Date: 201705
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Cessna 210 Centurion / Turbo Centurion 210C; 210D
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Personal
Flight phase: Taxi
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Normal Brake System
Component problem: Failed
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Private
Human factors: Workload; Troubleshooting; Situational Awareness
Anomaly: Aircraft Equipment Problem Less Severe; Ground Excursion Taxiway
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action; General Maintenance Action
Contributing factors: Procedure; Aircraft
Primary problem: Aircraft

Narrative: The purpose of this flight was to test the recently serviced brakes which had been serviced at the request of the owner/operator of the aircraft. (Both right and left calipers had shown evidence of leaking hydraulic fluid; and it just made sense to replace the pads following caliper service.) A second purpose was to check the full power fuel flow to the engine which had also been adjusted.Taxi from the FBO ramp to [the runway] via A; C; D; and H was without incident and the brakes were tested. However; no high speed testing is possible while taxing an aircraft.Take off and flight were without incident; flew a short flight round trip to a local airport to obtain a straight-in to Runway 31. Fuel flow performance was fully verified on takeoff and during flight. The aircraft was cleared for straight in 31 approach about XA15 from roughly over the lake (west) with a final call required 5 miles straight-in. Final call was made about XA20 at 5 miles with clearance to land issued by the tower.Landing was uneventful - except for the gusty winds down the Runway. Hard breaking was applied at about taxiway G in order to 'speed-test' the brakes. The brakes grabbed as expected; and within seconds the right brake suddenly failed - probably about taxiway F. Immediate call was made to the tower stating the (right) brake had failed. Stopping and controlling the left-turn tendency of the aircraft became of major concern. At no time was control of the aircraft lost. The aircraft was at slow taxi speed by the time it entered the intersecting area of Runway 17/35 and 31/13; however; the aircraft did not want to turn to the right (into the wind); so rather than shut the aircraft down on the only useable runway; the aircraft was allowed to roll left onto and along Runway 17/35. A call was made to the tower that the aircraft would be 'shut down here and then towed.' With the aircraft now clear of Runway 31/13 and heading south along Runway 17/35; shut down of the engine was initiated. At this point in time; a wind gust 'weather-vaned' the aircraft off of the hard surface onto the grassy area on the east side of runway 17/35. Sufficient control of the aircraft was maintained so that the left main did NOT hit the 'yellow/orange' runway light located nearby. It should be noted that had braking been applied; the left brake action would have probably pulled the aircraft into the Runway light (plus the propeller was still 'windmilling') so the conscience decision was made to allow the aircraft to come to a halt on its own. The owner/operator knew by this time that no damage would occur to aircraft or Runway environment.Further inspection by mechanic and owner/operator showed no damage to the aircraft. Hydraulic fluid was leaking from the right caliper signifying a blown O-ring.




Synopsis: A C210 pilot conducted a post maintenance test flight following fuel control and brake maintenance. After landing; hard braking caused an O-ring to fail; so the pilot safely exited the runway onto an infield area which resulted in no damage.