A DC9 crew, during cruise at FL310, experienced a loss of cabin pressure, spawning an emergency desc...

Attributes
ACN	552765
Time
Date	200207
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : fsm.vortac
State Reference	AR
Altitude	msl single value : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme.artcc
Operator	common carrier : air carrier
Make Model Name	DC-9 30
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 12000 flight time type : 7000
ASRS Report	552765
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : callback alt indicator other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance controller : provided flight assist flight crew : declared emergency flight crew : diverted to another airport flight crew : landed as precaution none taken : detected after the fact other
Consequence	faa : reviewed incident with flight crew other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

At FL310, the first officer and I felt a pressure change. I immediately checked cabin altitude and noticed a rapid cabin climb. The first officer and I donned our oxygen masks and performed the memory checklist items. I then completed the checklist with the first officer who had already begun the descent to FL240 with an ATC clearance. I contacted the #1 flight attendant and informed him the masks would probably drop, which they did. We were able to hold a 9500 ft cabin at FL200. I then discussed our position with the first officer and we both agreed that dkw was the nearest suitable airport. I made a PA to the passenger explaining the depressurization after discussion with dispatch and maintenance control on the cockpit phone.

Original NASA ASRS Text

Title: A DC9 CREW, DURING CRUISE AT FL310, EXPERIENCED A LOSS OF CABIN PRESSURE, SPAWNING AN EMER DSCNT TO FL200.

Narrative: AT FL310, THE FO AND I FELT A PRESSURE CHANGE. I IMMEDIATELY CHKED CABIN ALT AND NOTICED A RAPID CABIN CLB. THE FO AND I DONNED OUR OXYGEN MASKS AND PERFORMED THE MEMORY CHKLIST ITEMS. I THEN COMPLETED THE CHKLIST WITH THE FO WHO HAD ALREADY BEGUN THE DSCNT TO FL240 WITH AN ATC CLRNC. I CONTACTED THE #1 FLT ATTENDANT AND INFORMED HIM THE MASKS WOULD PROBABLY DROP, WHICH THEY DID. WE WERE ABLE TO HOLD A 9500 FT CABIN AT FL200. I THEN DISCUSSED OUR POS WITH THE FO AND WE BOTH AGREED THAT DKW WAS THE NEAREST SUITABLE ARPT. I MADE A PA TO THE PAX EXPLAINING THE DEPRESSURIZATION AFTER DISCUSSION WITH DISPATCH AND MAINT CTL ON THE COCKPIT PHONE.

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.

A DC9 crew, during cruise at FL310, experienced a loss of cabin pressure, spawning an emergency descent to FL200.