A PA28 DAKOTA PVT PLT ALLEGES THAT BRAKE DESIGN AND BREAK IN PROCS DURING TAXI OPS WERE INVOLVED IN HIS DEPARTING THE TXWY AT BMG; IN.

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DAKOTA WENT TO FBO AT MONROE COUNTY ARPT ON JUL/MON/00 FOR ITS ANNUAL INSPECTION. THE CURRENT ANNUAL WAS COMPLETED JUL/FRI/00; AT WHICH TIME THE ACFT WAS DIRECTLY RETURNED TO HANGAR BY THIS WRITER. PART OF THE COMPLETED SVC INCLUDED REPLACEMENT OF THE PARKER-HANNIFIN METALLIC BRAKE PADS SPECIFIED BY PIPER REPLACING PRIOR TO ASBESTOS PRODUCTS. THE MANUFACTURER OF THESE PADS RECOMMENDS A ROUTINE TEMPERING PROC FOR THE PADS PRIOR TO REGULAR USE. THE PROC SPELLED OUT ON THE PRODUCT'S PACKAGING CALLS FOR TAXIING FOR APPROX 1500 FT; AT AN ENG RPM OF 1700; BRAKES APPLIED; TO RESTRICT TAXI SPD TO 5-10 MPH. AFTER THE BRAKE PADS HAVE COOLED THEIR HOLDING CAPACITY IS TO BE CHKED AT STANDARD RUN-UP; WITH THE PROCESS REPEATED IF THERE IS INCOMPLETE HOLDING. AT APPROX XY45 PM ON AUG/WED/00; THIS WRITER REMOVED ACFT FROM THE HANGAR TO COMPLETE THIS PROCESS SO THE ACFT COULD BE SUBSEQUENTLY SCHEDULED FOR FLT. THE BRAKES DURING THE PROC PROPER APPEARED TO BE PROVIDING ADEQUATE REDUCTION OF TAXI SPD AND THE PEDALS SEEMED GENERALLY FIRM. ROUGHLY MIDWAY THROUGH THE PROC THERE WAS SOME LIMITED BRAKE CHATTER FROM STARBOARD BUT IT CEASED WHEN BRAKING PRESSURE WAS EASED. JUST SHORT OF ALPHA 2 PWR WAS PULLED BACK TO IDLE AND THE BRAKES WERE RELEASED WITH THE INTENTION OF LETTING THE ACFT FREE ROLL TO A STOP APCHING THE RWY 17 RUN-UP AREA TO LET THE BRAKES COOL SOMEWHAT AND FOR A 180 DEGS TO RETURN TO HANGAR. BTWN RELEASING THE BRAKES AND GETTING THE RPM BACK TO IDLE ALONG WITH SOME TAILWIND THE ACFT INITIALLY PICKED UP SOME GND SPD. THE ACFT SLOWED BUT IN THIS WRITER'S VIEW WAS CLOSING TOO FAST AND I REAPPLIED THE BRAKES ROUGHLY 150-200 FT S OF THE RWY 17 RUN-UP PAD BUT THERE WAS ZERO BRAKING ACTION. AT ROUGHLY 50 FT FROM THE RUN-UP PAD I STOOD ON THE BRAKES AND ELECTED TO GO INTO THE GRASS RATHER THAN TRY A 180 DEGS ON THE PAD OR VEER L TOWARD THE ACTIVE RWY 17. AT THE N EDGE OF THE TXWY THE ACFT WAS SLOWED TO ROUGHLY A FAST WALK BUT MY POSITIONING WAS ON A SMALL DOWN INCLINE WITH A RUTTED DRAINAGE PATH E TO W. ROUGHLY 30 FT BEYOND THE N EDGE OF THE TXWY THE GRAVITY DOWN ROLL CAUSED THE NOSE GEAR FAIRING TO DIG INTO THE RUT BENDING THAT GEAR'S LOWER L AFT STRUT AND COLLAPSING THE GEAR AFT. THE ENG WAS AT IDLE CUT OFF BUT THE PROP WAS STILL TURNING AND WAS BENT. THE L MAIN WAS ON SOLID GND BUT THE R MAIN SANK IN THE SMALL WASH; I SUSPECT PUSHING THE PERIPHERAL BASE OF THE FAIRING INTO A HOT BRAKE CYLINDER AND/OR CALIPERS AND PADS. I EXITED THE ACFT TO INSPECT THEN CALLED GND TO REQUEST HELP FROM FBO TO GET THE ACFT BACK ON THE TXWY AND BACK TO THE RAMP. APPROX 2-3 MINS AFTER THAT CALL I NOTICED SMOKE FROM UNDER THE R WING AND FOUND FIRE IN AND AROUND THE FAIRING. I CALLED GND AGAIN FOR FIRE ASSISTANCE THEN EMPTIED THE EXTINGUISHER ON IT WHICH HELD FOR ABOUT A MIN. THERE WAS PROBABLY A FURTHER 2-3 MIN PERIOD BEFORE THE FIRE EQUIP ARRIVED. THE FIRE WAS EXTINGUISHED IN 60-90 SECONDS BY THEM BUT BY THEN HAD FULLY BURNED THE R MAIN FAIRING RESINS AND PAINT; PART OF THE TIRE; A ROUGHLY 2-3 FT CIRCULAR HOLE IN THE UNDERSIDE SKIN; THE LOWER PART OF 1 RIB; HAD DEFORMED AND SCORCHED THE OPPOSITE UPPER SKIN; AND DEFORMED THE R FLAP. THERE WAS NO FUEL INVOLVEMENT PROBABLY BECAUSE THE TANKS ARE CARRIED TOPPED AND THEIR MASS RESISTED HEAT SOAKING. THE NOSE GEAR APPEARED TO HAVE LODGED AT A 45 DEG ANGLE WITHOUT PUSHING INTO THE BOTTOM OF THE FUSELAGE EXCEPT AT THE FORWARD CTR INSPECTION PORT. THE REST OF THE ACFT SKIN MADE NO GND OR OTHER CONTACT. NO TXWY LIGHTING WAS INVOLVED. THERE WAS NO PERSONAL INJURY. I PREVIOUSLY SUCCESSFULLY PERFORMED THIS BRAKE TEMPERING PROC WITH P-H PADS MULTIPLE TIMES ON A PIPER LANCE (PA32R-300) OPERATED FOR ABOUT A DECADE. A COMBINATION OF ARPT AND FBO PERSONNEL INSTALLED A USED REPLACEMENT WHEEL ON THE R MAIN; PULLED THE ACFT BACK ONTO THE TXWY; AND USED DOLLIES UNDER THE NOSE GEAR TO GET THE ACFT BACK TO HANGAR. PER INSTRUCTIONS FROM THE FAA RELAYED THROUGH THE TWR MGR THE ACFT WAS LOCKED UP IN HANGAR THAT NIGHT WITH NO ADDITIONAL SVC ATTEMPTED. SELF-EVIDENTLY THE BRAKES OVERHEATED; CAUSING EITHER THE HYD FLUID TO BOIL OR O-RINGS IN EITHER BRAKE CYLINDER FAILED. BRAKED TAXI CONTINUED TOO LONG; OR THE OUTSIDE AIR TEMP PLUS FAIRED GEAR ALLOWED EXCESS HEAT BUILD UP WITH INADEQUATE COOLING. THE ABOVE CONTRIBUTED TO THE INCIDENT BUT WOULD HAVE BEEN MOOT HAD THE MONROE COUNTY TXWY NOT GIVEN WAY TO AN IMPROPERLY LANDSCAPED AND INADEQUATELY MAINTAINED GNDS AREA. THE N END OF RWY 17/35 WAS EXTENDED SEVERAL YRS AGO WITH A FEDERAL GRANT. IN MY VIEW THE GRASS AREAS AT THE PERIPHERY OF THE EXTENDED TXWY WERE NOT PROPERLY SPECIFIED AND COMPLETED. PARKER-HANNIFIN'S GENERIC INSTRUCTIONS FOR THIS PROC WERE INADEQUATE IN ALLOWING FOR THEIR APPLICABILITY TO MULTIPLE ACFT; AND THE PRODUCT PACKAGING SHOULD HAVE CONTAINED CAUTIONS ABOUT THE EFFECTS AND RISKS OF THE PROC. JUDGEMENTALLY; THE CONSEQUENCES COULD HAVE BEEN ELIMINATED IF; 1) THE BRAKING MALFUNCTION(S) HAD BEEN INSTANTLY RECOGNIZED ALLOWING IMMEDIATE ENG CUT OFF; OR 2) IF THE PROC HAD BEEN ADDRESSED INCREMENTALLY BY REDUCING THE BRAKING FORCE AND RELYING ON REPETITIVE OP. THE ACFT INVOLVED IS A DESIGN VARIATION OF A LIGHTER MODEL WITH A MATERIAL INCREASE IN GROSS WT. THE BRAKES; AN OPINION; ARE MARGINAL AT ALL TIMES ON THIS MODEL AND SHOULD HAVE BEEN SPECIFIED AT DESIGN TO GREATER CAPACITY.