Narrative:

During the taxi out to runway 16 at ofp, I experienced a right brake failure. At the time, I was trying to turn right, but the aircraft veered to the left and departed the taxiway. When I realized that we weren't going to stop on the taxiway, I shutdown both engines. This aircraft continued left during the entire event and did not respond to full right rudder or full right brake inputs. The aircraft came to rest about 5-10 ft off the taxiway, in a drainage ditch. The nose gear collapsed and both propellers hit the ground. As far as contributing factors, I have no idea. I was not taxing fast -- just at a brisk walk. I checked for brake response when I started taxing, the preflight was uneventful, and a close examination of the brake lines after the incident found no leaks or cracks. The brake pad on the right showed little wear and some rust, whereas the left was polished and blue from the heat. FAA inspectors dismissed my thought that the left brake locked-up, because it could be rotated after the fact.

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Original NASA ASRS Text

Title: A C414 PLT, TAXIING AT OFP, EXPERIENCED A R BRAKE FAILURE WHICH CAUSED HIM TO DEPART THE TXWY.

Narrative: DURING THE TAXI OUT TO RWY 16 AT OFP, I EXPERIENCED A R BRAKE FAILURE. AT THE TIME, I WAS TRYING TO TURN R, BUT THE ACFT VEERED TO THE L AND DEPARTED THE TXWY. WHEN I REALIZED THAT WE WEREN'T GOING TO STOP ON THE TXWY, I SHUTDOWN BOTH ENGS. THIS ACFT CONTINUED L DURING THE ENTIRE EVENT AND DID NOT RESPOND TO FULL R RUDDER OR FULL R BRAKE INPUTS. THE ACFT CAME TO REST ABOUT 5-10 FT OFF THE TXWY, IN A DRAINAGE DITCH. THE NOSE GEAR COLLAPSED AND BOTH PROPS HIT THE GND. AS FAR AS CONTRIBUTING FACTORS, I HAVE NO IDEA. I WAS NOT TAXING FAST -- JUST AT A BRISK WALK. I CHKED FOR BRAKE RESPONSE WHEN I STARTED TAXING, THE PREFLT WAS UNEVENTFUL, AND A CLOSE EXAMINATION OF THE BRAKE LINES AFTER THE INCIDENT FOUND NO LEAKS OR CRACKS. THE BRAKE PAD ON THE R SHOWED LITTLE WEAR AND SOME RUST, WHEREAS THE L WAS POLISHED AND BLUE FROM THE HEAT. FAA INSPECTORS DISMISSED MY THOUGHT THAT THE L BRAKE LOCKED-UP, BECAUSE IT COULD BE ROTATED AFTER THE FACT.

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.