Narrative:

Upon touchdown on runway 16L at slc, we experienced a violent shimmy reaction in the aircraft. As a response, I stowed the ground spoilers and shimmying stopped. Later in rollout, deployed ground spoilers and shimmying did not recur. Duration of shaking was 3-5 seconds. When blocked in at the gate and advised maintenance of shimmying, maintenance advised us of a broken trailing edge flap on the left wing. Supplemental information from acn 460337: cleared for a visual approach and told to follow an aircraft on a left base. Separation was 4 mi. Configured for a 40 degree flaps landing. All flap movement seemed normal. We increased our separation and were cleared to land. At approximately 400 ft AGL, the winds changed from a 20 KT headwind to a 4 KT tailwind. At approximately 50 ft, the aircraft dipped left wing low, which I thought may have been from turbulence from the preceding aircraft. The wings were leveled and the flare and touchdown were normal. Not knowing the cause of the shaking or suspecting a flap problem, the flaps were retracted during taxi in. At the gate, the mechanic informed us about damage to the left flap.

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Original NASA ASRS Text

Title: A B737-800 ENCOUNTERS WINDSHEAR AT 50 FT AGL AND PERFORMS WHAT IS CONSIDERED A NORMAL RECOVERY AND TOUCHDOWN. AT THE GATE, MAINT FINDS A DAMAGED L TRAILING EDGE FLAP, SLC, UT.

Narrative: UPON TOUCHDOWN ON RWY 16L AT SLC, WE EXPERIENCED A VIOLENT SHIMMY REACTION IN THE ACFT. AS A RESPONSE, I STOWED THE GND SPOILERS AND SHIMMYING STOPPED. LATER IN ROLLOUT, DEPLOYED GND SPOILERS AND SHIMMYING DID NOT RECUR. DURATION OF SHAKING WAS 3-5 SECONDS. WHEN BLOCKED IN AT THE GATE AND ADVISED MAINT OF SHIMMYING, MAINT ADVISED US OF A BROKEN TRAILING EDGE FLAP ON THE L WING. SUPPLEMENTAL INFO FROM ACN 460337: CLRED FOR A VISUAL APCH AND TOLD TO FOLLOW AN ACFT ON A L BASE. SEPARATION WAS 4 MI. CONFIGURED FOR A 40 DEG FLAPS LNDG. ALL FLAP MOVEMENT SEEMED NORMAL. WE INCREASED OUR SEPARATION AND WERE CLRED TO LAND. AT APPROX 400 FT AGL, THE WINDS CHANGED FROM A 20 KT HEADWIND TO A 4 KT TAILWIND. AT APPROX 50 FT, THE ACFT DIPPED L WING LOW, WHICH I THOUGHT MAY HAVE BEEN FROM TURB FROM THE PRECEDING ACFT. THE WINGS WERE LEVELED AND THE FLARE AND TOUCHDOWN WERE NORMAL. NOT KNOWING THE CAUSE OF THE SHAKING OR SUSPECTING A FLAP PROB, THE FLAPS WERE RETRACTED DURING TAXI IN. AT THE GATE, THE MECH INFORMED US ABOUT DAMAGE TO THE L FLAP.

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.