Aircraft equipment problem malfunction creates need for emergency declared descent and diversion to ...

Attributes
ACN	238357
Time
Date	199304
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : clt
State Reference	NC
Altitude	msl bound lower : 41000 msl bound upper : 41000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ztl
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other other other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : flight engineer pilot : atp pilot : commercial
Experience	flight time last 90 days : 127 flight time total : 15100 flight time type : 127
ASRS Report	238357
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : flight engineer pilot : instrument pilot : atp pilot : cfi
Experience	flight time last 90 days : 85 flight time total : 11500 flight time type : 2100
ASRS Report	238690
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : exited adverse environment flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

While at cruise at FL410 a pneumatic bleed valve faulted and closed. I requested a lower altitude and a pneumatic abnormal procedure was initiated. Seconds later, the second pneumatic bleed valve faulted and the cabin altitude rose rapidly. I declared an emergency condition to controling center. An emergency descent and emergency descent checklist was accomplished. We diverted to charlotte where a normal approach and landing was completed. I feel the flight crew was prompted and followed an abnormal procedure by the aircraft electronic centralized aircraft monitor which was not adequate for the situation. Supplemental information from acn 238690: oxygen masks were donned and emergency descent begun. Passenger masks deployed normally at 14000 ft cabin altitude. Maximum cabin altitude was 15000 ft. Aircraft descended at vmo to 10000 ft MSL. All aircraft initial action and abnormal checklists were adequate for this emergency. At this time I do not know the reasons for the system malfunction.

Original NASA ASRS Text

Title: ACFT EQUIP PROB MALFUNCTION CREATES NEED FOR EMER DECLARED DSCNT AND DIVERSION TO ALTERNATE ARPT.

Narrative: WHILE AT CRUISE AT FL410 A PNEUMATIC BLEED VALVE FAULTED AND CLOSED. I REQUESTED A LOWER ALT AND A PNEUMATIC ABNORMAL PROC WAS INITIATED. SECONDS LATER, THE SECOND PNEUMATIC BLEED VALVE FAULTED AND THE CABIN ALT ROSE RAPIDLY. I DECLARED AN EMER CONDITION TO CTLING CTR. AN EMER DSCNT AND EMER DSCNT CHKLIST WAS ACCOMPLISHED. WE DIVERTED TO CHARLOTTE WHERE A NORMAL APCH AND LNDG WAS COMPLETED. I FEEL THE FLC WAS PROMPTED AND FOLLOWED AN ABNORMAL PROC BY THE ACFT ELECTRONIC CENTRALIZED ACFT MONITOR WHICH WAS NOT ADEQUATE FOR THE SIT. SUPPLEMENTAL INFO FROM ACN 238690: OXYGEN MASKS WERE DONNED AND EMER DSCNT BEGUN. PAX MASKS DEPLOYED NORMALLY AT 14000 FT CABIN ALT. MAX CABIN ALT WAS 15000 FT. ACFT DSNDED AT VMO TO 10000 FT MSL. ALL ACFT INITIAL ACTION AND ABNORMAL CHKLISTS WERE ADEQUATE FOR THIS EMER. AT THIS TIME I DO NOT KNOW THE REASONS FOR THE SYS MALFUNCTION.

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.

Aircraft equipment problem malfunction creates need for emergency declared descent and diversion to alternate airport.