Narrative:

After a routine approach and normal landing; I was unable to maintain runway centerline using the steerable tailwheel. Aircraft departed the runway to the left and stopped in the adjacent grass. No damage to airplane or property was encountered and there were no injuries.I think the mechanism that allows the tailwheel to free-caster (for towing purposes) had engaged thus making the tailwheel unsteerable. In the future; I plan to thoroughly check this during preflight and again prior to each landing.

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Original NASA ASRS Text

Title: The pilot of a tailwheeled aircraft was unable to control the tailwheel steering during landing rollout; resulting in a runway excursion.

Narrative: After a routine approach and normal landing; I was unable to maintain runway centerline using the steerable tailwheel. Aircraft departed the runway to the left and stopped in the adjacent grass. No damage to airplane or property was encountered and there were no injuries.I think the mechanism that allows the tailwheel to free-caster (for towing purposes) had engaged thus making the tailwheel unsteerable. In the future; I plan to thoroughly check this during preflight and again prior to each landing.

Data retrieved from NASA's ASRS site 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.