Narrative:

After landing on and safely vacating the runway we were called on inter-phone by the door 2L flight attendant. She indicated that she thought 'a piece of the wing had flown off' during the approach. From the flight deck perspective the approach and landing had been uneventful. The aircraft had normal flight handling characteristics and no observed performance degradation. Throughout the descent and approach all flap placard speeds had been conservatively observed with extensions occurring approximately 10 knots below FM limits. We nevertheless elected to err on the side of caution and contacted maintenance while taxiing to the arrival gate. We informed local maintenance of our specific concerns. Maintenance was ready and waiting at the arrival apron. Subsequently; maintenance personnel met us in the cockpit as we completed our shutdown checklist items. As it turns out; an approximate 12 X 20 inch jagged piece of the upper left inboard slat had ripped of and was indeed missing. In reconstructing the events; the first officer and I had no recollection of a bird strike. In fact; there was no blood; feathers or other evidence to suggest that such an impact had occurred. The only logical conclusion seems to be that the leading edge somehow suffered an integral honeycomb structural failure. Maintenance assumed control of the aircraft and the subsequent write up of the defect.

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Original NASA ASRS Text

Title: After landing the Captain of a B757 is informed by the 2L Flight Attendant that a piece of aircraft flew off during approach. Post flight reveals a 12X20 inch piece of the inboard left slat to be missing.

Narrative: After landing on and safely vacating the runway we were called on inter-phone by the door 2L flight attendant. She indicated that she thought 'a piece of the wing had flown off' during the approach. From the flight deck perspective the approach and landing had been uneventful. The aircraft had normal flight handling characteristics and no observed performance degradation. Throughout the descent and approach all flap placard speeds had been conservatively observed with extensions occurring approximately 10 knots below FM limits. We nevertheless elected to err on the side of caution and contacted maintenance while taxiing to the arrival gate. We informed local maintenance of our specific concerns. Maintenance was ready and waiting at the arrival apron. Subsequently; maintenance personnel met us in the cockpit as we completed our shutdown checklist items. As it turns out; an approximate 12 X 20 inch jagged piece of the upper left inboard slat had ripped of and was indeed missing. In reconstructing the events; the First Officer and I had no recollection of a bird strike. In fact; there was no blood; feathers or other evidence to suggest that such an impact had occurred. The only logical conclusion seems to be that the leading edge somehow suffered an integral honeycomb structural failure. Maintenance assumed control of the aircraft and the subsequent write up of the defect.

Data retrieved from NASA's ASRS site as of July 2013 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.