THE COPLT STATED THAT WHEN HE BEGAN THE APCH TO THE DESTINATION ARPT, THE WEATHER CONDITION WAS HAZY & HE DELAYED HIS DESCENT SLIGHTLY UNTIL HE LOCATED THE ARPT. WHEN HE SAW THE RWY, HE BELIEVED THAT THEY WERE A LITTLE TOO CLOSE, SO HE INDICATED TO THE CAPTAIN THAT HE WOULD LIKE TO MAKE A 360 DEG TURN. AT THAT POINT, THE CAPTAIN ASSUMED CONTROL OF THE ACFT & CONTINUED THE APCH TO RWY 4. ACCORDING TO WITNESSES, THE ACFT TOUCHED DOWNED LONG. ACCORDING TO THE CAPTAIN, HE TRIED SEVERAL APPLICATIONS OF THE NORMAL BRAKING SYS, BUT GOT NO RESPONSE. HE THEN TRIED THE EMERGENCY BRAKES & ASKED THE COPLT TO GET ON THE BRAKES, BUT REPORTED THERE WAS NO BRAKING. SUBSEQUENTLY THE ACFT WENT OFF THE END OF THE RWY, WENT OVER AN EMBANKMENT & HIT A FENCE. IT CAME TO REST ON A 2ND EMBANKMENT WHERE IT EXPLODED & BURNED. TIRE MARKS WITH EVIDENCE OF BRAKING ACTION WERE FOUND STARTING 2377 FT BEYOND THE RWY THRESHOLD. A REQUIRED FIELD LENGTH OF APRX 2600 FT WAS CALCULATED FOR LNDG. NO PREIMPACT PART FAILURE/MALFUNCTION WAS FOUND. VASI LIGHTS WERE INOP.