Caravan 208B
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 100; Flight Crew Total 4800; Flight Crew Type 500
Time Pressure; Troubleshooting; Situational Awareness
Aircraft Equipment Problem Critical; Inflight Event / Encounter Loss Of Aircraft Control
General Maintenance Action
Aircraft
Upon blocking out of parking spot; did a brake check. Entered Taxiway A; winds reported 050/19G33; weight of aircraft 6;700 LBS. Just past Taxiway B; aircraft started to veer to left. [I] used right brake to try and correct back to centerline of taxiway A; no response from brake. Used both brakes to try and bring aircraft to a stop in addition to reverse throttle. Aircraft continued to veer 90 degrees to the left. Shutdown engine; advised Tower. [I] did shutdown checklist; chocked aircraft; and inspected brakes and hydraulic reservoir. Everything appeared to be OK. No trace of skid marks from braking. Company flew in with maintenance team and tow bar. Master cylinders removed for inspection upon return to our maintenance base. New master cylinders installed. [I am] waiting outcome of master cylinder inspection at headquarters. Not able to duplicate although Chief Pilot mentioned in debrief that the aircraft has a history of unexplained brake failures with deviations/excursions from taxiways and runways.
A C208B brake system failed after taxi-out resulting in a hard left turn; so the pilot used all available braking to bring the aircraft to a stop. Previous brake failures were reported.