|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1801 To 2400|
|Locale Reference||airport : mia.airport|
|Altitude||agl single value : 0|
|Controlling Facilities||tower : cyul.tower|
|Operator||common carrier : air carrier|
|Make Model Name||B777-200|
|Operating Under FAR Part||Part 121|
|Flight Phase||ground : preflight|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Anomaly||aircraft equipment problem : less severe|
|Independent Detector||aircraft equipment other aircraft equipment : eicas|
|Resolutory Action||none taken : anomaly accepted|
After loading of a container of late bags into aft cargo; an EICAS shaded box stabilizer green band alert illuminated. Since this is not a totally unknown experience to the crew we elected to proceed normally and await the load closeout. After entering the load closeout numbers; the stabilizer green band alert remained; indicating the nose gear pressure switch disagrees with the computed stabilizer green band. As a crew; we interpreted the non-normal checklist as a call to determine which was correct -- the nose gear sensor; or the computed data. We called operations and received verification that the closeout numbers were correct and did account for the additional bags loaded. We then re-entered and rechked that the numbers were loaded correctly. Seeing an extended green band; but agreeing that the computed stabilizer value was within the body of the main stabilizer green band; we determined that the nose gear pressure switch; or the pressure sensing system was probably sitting right on a margin of error; and that the information we received and verified from load was correct and within the depicted limits. We elected to proceed with an uneventful and normal takeoff sequence. First officer's were exemplary in their research; questions; input; and support. I file this report because it is possible I misinterped the intent of the stabilizer green band checklist as a check; verify; and proceed process instead of a check; verify; do not proceed process.
Original NASA ASRS Text
Title: B777 EICAS MSG; 'STAB GREEN BAND' DISPLAYED INDICATING STABILIZER MAY NOT BE CORRECTLY SET FOR TKOF. COMPANY WAS QUERIED AS TO LOADING OF ACFT AND FLT CREW CONCLUDED THAT EICAS MSG WAS A NUISANCE WARNING; TKOF WAS CONDUCTED AND FLT CONTINUED NORMALLY.
Narrative: AFTER LOADING OF A CONTAINER OF LATE BAGS INTO AFT CARGO; AN EICAS SHADED BOX STABILIZER GREEN BAND ALERT ILLUMINATED. SINCE THIS IS NOT A TOTALLY UNKNOWN EXPERIENCE TO THE CREW WE ELECTED TO PROCEED NORMALLY AND AWAIT THE LOAD CLOSEOUT. AFTER ENTERING THE LOAD CLOSEOUT NUMBERS; THE STABILIZER GREEN BAND ALERT REMAINED; INDICATING THE NOSE GEAR PRESSURE SWITCH DISAGREES WITH THE COMPUTED STABILIZER GREEN BAND. AS A CREW; WE INTERPED THE NON-NORMAL CHKLIST AS A CALL TO DETERMINE WHICH WAS CORRECT -- THE NOSE GEAR SENSOR; OR THE COMPUTED DATA. WE CALLED OPS AND RECEIVED VERIFICATION THAT THE CLOSEOUT NUMBERS WERE CORRECT AND DID ACCOUNT FOR THE ADDITIONAL BAGS LOADED. WE THEN RE-ENTERED AND RECHKED THAT THE NUMBERS WERE LOADED CORRECTLY. SEEING AN EXTENDED GREEN BAND; BUT AGREEING THAT THE COMPUTED STABILIZER VALUE WAS WITHIN THE BODY OF THE MAIN STABILIZER GREEN BAND; WE DETERMINED THAT THE NOSE GEAR PRESSURE SWITCH; OR THE PRESSURE SENSING SYS WAS PROBABLY SITTING RIGHT ON A MARGIN OF ERROR; AND THAT THE INFO WE RECEIVED AND VERIFIED FROM LOAD WAS CORRECT AND WITHIN THE DEPICTED LIMITS. WE ELECTED TO PROCEED WITH AN UNEVENTFUL AND NORMAL TKOF SEQUENCE. FO'S WERE EXEMPLARY IN THEIR RESEARCH; QUESTIONS; INPUT; AND SUPPORT. I FILE THIS RPT BECAUSE IT IS POSSIBLE I MISINTERPED THE INTENT OF THE STABILIZER GREEN BAND CHKLIST AS A CHK; VERIFY; AND PROCEED PROCESS INSTEAD OF A CHK; VERIFY; DO NOT PROCEED PROCESS.
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.