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|
Attributes | |
ACN | 708135 |
Time | |
Date | 200608 |
Local Time Of Day | 0001 To 0600 |
Place | |
Locale Reference | airport : zzz.airport |
State Reference | US |
Altitude | agl single value : 0 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | B737 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | ground : preflight ground : parked |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Experience | flight time last 90 days : 200 flight time type : 1000 |
ASRS Report | 708135 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Experience | flight time last 90 days : 150 flight time type : 150 |
ASRS Report | 708133 |
Events | |
Anomaly | aircraft equipment problem : critical maintenance problem : non compliance with mel non adherence : published procedure non adherence : far |
Independent Detector | other flight crewa other flight crewb |
Resolutory Action | none taken : detected after the fact |
Consequence | other |
Factors | |
Maintenance | performance deficiency : non compliance with legal requirements performance deficiency : logbook entry |
Supplementary | |
Problem Areas | Aircraft Chart Or Publication Flight Crew Human Performance Maintenance Human Performance |
Primary Problem | Maintenance Human Performance |
Narrative:
MEL34-45C on flight paperwork was reviewed in the MEL and crosschecked with maintenance log. The MEL number on the dispatch release correlated to the MEL book. Due to location of MEL placard directly below #1 IRS switch; I determined that the #1 IRS should not be pwred. All system seemed to work properly until after takeoff when my primary flight director did not produce vertical guidance and neither autoplt would engage. The QRH reference 11.5 was referred to; but it didn't fit the situation (there was no IRS fault light illuminated). ZZZ maintenance was contacted and they referenced QRH 11.5 and ZZZ1 maintenance control. Maintenance and dispatch were briefed of situation. Once the aircraft heading was manually entered into the FMC and the IRS mode switch placed to normal; the autoplt could be engaged and the flight continued to destination uneventfully. Relocate the MEL placard for this particular MEL (34-45C) to location that would not lead a pilot to leave the IRS off. Additionally; wording could be placed in the MEL to indicate both IRS mode select switches need to be in the navigation position for proper flight director and autoplt use.
Original NASA ASRS Text
Title: A B737-900 DEFERRED ITEM PLACARD WAS IMPROPERLY LOCATED; LEADING THE FLT CREW TO BELIEVE THE #1 IRS SHOULD NOT BE OPERATED.
Narrative: MEL34-45C ON FLT PAPERWORK WAS REVIEWED IN THE MEL AND XCHKED WITH MAINT LOG. THE MEL NUMBER ON THE DISPATCH RELEASE CORRELATED TO THE MEL BOOK. DUE TO LOCATION OF MEL PLACARD DIRECTLY BELOW #1 IRS SWITCH; I DETERMINED THAT THE #1 IRS SHOULD NOT BE PWRED. ALL SYS SEEMED TO WORK PROPERLY UNTIL AFTER TKOF WHEN MY PRIMARY FLT DIRECTOR DID NOT PRODUCE VERT GUIDANCE AND NEITHER AUTOPLT WOULD ENGAGE. THE QRH REF 11.5 WAS REFERRED TO; BUT IT DIDN'T FIT THE SITUATION (THERE WAS NO IRS FAULT LIGHT ILLUMINATED). ZZZ MAINT WAS CONTACTED AND THEY REFED QRH 11.5 AND ZZZ1 MAINT CTL. MAINT AND DISPATCH WERE BRIEFED OF SITUATION. ONCE THE ACFT HDG WAS MANUALLY ENTERED INTO THE FMC AND THE IRS MODE SWITCH PLACED TO NORMAL; THE AUTOPLT COULD BE ENGAGED AND THE FLT CONTINUED TO DEST UNEVENTFULLY. RELOCATE THE MEL PLACARD FOR THIS PARTICULAR MEL (34-45C) TO LOCATION THAT WOULD NOT LEAD A PLT TO LEAVE THE IRS OFF. ADDITIONALLY; WORDING COULD BE PLACED IN THE MEL TO INDICATE BOTH IRS MODE SELECT SWITCHES NEED TO BE IN THE NAV POS FOR PROPER FLT DIRECTOR AND AUTOPLT USE.
Data retrieved from NASA's ASRS site as of January 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.