Narrative:

We were taxiing for takeoff and we had set the flaps to 15 degrees. We had not run our checklist yet, as it was going to be a long taxi, so the #3 engine was still shut down. After some time we started #3. The tower then notified us that a plane behind us reported some of our flaps were not extended. I checked the gauge and the inboard flaps were still retracted. We cycled the flaps and bumped the inboard flaps off the detent electrically (not an approved procedure). The flaps then worked normally and we cycled them several times to verify. Then we ran our checklist and departed. No further clap problems were encountered. In retrospect this was not a prudent thing to do. We should have returned to the gate and had maintenance verify why they hadn't worked. I did it because I had seen others do the same thing before and solved the problem, and I felt it wa safe to go. It was unfortunate that due to the long taxi the flaps were in this position for some time as we wouldn't have caught it until our checklist was read.

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Original NASA ASRS Text

Title: ACR LGT ACFT EQUIPMENT MALFUNCTION. INBOARD FLAPS DID NOT EXTEND WITH OUTBOARD FLAPS AND THE PROBLEM WAS NOTICED BY AN ACFT TAXIING IN-TRAIL AND RELAYED TO THE FLT CREW THROUGH THE TWR.

Narrative: WE WERE TAXIING FOR TKOF AND WE HAD SET THE FLAPS TO 15 DEGS. WE HAD NOT RUN OUR CHKLIST YET, AS IT WAS GOING TO BE A LONG TAXI, SO THE #3 ENG WAS STILL SHUT DOWN. AFTER SOME TIME WE STARTED #3. THE TWR THEN NOTIFIED US THAT A PLANE BEHIND US RPTED SOME OF OUR FLAPS WERE NOT EXTENDED. I CHKED THE GAUGE AND THE INBOARD FLAPS WERE STILL RETRACTED. WE CYCLED THE FLAPS AND BUMPED THE INBOARD FLAPS OFF THE DETENT ELECTRICALLY (NOT AN APPROVED PROC). THE FLAPS THEN WORKED NORMALLY AND WE CYCLED THEM SEVERAL TIMES TO VERIFY. THEN WE RAN OUR CHKLIST AND DEPARTED. NO FURTHER CLAP PROBS WERE ENCOUNTERED. IN RETROSPECT THIS WAS NOT A PRUDENT THING TO DO. WE SHOULD HAVE RETURNED TO THE GATE AND HAD MAINT VERIFY WHY THEY HADN'T WORKED. I DID IT BECAUSE I HAD SEEN OTHERS DO THE SAME THING BEFORE AND SOLVED THE PROB, AND I FELT IT WA SAFE TO GO. IT WAS UNFORTUNATE THAT DUE TO THE LONG TAXI THE FLAPS WERE IN THIS POS FOR SOME TIME AS WE WOULDN'T HAVE CAUGHT IT UNTIL OUR CHKLIST WAS READ.

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.