An A32O captain reported that there is a significant problem with the crew oxygen system which does ...

Attributes
ACN	632124
Time
Date	200409
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : dta.vortac
State Reference	UT
Altitude	msl single value : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zlc.artcc tower : cdw.tower
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : flight engineer pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 125 flight time total : 18000 flight time type : 3000
ASRS Report	632124
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : ecam other flight crewa
Resolutory Action	controller : issued new clearance flight crew : diverted to another airport flight crew : declared emergency
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

At about 2 hours 20 mins into the flight, the captain and first officer needed to leave the flight deck for physiological reasons. The captain was to go first. The lead flight attendant was called into the flight deck as per SOP and the captain prepared to leave. The first officer pulled his oxygen mask and noticed no oxygen pressure. The captain checked his mask then and had the same results. Checking the door ECAM page, the oxygen system showed 'oxy-xx, regulator low pressure.' the captain immediately asked the lead to return to the cabin and procure 2 portable oxygen bottles. The captain checked the communication oxygen section. Its instructions left little doubt as to the next course of action. The captain declared an emergency with ZLC and requested diversion and descent to slc. The captain called dispatch and maintenance to get concurrence in the plan of action. They agreed and dispatch authorized diversion. An uneventful approach and landing were conducted into slc. The emergency was canceled on the ground. The captain entered the discrepancy into the ship's logbook. Both the captain and first officer are highly experienced in the airbus. They are familiar with the previous A320 bulletins that highlighted preflight faults that could lead to this problem. They conducted their preflts normally for the flight. The first officer noticed that during his preflight, his oxygen white tab was out as he started his preflight. He tested his mask normally and reset the mask to the correct stowed position with the tab out of sight. Oxygen pressure during preflight was 1050 psi. The logbook for ship had a previous write-up that stated the captain's oxygen mask was leaking. It was replaced. The captain's preflight was normal. Recommendation: the airbus 319/320 has no warning for the gradual loss of crew oxygen. The only readout is on the door ECAM page. The only alert occurs when it is too late. It should be displayed on the cruise ECAM, so that it can be monitored.

Original NASA ASRS Text

Title: AN A32O CAPT RPTED THAT THERE IS A SIGNIFICANT PROB WITH THE CREW OXYGEN SYS WHICH DOES NOT DIRECTLY INDICATE WHEN THERE IS A SLOW LEAK. SUCH A PROB CAUSED HIM TO DECLARE AN EMER AND DIVERT TO SLC.

Narrative: AT ABOUT 2 HRS 20 MINS INTO THE FLT, THE CAPT AND FO NEEDED TO LEAVE THE FLT DECK FOR PHYSIOLOGICAL REASONS. THE CAPT WAS TO GO FIRST. THE LEAD FLT ATTENDANT WAS CALLED INTO THE FLT DECK AS PER SOP AND THE CAPT PREPARED TO LEAVE. THE FO PULLED HIS OXYGEN MASK AND NOTICED NO OXYGEN PRESSURE. THE CAPT CHKED HIS MASK THEN AND HAD THE SAME RESULTS. CHKING THE DOOR ECAM PAGE, THE OXYGEN SYS SHOWED 'OXY-XX, REGULATOR LOW PRESSURE.' THE CAPT IMMEDIATELY ASKED THE LEAD TO RETURN TO THE CABIN AND PROCURE 2 PORTABLE OXYGEN BOTTLES. THE CAPT CHKED THE COM OXYGEN SECTION. ITS INSTRUCTIONS LEFT LITTLE DOUBT AS TO THE NEXT COURSE OF ACTION. THE CAPT DECLARED AN EMER WITH ZLC AND REQUESTED DIVERSION AND DSCNT TO SLC. THE CAPT CALLED DISPATCH AND MAINT TO GET CONCURRENCE IN THE PLAN OF ACTION. THEY AGREED AND DISPATCH AUTHORIZED DIVERSION. AN UNEVENTFUL APCH AND LNDG WERE CONDUCTED INTO SLC. THE EMER WAS CANCELED ON THE GND. THE CAPT ENTERED THE DISCREPANCY INTO THE SHIP'S LOGBOOK. BOTH THE CAPT AND FO ARE HIGHLY EXPERIENCED IN THE AIRBUS. THEY ARE FAMILIAR WITH THE PREVIOUS A320 BULLETINS THAT HIGHLIGHTED PREFLT FAULTS THAT COULD LEAD TO THIS PROB. THEY CONDUCTED THEIR PREFLTS NORMALLY FOR THE FLT. THE FO NOTICED THAT DURING HIS PREFLT, HIS OXYGEN WHITE TAB WAS OUT AS HE STARTED HIS PREFLT. HE TESTED HIS MASK NORMALLY AND RESET THE MASK TO THE CORRECT STOWED POS WITH THE TAB OUT OF SIGHT. OXYGEN PRESSURE DURING PREFLT WAS 1050 PSI. THE LOGBOOK FOR SHIP HAD A PREVIOUS WRITE-UP THAT STATED THE CAPT'S OXYGEN MASK WAS LEAKING. IT WAS REPLACED. THE CAPT'S PREFLT WAS NORMAL. RECOMMENDATION: THE AIRBUS 319/320 HAS NO WARNING FOR THE GRADUAL LOSS OF CREW OXYGEN. THE ONLY READOUT IS ON THE DOOR ECAM PAGE. THE ONLY ALERT OCCURS WHEN IT IS TOO LATE. IT SHOULD BE DISPLAYED ON THE CRUISE ECAM, SO THAT IT CAN BE MONITORED.

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.

An A32O captain reported that there is a significant problem with the crew oxygen system which does not directly indicate when there is a slow leak. Such a problem caused him to declare an emergency and divert to slc.