What was found
UPON TAXI TO RWY 20 FOR DEPARTURE FROM KPWT AT IDLE RPM (A TWY NE BOUND) LOSS OF BRAKING/STEERING CONTROL, RESULTED IN ACFT VEERING OFF PAVED SURFACE AND INTO THE GRASS ADJACENT TO TWY. ACFT WAS IMMEDIATELY SHUTDOWN AND SECURED. NO CONTACT WITH ANY OBJECT AND NO APPARENT DAMAGE TO EITHER THE ACFT OR ANY ON-AIRPORT OBJECT. ENGINE FOD DAMAGE NOT SUSPECTED DUE TO AN IDLE POWER SETTING, RAPID SHUTDOWN, AND LACK OF LOOSE FOREIGN MATERIAL ON THE SIDE OF THE TWY. PILOT’S RIGHT BRAKE/STEERING PEDAL WAS THE AFFECTED SIDE. ENGINE AND PROP TORQUE (EVEN AT IDLE) IS SIGNIFICANT ENOUGH TO CAUSE THIS WITHOUT THE ABILITY TO COUNTER STEER. A MAINTENANCE WORKER AT THE LOCAL MAINTENANCE FACILITY SECURED A TOW BAR AND WAS ABLE TO TOW THE AIRCRAFT BACK ONTO THE TAXI/RUN UP AREA WITHOUT DIFFICULTY. ACFT WAS SUBSEQUENTLY TOWED AGAIN TO THE GA PARKING AREA AWAITING OEDERED MAINTENANCE INSPECTIONS.