Narrative:

On a day of moderate dry snow activity, the aircraft (an large transport) was decided at the gate prior to pushback. After taxi-out we faced a minimum delay of aircraft ahead of us for takeoff. When we moved to the #1 position for takeoff, the captain called for flaps 15 degrees for takeoff. An aircraft behind us then informed us on tower frequency that there appeared to be some deicing fluid that ran back onto the trailing edge flaps and refroze. The aircraft said that it was on a small area on the right flap. The captain asked me to go into the aft cabin and look at the flaps. The flaps appeared to be clean, with no evidence of ice. This was after the aircraft had taxied further. I informed the captain of not seeing anything on the flaps. The captain elected to takeoff. There were no further occurrences and everything else was normal. My opinion was that what was seen from the other aircraft was observed wrong, or that moisture or deicing fluid ran off the flap after the aircraft taxied further. The possible precipitation was not noticeable with the flaps in the up position.

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Original NASA ASRS Text

Title: FLT CREW OF ACR LGT RECEIVED A REPORT VIA PARTYLINE THAT THEY HAD ICE ON THEIR TRAILING EDGE FLAPS. AN ACFT BEHIND THEM NOTICED THE ICE AS THE FLAPS WERE EXTENDED. IN POSITION FOR TKOF, THE FO CHECKED THE FLAPS BUT COULD SEE NO ICE, SO TKOF WAS CONTINUED.

Narrative: ON A DAY OF MODERATE DRY SNOW ACTIVITY, THE ACFT (AN LGT) WAS DECIDED AT THE GATE PRIOR TO PUSHBACK. AFTER TAXI-OUT WE FACED A MINIMUM DELAY OF ACFT AHEAD OF US FOR TKOF. WHEN WE MOVED TO THE #1 POS FOR TKOF, THE CAPT CALLED FOR FLAPS 15 DEGS FOR TKOF. AN ACFT BEHIND US THEN INFORMED US ON TWR FREQ THAT THERE APPEARED TO BE SOME DEICING FLUID THAT RAN BACK ONTO THE TRAILING EDGE FLAPS AND REFROZE. THE ACFT SAID THAT IT WAS ON A SMALL AREA ON THE RIGHT FLAP. THE CAPT ASKED ME TO GO INTO THE AFT CABIN AND LOOK AT THE FLAPS. THE FLAPS APPEARED TO BE CLEAN, WITH NO EVIDENCE OF ICE. THIS WAS AFTER THE ACFT HAD TAXIED FURTHER. I INFORMED THE CAPT OF NOT SEEING ANYTHING ON THE FLAPS. THE CAPT ELECTED TO TKOF. THERE WERE NO FURTHER OCCURRENCES AND EVERYTHING ELSE WAS NORMAL. MY OPINION WAS THAT WHAT WAS SEEN FROM THE OTHER ACFT WAS OBSERVED WRONG, OR THAT MOISTURE OR DEICING FLUID RAN OFF THE FLAP AFTER THE ACFT TAXIED FURTHER. THE POSSIBLE PRECIPITATION WAS NOT NOTICEABLE WITH THE FLAPS IN THE UP POS.

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.