Narrative:

Exceptionally strong gust from a direct crosswind during a windshear event in the flare while in heavy rain. It should be noted that prior to this landing; ATC had broken us off the approach due to an emergency aircraft needing assistance. This emergency aircraft had impacted a landing light with his nosewheel during a landing attempt due to these excessive winds. We were landing on runway xxr. The winds were 350 degrees at 22 KTS gusting to 33 KTS. They had had earlier reports of gusts up to 45 KTS. Our assessment is that the winds were a contributing factor but not the sole cause of the incident. Low ceilings; very heavy rain; windshear and high xwinds were all contributing factors. Aircraft was stable at 1000 ft although the airspeed was 15 KTS fast due to windshear precautions. The gusting wind caused considerable turbulence throughout the entire landing phase but was not severe enough to warrant a go around. The extra 15 KTS we carried may very well have saved us. The winds were direct crosswind at 22 KTS gusting to 33 KTS. These winds exceeded our old limitations but not the new limitations currently in effect. The aircraft was in a crab until approaching the flare. Captain applied left rudder to take out some of the crab. As he did; the right wing lifted a little and caught a huge gust of wind. The wind kicked up the right wing which then caught the direct force of a 33 KT (or higher) gust. We exceeded 30 degrees of bank and were concerned about the wingtip hitting the runway. An overcorrection was applied and the aircraft rapidly banked in the opposite direction in excess of 30 degrees bank while another gust hit us and a windshear caused the airspeed to drop about 15-20 KTS. Again the aircraft was over-controled and rolled into another left bank in excess of 30 degrees. I felt certain the wingtip was going to impact the runway and braced for the impact. This involuntary bracing caused pain in my lower back and neck that was severe for only about 5 seconds. It is now 12 hours after the incident and I am still very sore and walking slowly. During the excessive oscillations in the flare; the passenger began screaming. Based on the conversations while the passenger were deplaning; it is apparent that everyone thought the airplane was crashing. Our crosswind policy has recently changed allowing us to operate with these gusts. We were legal but not wise. 193 passenger plus a crew of 6 will confirm that the event had occurred. There will likely be letters written about this event. Pushed power up while fighting with the controls to keep the wings from impacting the runway. Once control was regained; the aircraft was allowed to touch down. Immediate directional control was input to keep the aircraft on the runway. Due to the excessive bank angle and pitch oscillations in the flare; it was determined that a go around would have been more dangerous than to continue. Using the windshear precaution procedures allowed us the extra airspeed we so desperately needed during this critical phase. Strongly suggest that the air carrier reinstitute their policy concerning maximum xwinds. The old policy was much safer and would have prevented us from getting into this situation. We were legal to continue using the new policy; but I will never again allow myself to get into these conditions regardless of the policy. Supplemental information from acn 735574: landing runway xxr wind 340 degrees; 22 KTS gusting to 33 KTS; very strong gusty crosswind. Upon normal flare and xctl for crosswind landing; strong gust rolled aircraft quickly to left; immediately corrected with right aileron input. This rolled over to right to then back to left followed by firm landing as we rolled back right. These oscillations appeared to almost catch the wingtip. Upon discussion with training; appears to be an aerodynamic problem with airflow separation with flaps 30 degrees and aggressive aileron input leading to pilot induced oscillations.

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Original NASA ASRS Text

Title: B757 FLT CREW REPORTS PILOT INDUCED OSCILLATIONS DURING THE LANDING FLARE IN STRONG GUSTY CROSSWINDS.

Narrative: EXCEPTIONALLY STRONG GUST FROM A DIRECT XWIND DURING A WINDSHEAR EVENT IN THE FLARE WHILE IN HVY RAIN. IT SHOULD BE NOTED THAT PRIOR TO THIS LNDG; ATC HAD BROKEN US OFF THE APCH DUE TO AN EMER ACFT NEEDING ASSISTANCE. THIS EMER ACFT HAD IMPACTED A LNDG LIGHT WITH HIS NOSEWHEEL DURING A LNDG ATTEMPT DUE TO THESE EXCESSIVE WINDS. WE WERE LNDG ON RWY XXR. THE WINDS WERE 350 DEGS AT 22 KTS GUSTING TO 33 KTS. THEY HAD HAD EARLIER RPTS OF GUSTS UP TO 45 KTS. OUR ASSESSMENT IS THAT THE WINDS WERE A CONTRIBUTING FACTOR BUT NOT THE SOLE CAUSE OF THE INCIDENT. LOW CEILINGS; VERY HVY RAIN; WINDSHEAR AND HIGH XWINDS WERE ALL CONTRIBUTING FACTORS. ACFT WAS STABLE AT 1000 FT ALTHOUGH THE AIRSPD WAS 15 KTS FAST DUE TO WINDSHEAR PRECAUTIONS. THE GUSTING WIND CAUSED CONSIDERABLE TURB THROUGHOUT THE ENTIRE LNDG PHASE BUT WAS NOT SEVERE ENOUGH TO WARRANT A GAR. THE EXTRA 15 KTS WE CARRIED MAY VERY WELL HAVE SAVED US. THE WINDS WERE DIRECT XWIND AT 22 KTS GUSTING TO 33 KTS. THESE WINDS EXCEEDED OUR OLD LIMITATIONS BUT NOT THE NEW LIMITATIONS CURRENTLY IN EFFECT. THE ACFT WAS IN A CRAB UNTIL APCHING THE FLARE. CAPT APPLIED L RUDDER TO TAKE OUT SOME OF THE CRAB. AS HE DID; THE R WING LIFTED A LITTLE AND CAUGHT A HUGE GUST OF WIND. THE WIND KICKED UP THE R WING WHICH THEN CAUGHT THE DIRECT FORCE OF A 33 KT (OR HIGHER) GUST. WE EXCEEDED 30 DEGS OF BANK AND WERE CONCERNED ABOUT THE WINGTIP HITTING THE RWY. AN OVERCORRECTION WAS APPLIED AND THE ACFT RAPIDLY BANKED IN THE OPPOSITE DIRECTION IN EXCESS OF 30 DEGS BANK WHILE ANOTHER GUST HIT US AND A WINDSHEAR CAUSED THE AIRSPD TO DROP ABOUT 15-20 KTS. AGAIN THE ACFT WAS OVER-CTLED AND ROLLED INTO ANOTHER L BANK IN EXCESS OF 30 DEGS. I FELT CERTAIN THE WINGTIP WAS GOING TO IMPACT THE RWY AND BRACED FOR THE IMPACT. THIS INVOLUNTARY BRACING CAUSED PAIN IN MY LOWER BACK AND NECK THAT WAS SEVERE FOR ONLY ABOUT 5 SECONDS. IT IS NOW 12 HRS AFTER THE INCIDENT AND I AM STILL VERY SORE AND WALKING SLOWLY. DURING THE EXCESSIVE OSCILLATIONS IN THE FLARE; THE PAX BEGAN SCREAMING. BASED ON THE CONVERSATIONS WHILE THE PAX WERE DEPLANING; IT IS APPARENT THAT EVERYONE THOUGHT THE AIRPLANE WAS CRASHING. OUR XWIND POLICY HAS RECENTLY CHANGED ALLOWING US TO OPERATE WITH THESE GUSTS. WE WERE LEGAL BUT NOT WISE. 193 PAX PLUS A CREW OF 6 WILL CONFIRM THAT THE EVENT HAD OCCURRED. THERE WILL LIKELY BE LETTERS WRITTEN ABOUT THIS EVENT. PUSHED PWR UP WHILE FIGHTING WITH THE CTLS TO KEEP THE WINGS FROM IMPACTING THE RWY. ONCE CTL WAS REGAINED; THE ACFT WAS ALLOWED TO TOUCH DOWN. IMMEDIATE DIRECTIONAL CTL WAS INPUT TO KEEP THE ACFT ON THE RWY. DUE TO THE EXCESSIVE BANK ANGLE AND PITCH OSCILLATIONS IN THE FLARE; IT WAS DETERMINED THAT A GAR WOULD HAVE BEEN MORE DANGEROUS THAN TO CONTINUE. USING THE WINDSHEAR PRECAUTION PROCS ALLOWED US THE EXTRA AIRSPD WE SO DESPERATELY NEEDED DURING THIS CRITICAL PHASE. STRONGLY SUGGEST THAT THE ACR REINSTITUTE THEIR POLICY CONCERNING MAX XWINDS. THE OLD POLICY WAS MUCH SAFER AND WOULD HAVE PREVENTED US FROM GETTING INTO THIS SITUATION. WE WERE LEGAL TO CONTINUE USING THE NEW POLICY; BUT I WILL NEVER AGAIN ALLOW MYSELF TO GET INTO THESE CONDITIONS REGARDLESS OF THE POLICY. SUPPLEMENTAL INFO FROM ACN 735574: LNDG RWY XXR WIND 340 DEGS; 22 KTS GUSTING TO 33 KTS; VERY STRONG GUSTY XWIND. UPON NORMAL FLARE AND XCTL FOR XWIND LNDG; STRONG GUST ROLLED ACFT QUICKLY TO L; IMMEDIATELY CORRECTED WITH R AILERON INPUT. THIS ROLLED OVER TO R TO THEN BACK TO L FOLLOWED BY FIRM LNDG AS WE ROLLED BACK R. THESE OSCILLATIONS APPEARED TO ALMOST CATCH THE WINGTIP. UPON DISCUSSION WITH TRAINING; APPEARS TO BE AN AERODYNAMIC PROB WITH AIRFLOW SEPARATION WITH FLAPS 30 DEGS AND AGGRESSIVE AILERON INPUT LEADING TO PLT INDUCED OSCILLATIONS.

Data retrieved from NASA's ASRS site as of January 2009 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.