PLT OF A CANADAIR CL-600 (CHALLENGER 600) RPTS THAT THE L MAIN OUTBOARD TIRE BLEW ON LNDG TOUCHDOWN DUE TO AN ANTI-SKID FAILURE. THERE WAS NO COCKPIT INDICATION OF ANTI-SKID FAULT OR FAILURE.

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PRIOR TO LNDG; BEFORE ALL LNDG CHKS WERE COMPLETED. CLRNC TO LAND WAS GIVEN AND LNDG COMMENCED ON RWY XX. NORMAL LNDG OCCURRED WITH MINIMAL BRAKING APPLIED AFTER FLT/GND SPOILERS AND THRUST REVERSERS DEPLOYED. ONCE THE ACFT WAS PARKED; SHUT DOWN AND SECURED (CHOCKED); LINE CREW INDICATED TO US THAT WE HAD BLOWN A TIRE ON LNDG AT THE POINT OF TOUCHDOWN. WE DID NOT FEEL ANYTHING RELATED TO A BLOWN TIRE ON LNDG. MYSELF; NOR MY CO-CAPT THOUGHT THIS WAS NORMAL. THIS CONCERNED US SOMEWHAT SO WE HAD OUR DIRECTOR OF MAINT LOOK FURTHER INTO THE ISSUE. DUE TO HIS PERSISTENCE WITH THE TROUBLESHOOTING; HE DISCOVERED (WHAT THE BOMBARDIER REP TOLD US) WAS THE FIRST EXAMPLE WHEN AN ANTI-SKID SYSTEM TESTS NORMAL BUT HAS ACTUALLY FAILED. (VERIFIED MULTIPLE TIMES.) WE HAD NO INDICATION IN THE COCKPIT OF A FAILURE WHILE ONE EXISTED. REPAIRS OCCURRED AND PARTS WERE REPLACED. SUBSEQUENT OPS ARE NORMAL.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THEY PERFORMED THE BRAKE ANTI-SKID SYSTEM TEST IN THE COCKPIT OF THE CL-600 ACFT PRIOR TO DEP; WITHOUT ANY FAULT INDICATION. THEY PERFORMED ANOTHER ANTI-SKID SYSTEM TEST AFTER BEING INFORMED THEY HAD A BLOWN L OUTBOARD MAIN TIRE WITH A BIG FLAT SPOT; NO TREAD AND A HOLE IN THE TIRE. AGAIN THE COCKPIT BRAKE ANTI-SKID TEST INDICATED ALL SYSTEMS NORMAL. RPTR STATED THEIR DIRECTOR OF MAINT CONTINUED TO TROUBLESHOOT THIS INCONSISTENCY OF ALL ANTI-SKID TESTS NORMAL; BUT EVERYONE REALIZED THE OUTBOARD TIRE BLEW BECAUSE OF A FAILURE OF THE BRAKE TO RELEASE. RPTR STATED THE CL-600 DOES NOT HAVE AUTO-BRAKES. THEIR DIRECTOR OF MAINT (DOM); DID A WHEEL SPEED SENSOR SPIN-UP TEST AT THE BLOWN L OUTBOARD TIRE AND NOTICED THE BRAKE WOULD NOT RELEASE WHEN HE STOPPED SPINNING THE SENSOR; THIS WOULD INDICATE A SKID CONDITION. BUT THE COCKPIT INDICATION STILL SHOWED A NORMAL; NO FAULT CONDITION. HE SWAPPED THE L OUTBOARD WITH THE LEFT INBOARD WHEEL SENSOR; THINKING THE SENSOR WAS BAD; BUT WHEN HE SPUN-UP THE OUTBOARD SENSOR AT THE INBOARD POSITION AND STOPPED; THE INBOARD BRAKE RELEASED. HE THEN WENT OVER TO THE R MAIN OUTBOARD TIRE AND CHECKED THE WHEEL SENSOR; THE BRAKE WOULD NOT RELEASE. BUT ALL COCKPIT INDICATIONS WERE NORMAL; NO FAULTS. THE DIRECTOR THEN PERFORMED A BITE CHECK OF THE ANTI-SKID COMPUTER CTL BOX. AGAIN; NO FAULTS WERE DISPLAYED AND NONE SHOWED DURING THE WHEEL SENSOR SPIN CHECK. RPTR STATED THERE ARE TWO IDENTICAL PRINTED CIRCUIT BOARDS IN THE ANTI-SKID CTL BOX; ONE FOR THE OUTBOARD MAIN BRAKES AND ONE FOR THE INBOARD. HIS DIRECTOR OF MAINT DECIDED TO SWAP THE TWO INTERNAL PCB'S AND SURE ENOUGH; THE OUTBOARD BRAKES RELEASED; BUT NOT THE INBOARD BRAKES. BUT THE COCKPIT AND CTL BOX CONTINUED TO DISPLAY NORMAL CONDITIONS. THE ANTI-SKID CTL BOX WAS REMOVED AND FOUND TO HAVE A 1981 MANUFACTURING DATE. THEY REPLACED THE BOX AND SENSORS AND ALL BRAKES WERE TESTED AND RELEASED NORMALLY.