Narrative:

Upon landing, aircraft turned abruptly left and departed the runway surface. Event occurred so fast and so abruptly, full right rudder had no effect.

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Original NASA ASRS Text

Title: A GA CFI LOSES CTL OF HIS AFT DURING THE INITIAL PART OF HIS LNDG ROLL, EXPERIENCING A RWY EXCURSION AT POC, CA.

Narrative: UPON LNDG, ACFT TURNED ABRUPTLY L AND DEPARTED THE RWY SURFACE. EVENT OCCURRED SO FAST AND SO ABRUPTLY, FULL R RUDDER HAD NO EFFECT.

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.