Narrative:

After normal landing, ground loop occurred on rollout approximately 20 mph. Left runway to right after lightly applying right brake. Left wheel struck 4 inch concrete ridge at new taxiway. Possible cause momentary lockup of right brake.

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Original NASA ASRS Text

Title: ACFT EQUIP PROB. BRAKE LOCKUP. RPTR GND LOOPED AT APPROX 20 KTS ON LNDG ROLLOUT. POSSIBLE PLT BRAKE APPLICATION PROB.

Narrative: AFTER NORMAL LNDG, GND LOOP OCCURRED ON ROLLOUT APPROX 20 MPH. LEFT RWY TO R AFTER LIGHTLY APPLYING R BRAKE. L WHEEL STRUCK 4 INCH CONCRETE RIDGE AT NEW TXWY. POSSIBLE CAUSE MOMENTARY LOCKUP OF R BRAKE.

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.