Narrative:

While on final approach at 170 KIAS and 2500 ft MSL; we lowered gear and extended flaps from 15 to 20 units. Le flap light and le slat asym EICAS message illuminated. We declared an emergency and executed a missed approach. The tower issued us a heading and climb to 2000 ft. Upon switching to departure control; the controller gave us an urgent traffic call with climb and new heading. We saw some traffic and never received a TA or RA. After completing the QRH procedures we were vectored to an ILS. Emergency equipment was standing by otherwise landing and rollout were uneventful.

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Original NASA ASRS Text

Title: A B767-300's EICAS annunciated LE SLAT ASYM and the LE light illuminated at 2;500' An emergency was declared; a go around executed and after QRH procedures completes an uneventful landing followed.

Narrative: While on final approach at 170 KIAS and 2500 FT MSL; we lowered gear and extended flaps from 15 to 20 units. LE flap light and LE SLAT ASYM EICAS message illuminated. We declared an emergency and executed a missed approach. The Tower issued us a heading and climb to 2000 FT. Upon switching to Departure Control; the Controller gave us an urgent traffic call with climb and new heading. We saw some traffic and never received a TA or RA. After completing the QRH procedures we were vectored to an ILS. Emergency equipment was standing by otherwise landing and rollout were uneventful.

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.