|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1801 To 2400|
|Locale Reference||airport : zzz.airport|
|Altitude||msl single value : 34000|
|Controlling Facilities||artcc : zzz.artcc|
|Operator||common carrier : air carrier|
|Make Model Name||B737-400|
|Operating Under FAR Part||Part 121|
|Flight Phase||cruise : level|
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Experience||flight time last 90 days : 250|
flight time type : 800
|Anomaly||aircraft equipment problem : critical|
|Independent Detector||aircraft equipment other aircraft equipment : master caution light|
other flight crewa
|Resolutory Action||flight crew : diverted to another airport|
Flight Crew Human Performance
On the last leg of the day on a B737-400; cruising at FL340; we had a master caution light and IRS annunciator. The IRS showed both left and right dc fail lights on. We ran the QRH checklist for IRS dc fail (both lights on) which led us to discover our battery was depleted (approximately 8 volts) and the battery charger didn't seem to work (battery charger circuit breaker was 'in'). The checklist mentioned several inoperative system associated with loss of battery; mainly loss of fire detection capability. The checklist also mentioned to land as soon as practicable. With no battery and no fire detection; we diverted into ZZZ. Maintenance control; and dispatch concurred with the divert decision; and we debriefed with ZZZ maintenance and our flight attendants. Can't think of anything we would have done differently.
Original NASA ASRS Text
Title: B737-400 DIVERTS WHEN DUAL IRS DC FAIL LIGHTS ILLUMINATE DUE TO DEAD BATTERY.
Narrative: ON THE LAST LEG OF THE DAY ON A B737-400; CRUISING AT FL340; WE HAD A MASTER CAUTION LIGHT AND IRS ANNUNCIATOR. THE IRS SHOWED BOTH L AND R DC FAIL LIGHTS ON. WE RAN THE QRH CHKLIST FOR IRS DC FAIL (BOTH LIGHTS ON) WHICH LED US TO DISCOVER OUR BATTERY WAS DEPLETED (APPROX 8 VOLTS) AND THE BATTERY CHARGER DIDN'T SEEM TO WORK (BATTERY CHARGER CIRCUIT BREAKER WAS 'IN'). THE CHKLIST MENTIONED SEVERAL INOP SYS ASSOCIATED WITH LOSS OF BATTERY; MAINLY LOSS OF FIRE DETECTION CAPABILITY. THE CHKLIST ALSO MENTIONED TO LAND AS SOON AS PRACTICABLE. WITH NO BATTERY AND NO FIRE DETECTION; WE DIVERTED INTO ZZZ. MAINT CTL; AND DISPATCH CONCURRED WITH THE DIVERT DECISION; AND WE DEBRIEFED WITH ZZZ MAINT AND OUR FLT ATTENDANTS. CAN'T THINK OF ANYTHING WE WOULD HAVE DONE DIFFERENTLY.
Data retrieved from NASA's ASRS site as of May 2009 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.