PLT OF SMA UNABLE TO THROTTLE BACK DURING TAXI. BRAKE OVERHEATS AND CATCHES FIRE.

Narrative

AT APPROX XA00 PM I STARTED PREFLTING THE ACFT TO MAKE SURE IT WAS AIRWORTHY. WE LOADED THE PAX AND PROCEEDED WITH THE STARTING CHKLIST. WE STARTED TAXIING FROM THE HYANNIS ARPT OPS BUILDING AT XA15 PM; AT WHICH TIME THE TWR WAS CLOSED. AS I WAS TAXIING DOWN TO THE RUNUP AREA AT THE END OF RWY 24; I NOTICED THAT THE PWR SEEMED TO BE INCREASING BUT THAT THE THROTTLE WAS STILL AS FAR BACK AS IT WOULD GO. I TRIED MOVING THE THROTTLE FORWARD AND BACKWARD AND ADJUSTING THE FRICTION LOCK; BUT NOTHING WORKED. I RELEASED THE PRESSURE ON THE BRAKES AND THE AIRPLANE PICKED UP SPD RAPIDLY SO I WENT BACK ON THE BRAKES AND THE AIRPLANE SLOWED DOWN AGAIN. ONCE AGAIN I TRIED RELEASING THE PRESSURE ON THE BRAKES AND THE AIRPLANE RAPIDLY PICKED UP SPD. AT THIS POINT I LOST THE R BRAKE AND STARTED TURNING TO THE L; SO I PUT ON THE PARKING BRAKE; SHUT DOWN THE ENG AND OPENED THE DOOR AND CLBED OUT. I LOOKED UNDER THE R WING AND NOTICED THE WHEEL ON FIRE AND RAPIDLY GOT EVERYONE OUT OF THE AIRPLANE AND WE STARTED RUNNING AWAY FROM THE AIRPLANE TOWARDS THE FIRE DEPT BACK AT OPS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THE SPD FAIRING AND UNDERSURFACE OF THE WING WERE DAMAGED. ALL WAS REPAIRABLE AND ACFT IS BACK IN SVC AGAIN. MAINT DETERMINED THE THROTTLE LINKAGE HAD BROKEN.