Narrative:

We landed after an ILS approach. Weather was: 005BKN 3/4SM -snbr temperature 01C. The braking action was reported good by company aircraft approximately five minutes prior to our landing. There was light mixed icing on the arrival/approach. Upon exiting the runway; retracted flaps as normal and taxied to gate. There was some light; wet snow accumulation on the taxiway and ramp surfaces. A flaps 15 retraction after landing for flap inspection upon arrival was not considered; the conditions did not appear to warrant it. The focus was on a safe runway crossing and taxi in the reduced visibility conditions. When we pushed for the next leg we ended up with an approximately 90-minute delay for deicing. We configured for a flaps 5 departure just after pushback; as normal; and then joined the line for deice. When we finally deiced (type I and iv); the engines were shut down. The deice crew was split between two trucks and said that they would remove some accumulation around our landing gear. The deice was routine other than the long delay. We departed and flew the next leg which was 4:10 block with a hold and a divert consideration due to thunderstorms. The next leg; while maneuvering around the weather on climbout; we noticed some unusual trim inputs were needed to coordinate the aircraft. The captain (now the pilot flying) flew with both the autopilot on and off to evaluate the aircraft's handling. The autopilot appeared to handle the trim requirements when on; when off; the aircraft was somewhat awkward to coordinate with the trim. We had no cockpit indication of asymmetry due to either flight controls or engine thrust. We consulted the QRH and discussed any appropriate action that might be taken; and agreed that the aircraft was safe to fly; trimmed a little bit unusually; but we might investigate further upon arrival. Upon a normal arrival and visual approach; the post-flight inspection revealed a partially extended outer panel of the left wing inboard trailing edge flap. The flaps were selected up after landing as normal; and there had never been any cockpit indication of asymmetry other than the unusual trim.

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Original NASA ASRS Text

Title: B737 flight crew discovers flap damage during post flight inspection after noting abnormal trim requirements during flight. The damage may have occurred earlier in the day after approach and landing in icing conditions; when the flaps were retracted after landing without being inspected.

Narrative: We landed after an ILS approach. Weather was: 005BKN 3/4SM -SNBR temperature 01C. The braking action was reported good by Company aircraft approximately five minutes prior to our landing. There was light mixed icing on the arrival/approach. Upon exiting the runway; retracted flaps as normal and taxied to gate. There was some light; wet snow accumulation on the taxiway and ramp surfaces. A flaps 15 retraction after landing for flap inspection upon arrival was not considered; the conditions did not appear to warrant it. The focus was on a safe runway crossing and taxi in the reduced visibility conditions. When we pushed for the next leg we ended up with an approximately 90-minute delay for deicing. We configured for a flaps 5 departure just after pushback; as normal; and then joined the line for deice. When we finally deiced (Type I and IV); the engines were shut down. The Deice Crew was split between two trucks and said that they would remove some accumulation around our landing gear. The deice was routine other than the long delay. We departed and flew the next leg which was 4:10 block with a hold and a divert consideration due to thunderstorms. The next leg; while maneuvering around the weather on climbout; we noticed some unusual trim inputs were needed to coordinate the aircraft. The Captain (now the pilot flying) flew with both the autopilot on and off to evaluate the aircraft's handling. The autopilot appeared to handle the trim requirements when on; when off; the aircraft was somewhat awkward to coordinate with the trim. We had no cockpit indication of asymmetry due to either flight controls or engine thrust. We consulted the QRH and discussed any appropriate action that might be taken; and agreed that the aircraft was safe to fly; trimmed a little bit unusually; but we might investigate further upon arrival. Upon a normal arrival and visual approach; the post-flight inspection revealed a partially extended outer panel of the left wing inboard trailing edge flap. The flaps were selected up after landing as normal; and there had never been any cockpit indication of asymmetry other than the unusual trim.

Data retrieved from NASA's ASRS site as of April 2012 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.