Narrative:

Aircraft was on taxiway approaching runway X. The taxiway has a slight downslope toward the runway. The brakes were applied to slow the aircraft preparatory to stopping short of the hold short line. The right brake failed and the left brake caused the aircraft to pull to the left. Power was reduced to idle; however; due to the downslope; the aircraft continued to roll toward the hold short line. Application of the left brake in the absence of the right brake caused the aircraft to pivot to the left off the taxiway by the time the engine was cut off. The right wheel or propeller struck a taxi light. If the taxiway was level or had a slight upslope toward the runway; the aircraft would have stopped short of the hold short line without pivoting off the taxiway.

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Original NASA ASRS Text

Title: C172 PLT REPORTS R BRAKE FAILURE DURING TAXI; CAUSING THE ACFT TO VEER OFF THE TXWY BEFORE THE ENG CAN BE SHUT DOWN.

Narrative: ACFT WAS ON TXWY APCHING RWY X. THE TXWY HAS A SLIGHT DOWNSLOPE TOWARD THE RWY. THE BRAKES WERE APPLIED TO SLOW THE ACFT PREPARATORY TO STOPPING SHORT OF THE HOLD SHORT LINE. THE R BRAKE FAILED AND THE L BRAKE CAUSED THE ACFT TO PULL TO THE L. PWR WAS REDUCED TO IDLE; HOWEVER; DUE TO THE DOWNSLOPE; THE ACFT CONTINUED TO ROLL TOWARD THE HOLD SHORT LINE. APPLICATION OF THE L BRAKE IN THE ABSENCE OF THE R BRAKE CAUSED THE ACFT TO PIVOT TO THE L OFF THE TXWY BY THE TIME THE ENG WAS CUT OFF. THE R WHEEL OR PROP STRUCK A TAXI LIGHT. IF THE TXWY WAS LEVEL OR HAD A SLIGHT UPSLOPE TOWARD THE RWY; THE ACFT WOULD HAVE STOPPED SHORT OF THE HOLD SHORT LINE WITHOUT PIVOTING OFF THE TXWY.

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.