Narrative:

This was our first flight with this large transport and it had been written up twice in the preceeding 24 hours for a flap indicator problem which was cleared by replacing the indicator. Because of vectors for other traffic landing, I did not configure the aircraft beyond 5 degree flaps until approximately 1500' AGL. During flap extension, the inboard flaps indication stopped a little past 5 degree, and as there were no unusual control problems, I continued the approach. All of us on the crew assumed that the indicator was malfunctioning once more, and I just flew a faster than normal approach 'just in case'. I left the flaps extended after an uneventful landing on a hunch that it might help the maintenance folks. What we found was that the indicator was correct, the flaps had stopped at 5 degree (the inboard flaps, outboards at their normal 30 degree position) because of a jackscrew that needed to be lubricated. The outcome on this one was pleasant, I hope I learn the lesson not to 'assume' anything before it becomes costly. Supplemental information from acn 152685. The inboard flap indicator stopped at 5 degree. The outboard indicator continued normally to 30 degree as selected. During the post-flight inspection I discovered the inboard flaps were at 5 degree and the outboards at 30 degree. The previous write-ups had lulled us into a false sense of security, that the indicator was the problem. I believe other crews may have had the same problem west/O knowing it and west/O maintenance discovering or fixing the real problem. Leaving the confign alone after landing was a good idea, but we should have run the 'jammed flap' checklist despite the fact we believed we just had another indicator malfunction. Lesson learned, don't assume 'a bad gauge' even if there is a maintenance history.

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Original NASA ASRS Text

Title: FLT CREW OF ACR MLG ON APCH INTO ALB MISTAKENLY BELIEVES THAT THE FLAP POSITION INDICATOR IS MALFUNCTIONING DUE TO PREVIOUS PROBLEMS WITH IT. ACFT WAS LANDED WITH THE INBOARD FLAPS AT FIVE DEGREES INSTEAD OF 30 DEGREES BECAUSE OF PROBLEMATIC JACKSCREWS. OUTBOARD FLAPS WERE AT 30 DEGREES BUT INDICATOR SHOWED FIVE.

Narrative: THIS WAS OUR FIRST FLT WITH THIS LGT AND IT HAD BEEN WRITTEN UP TWICE IN THE PRECEEDING 24 HRS FOR A FLAP INDICATOR PROB WHICH WAS CLRED BY REPLACING THE INDICATOR. BECAUSE OF VECTORS FOR OTHER TFC LNDG, I DID NOT CONFIGURE THE ACFT BEYOND 5 DEG FLAPS UNTIL APPROX 1500' AGL. DURING FLAP EXTENSION, THE INBOARD FLAPS INDICATION STOPPED A LITTLE PAST 5 DEG, AND AS THERE WERE NO UNUSUAL CTL PROBS, I CONTINUED THE APCH. ALL OF US ON THE CREW ASSUMED THAT THE INDICATOR WAS MALFUNCTIONING ONCE MORE, AND I JUST FLEW A FASTER THAN NORMAL APCH 'JUST IN CASE'. I LEFT THE FLAPS EXTENDED AFTER AN UNEVENTFUL LNDG ON A HUNCH THAT IT MIGHT HELP THE MAINT FOLKS. WHAT WE FOUND WAS THAT THE INDICATOR WAS CORRECT, THE FLAPS HAD STOPPED AT 5 DEG (THE INBOARD FLAPS, OUTBOARDS AT THEIR NORMAL 30 DEG POS) BECAUSE OF A JACKSCREW THAT NEEDED TO BE LUBRICATED. THE OUTCOME ON THIS ONE WAS PLEASANT, I HOPE I LEARN THE LESSON NOT TO 'ASSUME' ANYTHING BEFORE IT BECOMES COSTLY. SUPPLEMENTAL INFO FROM ACN 152685. THE INBOARD FLAP INDICATOR STOPPED AT 5 DEG. THE OUTBOARD INDICATOR CONTINUED NORMALLY TO 30 DEG AS SELECTED. DURING THE POST-FLT INSPECTION I DISCOVERED THE INBOARD FLAPS WERE AT 5 DEG AND THE OUTBOARDS AT 30 DEG. THE PREVIOUS WRITE-UPS HAD LULLED US INTO A FALSE SENSE OF SECURITY, THAT THE INDICATOR WAS THE PROB. I BELIEVE OTHER CREWS MAY HAVE HAD THE SAME PROB W/O KNOWING IT AND W/O MAINT DISCOVERING OR FIXING THE REAL PROB. LEAVING THE CONFIGN ALONE AFTER LNDG WAS A GOOD IDEA, BUT WE SHOULD HAVE RUN THE 'JAMMED FLAP' CHKLIST DESPITE THE FACT WE BELIEVED WE JUST HAD ANOTHER INDICATOR MALFUNCTION. LESSON LEARNED, DON'T ASSUME 'A BAD GAUGE' EVEN IF THERE IS A MAINT HISTORY.

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.