destination.