Narrative:

B757 captain route check, atl-mex, visual approach, ILS/DME runway 5R, mexico city. Wind estimated east at about 8 KTS. There is a note on the 10-0A green page under warning, 'low level windshear of 10-20 KTS at 50-100 ft may occur with calm or light winds, especially on runway 5L/right.' this was briefed on the approach check. Relatively smooth approach. Radar altimeter started counting down 50 ft, 40 ft, 30 ft and about 20 ft the aircraft experienced moderate turbulence. The wings rolled back and forth as I tried to control the aircraft. It was like heavy wake turbulence. The aircraft touched down on centerline in touchdown zone. Landing was firm on mains, nose touchdown controled. Autospoilers probably exaggerated touchdown. Autobrakes were MEL'ed inoperative. At high altitude airports like mex you need ample reverse thrust due to high true airspeed. The only aircraft close to us was a foreign based B737-400 at their maintenance base parked parallel to our landing point. You hate to end a nice flight on a less than perfect note, but it's just a fact that some airports have unusual WX/wind characteristics. I'm not sure what created this sudden jolt of wind, but in retrospect, I would have handled the situation in a similar manner. I always go stand at the door to say goodbye regardless of flight events. The 'a' line and at least 2 other flight attendants I spoke to, asked about the landing and asked about a wingtip strike. I explained the green page/mountain wind situation to them and assured them we did not experience a wingtip strike. 1 passenger I think was a private pilot asked me about the wind and I explained again the possibility of unusual winds and he seemed satisfied and very pleasant. The fact is, some passenger are uncomfortable flying, period. WX and turbulence can exaggerate a situation. The walkaround was normal. As I deplaned in atl, I unexpectedly was asked by a mechanic 'what happened down there,' I asked what he meant and he told me a flight attendant had called atlanta (they stayed over in mex) and said the plane hit a wingtip. He confirmed what I already knew. There was nothing wrong with the plane. I was absolutely stunned that a flight attendant in the back of the plane would bypass 2 veteran capts to notify the company that an airplane was damaged, when in fact it was not. I would never move, or operate an aircraft that was damaged. I am also very concerned that a flight attendant, or any crew member, would discuss something as inaccurate as this with passenger. In addition to the attached report, I wish I had some idea as to the frequency of low level windshear at mexico city. It is difficult to get precise information from individual controllers in mexico. I'll always wonder about the actual winds versus aircraft generated engine turbulence from airline maintenance facility adjacent to the runway. This whole scenario was quite unusual. Compounding the problem with totally inaccurate reports from unqualified people like flight attendants who get scared in WX does not help.

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Original NASA ASRS Text

Title: A B757 CAPT'S RPT ON THE APCH AND LNDG EXPERIENCED THAT APPEARED TO INCORPORATE ALL THE PERSONA OF A WINDSHEAR AND JET BLAST ENCOUNTER FOR THE LAST 20 FT OF THE APCH TO A FIRM LNDG AT MMMX, FO.

Narrative: B757 CAPT RTE CHK, ATL-MEX, VISUAL APCH, ILS/DME RWY 5R, MEXICO CITY. WIND ESTIMATED E AT ABOUT 8 KTS. THERE IS A NOTE ON THE 10-0A GREEN PAGE UNDER WARNING, 'LOW LEVEL WINDSHEAR OF 10-20 KTS AT 50-100 FT MAY OCCUR WITH CALM OR LIGHT WINDS, ESPECIALLY ON RWY 5L/R.' THIS WAS BRIEFED ON THE APCH CHK. RELATIVELY SMOOTH APCH. RADAR ALTIMETER STARTED COUNTING DOWN 50 FT, 40 FT, 30 FT AND ABOUT 20 FT THE ACFT EXPERIENCED MODERATE TURB. THE WINGS ROLLED BACK AND FORTH AS I TRIED TO CTL THE ACFT. IT WAS LIKE HVY WAKE TURB. THE ACFT TOUCHED DOWN ON CTRLINE IN TOUCHDOWN ZONE. LNDG WAS FIRM ON MAINS, NOSE TOUCHDOWN CTLED. AUTOSPOILERS PROBABLY EXAGGERATED TOUCHDOWN. AUTOBRAKES WERE MEL'ED INOP. AT HIGH ALT ARPTS LIKE MEX YOU NEED AMPLE REVERSE THRUST DUE TO HIGH TRUE AIRSPD. THE ONLY ACFT CLOSE TO US WAS A FOREIGN BASED B737-400 AT THEIR MAINT BASE PARKED PARALLEL TO OUR LNDG POINT. YOU HATE TO END A NICE FLT ON A LESS THAN PERFECT NOTE, BUT IT'S JUST A FACT THAT SOME ARPTS HAVE UNUSUAL WX/WIND CHARACTERISTICS. I'M NOT SURE WHAT CREATED THIS SUDDEN JOLT OF WIND, BUT IN RETROSPECT, I WOULD HAVE HANDLED THE SIT IN A SIMILAR MANNER. I ALWAYS GO STAND AT THE DOOR TO SAY GOODBYE REGARDLESS OF FLT EVENTS. THE 'A' LINE AND AT LEAST 2 OTHER FLT ATTENDANTS I SPOKE TO, ASKED ABOUT THE LNDG AND ASKED ABOUT A WINGTIP STRIKE. I EXPLAINED THE GREEN PAGE/MOUNTAIN WIND SIT TO THEM AND ASSURED THEM WE DID NOT EXPERIENCE A WINGTIP STRIKE. 1 PAX I THINK WAS A PVT PLT ASKED ME ABOUT THE WIND AND I EXPLAINED AGAIN THE POSSIBILITY OF UNUSUAL WINDS AND HE SEEMED SATISFIED AND VERY PLEASANT. THE FACT IS, SOME PAX ARE UNCOMFORTABLE FLYING, PERIOD. WX AND TURB CAN EXAGGERATE A SIT. THE WALKAROUND WAS NORMAL. AS I DEPLANED IN ATL, I UNEXPECTEDLY WAS ASKED BY A MECH 'WHAT HAPPENED DOWN THERE,' I ASKED WHAT HE MEANT AND HE TOLD ME A FLT ATTENDANT HAD CALLED ATLANTA (THEY STAYED OVER IN MEX) AND SAID THE PLANE HIT A WINGTIP. HE CONFIRMED WHAT I ALREADY KNEW. THERE WAS NOTHING WRONG WITH THE PLANE. I WAS ABSOLUTELY STUNNED THAT A FLT ATTENDANT IN THE BACK OF THE PLANE WOULD BYPASS 2 VETERAN CAPTS TO NOTIFY THE COMPANY THAT AN AIRPLANE WAS DAMAGED, WHEN IN FACT IT WAS NOT. I WOULD NEVER MOVE, OR OPERATE AN ACFT THAT WAS DAMAGED. I AM ALSO VERY CONCERNED THAT A FLT ATTENDANT, OR ANY CREW MEMBER, WOULD DISCUSS SOMETHING AS INACCURATE AS THIS WITH PAX. IN ADDITION TO THE ATTACHED RPT, I WISH I HAD SOME IDEA AS TO THE FREQ OF LOW LEVEL WINDSHEAR AT MEXICO CITY. IT IS DIFFICULT TO GET PRECISE INFO FROM INDIVIDUAL CTLRS IN MEXICO. I'LL ALWAYS WONDER ABOUT THE ACTUAL WINDS VERSUS ACFT GENERATED ENG TURB FROM AIRLINE MAINT FACILITY ADJACENT TO THE RWY. THIS WHOLE SCENARIO WAS QUITE UNUSUAL. COMPOUNDING THE PROB WITH TOTALLY INACCURATE RPTS FROM UNQUALIFIED PEOPLE LIKE FLT ATTENDANTS WHO GET SCARED IN WX DOES NOT HELP.

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.