Narrative:

Upon landing, which I considered to be a firm, but normal landing, the aircraft touched down on the 2 main gear. The power was at idle and the aircraft appeared to be aligned with the centerline of the runway. Subsequently, the right wing appeared to rise, and I felt a force towards the left side of the airplane. At that moment the flap lever slammed to the down position (flap up position). The pilot tried to correct to the right by applying more right rudder and right aileron. The aircraft was non responsive, and the pilot could not maintain directional control. The aircraft kept drifting to the left and came to rest approximately 50 ft north of the runway in the grass. The runway used was runway 12 and the wind was approximately 160 degrees at 12-15 KTS. Approximately 5 mins after myself and the pilot exited the aircraft, an onlooker arrived at the scene with part of the main gear that he retrieved from the runway. Contributing factors could be from mechanical windshear/turbulence, caused by hangars and trees in close proximity to runway. Later, I gathered information from the local pilots concerning this phenomena. Apparently, the point at where we touched down on the runway is known to have windshear and turbulence -- so much, that the local pilots all know to land before or after that point. I believe there should be a published NOTAM regarding that windshear area, or a windsock should be placed there. It is also possible that the landing gear mechanically failed.

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Original NASA ASRS Text

Title: RWY EXCURSION AFTER A BE23 SUNDOWNER PLT LOSES CTL OF HIS ACFT ON THE ROLLOUT AFTER LNDG WITH A XWIND CONDITION, RWY 12 AT 00R, TX.

Narrative: UPON LNDG, WHICH I CONSIDERED TO BE A FIRM, BUT NORMAL LNDG, THE ACFT TOUCHED DOWN ON THE 2 MAIN GEAR. THE PWR WAS AT IDLE AND THE ACFT APPEARED TO BE ALIGNED WITH THE CTRLINE OF THE RWY. SUBSEQUENTLY, THE R WING APPEARED TO RISE, AND I FELT A FORCE TOWARDS THE L SIDE OF THE AIRPLANE. AT THAT MOMENT THE FLAP LEVER SLAMMED TO THE DOWN POS (FLAP UP POS). THE PLT TRIED TO CORRECT TO THE R BY APPLYING MORE R RUDDER AND R AILERON. THE ACFT WAS NON RESPONSIVE, AND THE PLT COULD NOT MAINTAIN DIRECTIONAL CTL. THE ACFT KEPT DRIFTING TO THE L AND CAME TO REST APPROX 50 FT N OF THE RWY IN THE GRASS. THE RWY USED WAS RWY 12 AND THE WIND WAS APPROX 160 DEGS AT 12-15 KTS. APPROX 5 MINS AFTER MYSELF AND THE PLT EXITED THE ACFT, AN ONLOOKER ARRIVED AT THE SCENE WITH PART OF THE MAIN GEAR THAT HE RETRIEVED FROM THE RWY. CONTRIBUTING FACTORS COULD BE FROM MECHANICAL WINDSHEAR/TURB, CAUSED BY HANGARS AND TREES IN CLOSE PROX TO RWY. LATER, I GATHERED INFO FROM THE LCL PLTS CONCERNING THIS PHENOMENA. APPARENTLY, THE POINT AT WHERE WE TOUCHED DOWN ON THE RWY IS KNOWN TO HAVE WINDSHEAR AND TURB -- SO MUCH, THAT THE LCL PLTS ALL KNOW TO LAND BEFORE OR AFTER THAT POINT. I BELIEVE THERE SHOULD BE A PUBLISHED NOTAM REGARDING THAT WINDSHEAR AREA, OR A WINDSOCK SHOULD BE PLACED THERE. IT IS ALSO POSSIBLE THAT THE LNDG GEAR MECHANICALLY FAILED.

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.