LOSS OF ACFT CTL BY TAXIING TFC; A C402 ATX. TXWY EXCURSION. ACFT EVACED ABANDONED DAMAGED.

Narrative

WHILE TAXIING OUT TO RWY 18 AT HENDERSON SKY HARBOR ARPT; WHICH IS DOWNHILL; I HAD THE THROTTLES BACK; TAXIING DOWN CTRLINE. I WAS COMING UP TO THE RUN-UP AREA; SO I APPLIED THE BRAKES; AND NOT A MOMENT LATER; I FOUND MYSELF 90 DEGS TO THE TXWY. WHILE APPLYING OPPOSITE RUDDER AND SOME DIFFERENTIAL PWR; THE ACFT DID NOT RESPONSE TO MY INPUTS; SO I CLOSED THE THROTTLE AND APPLIED FULL BRAKES; BUT NOTHING SEEMED TO HAPPEN. A MOMENT LATER I WAS ON THE SHOULDER OF THE TXWY WITH THE NOSE GEAR OVER A 2 FT EMBANKMENT; WITH THE NOSE GEAR COLLAPSED. I SHUT EVERYTHING DOWN AND SECURED THE ACFT. THEN I WENT BACK; OPENED THE AIRSTAIR DOOR AND GOT EVERYONE OUT OF THE ACFT; MOVED EVERYONE DOWN ABOUT 50 YARDS AWAY ON THE SHOULDER OF THE TXWY; EVERYONE WAS ALL RIGHT AND THEY REMAINED CALM. THE PAX WERE PICKED UP BY COMPANY VAN; AND DEPARTED ON THE NEXT LAUNCH. THE AIRPLANE SAT NOSE DOWN AND THE TAIL IN THE AIR; THE RUDDER STILL FULLY DEFLECTED TO THE R AND THE R RUDDER PEDAL FULLY DEPRESSED. I BELIEVE THAT THE L BRAKE LOCKED UP WHICH PUT ME 90 DEGS TO THE TXWY; AND APPLYING FULL R RUDDER DID NOT HELP BECAUSE THE NOSEWHEEL JUST SKIPPED ACROSS THE GND. MECHANICAL FAILURE CAN BE THE ONLY EXPLANATION. THERE WAS ALSO ANOTHER PLT BEHIND ME AND HE COULD NOT BELIEVE WHAT HE WAS SEEING; ONE MIN I'M ON CTRLINE; NEXT SECOND; I'M 90 DEGS TO THE TXWY HEADING FOR THE SHOULDER AND THE RAVINE.