FLT CREW LGT CONDUCTED TAXI TEST OF BRAKING FOR MAINTENANCE BLEW TIRES CAUSING RWY CLOSURE UNTIL TIRE DEBRIS CLEARED.

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THE ACFT WE ENDED UP WITH HAD 2 MAJOR WRITE UPS; WHICH INCLUDED AN OVERPRESSURE IN THE RIGHT ENG; WHICH HAD CAUSED A PRESSURE PANEL TO BLOW; REQUIRING INSPECTION FOR DUCT LEAKAGE; AND A GRABBING LEFT BRAKE; ACCOMPANIED BY A LEAKING BRAKE HYD LINE FOUND BY A MECH ON PREFLT. I WAS TOLD BY THE MECHS THAT THEY HAD FORWARDED AN ESTIMATE OF 2 HRS REPAIR TIME TO MAINT CTL. THE ESTIMATE INCLUDED BLEEDING THE BRAKE SYS; AND A HIGH SPD TAXI TEST. NO DETERMINATION HAD BEEN MADE ON THE ENG PNEUMATIC DUCT AT THAT TIME. I REQUESTED ANOTHER ACFT; AND WAS TOLD NONE WAS AVAILABLE. AT THIS POINT; SINCE WE HAD BEGUN WORK AT XA15 AM; I ASKED MY COPLT TO ESTIMATE THE MAX TIME WE COULD STAY ON DUTY. SHORTLY AFTER THAT; THE MECHS DETERMINED THAT THERE WAS NO LEAKAGE IN THE ENG DUCT; AND THAT THE BRAKES HAD BEEN BLED; AND WOULD SHORTLY BE READY FOR THE TAXI TEST. I VOLUNTEERED TO DO THE TEST SINCE I WOULD HAVE TO FLY THE ACFT; AND I WANTED TO KNOW THEIR PERFORMANCE FOR MYSELF. I REQUESTED THAT THE F/A'S LEAVE THE ACFT BEFORE WE CONDUCTED THE TEST SO THAT THERE WOULD BE NO ONE EXCEPT ESSENTIAL PERSONS ON BOARD. I REQUESTED A RWY AND WAS GIVEN RWY 21R. THE WX WAS CLR--THE RWY WAS DRY. WT WAS 165-170. I CHKED THE BRAKES TO A FULL STOP AT LEAST 3 TIMES DURING THE TAXI. THEY REQUIRED SLIGHTLY HIGHER THAN NORMAL PEDAL PRESSURE; BUT OPERATED SMOOTHLY WHEN THE EXTRA PRESSURE WAS ADDED. WE WERE CLRED ONTO THE RWY AT ABOUT XB30 PM. I RELEASED THE BRAKES AND APPLIED TKOF PWR SO THAT THE MECH COULD CHK THE BLOW OUT PANEL ON THE RIGHT ENG. AT 80 KTS I QUICKLY RETARDED THE THRUST LEVERS TO IDLE AND APPLIED THE BRAKES. THERE WAS NO DECELERATION AT ALL. I ADDED A LITTLE MORE PRESSURE. STILL NO DECELERATION FOR A MOMENT; THEN THE AIRPLANE BEGAN TO DECELERATE; BUT NOT AS FAST AS NORMAL. SHORTLY AFTER THAT I HEARD A LOUD POP FOLLOWED SHORTLY BY AT LEAST 2 MORE. THE ACFT BEGAN TO VIBRATE HEAVILY AND VEERED SLIGHTLY TO THE LEFT. I CORRECTED AND; AS THE ACFT SLOWED; BEGAN A TURN TO ENTER THE HIGH SPD TURNOFF JUST N OF RWY 27. THE ACFT CLRED THE RWY AND THE EMER TRUCKS ARRIVED ALONG SIDE ALMOST IMMEDIATELY; ALERTED BY THE SOUNDS OF THE BLOWING TIRES. THE EMER PERSONNEL INFORMED US THAT THERE WERE SEVERAL TIRES BLOWN AND THAT WE WOULD BE UNABLE TO TAXI. THERE WERE NO INJURIES TO ANYONE AND; FROM WHAT I COULD SEE; THERE WAS NO DAMAGE TO THE ACFT WITH THE EXCEPTION OF THE TIRES. THE RWY WAS CLOSED FOR ABOUT 15 MI; UNTIL THE TIRE DEBRIS COULD BE CLEANED UP. WE LEFT THE ACFT AS SOON AS A TUG WAS HOOKED UP TO IT. DURING THE GND ROLL; AFTER THE FIRST POP INDICATING A BLOWN TIRE; MY THOUGHT IMMEDIATELY WAS THAT THE ANTISKID HAD MALFUNCTIONED. I STARTED TO GLANCE IN THAT DIRECTION; BUT WAS PREVENTED BY THE FACT THAT THE ACFT BEGAN SWERVING TO THE LEFT AND MY ATTN WAS DRAWN TO PREVENTING THAT. AFTER THE LNDG ROLL WAS COMPLETED; I HAD THE TIME TO CHK THE ANTISKID SWITCH AND IT WAS IN THE ON POS AND THE OFF LIGHT WAS OUT. I QUESTIONED MY COPLT ABOUT IT LATER; AND HE REPLIED THAT IT WAS HIS FIRST THOUGHT TOO; AND THAT HE REACHED OVER TO CHK THE SWITCH WITH HIS FINGER TO MAKE SURE THAT IT WAS IN W/O ACTUALLY LOOKING AT IT. HE SAID IT FELT LIKE IT WAS. THE FACT THAT THERE WERE 2 MALFUNCTIONS THAT NEEDED EVALUATION COMPLICATED MY ACTIONS. THE ENG BLEED TEST REQUIRED HIGH EPR; WHILE THE TAXI TEST FOR THE BRAKES COULD HAVE BEEN DONE AT A LOWER SPD THAN I CONDUCTED IT. ATTEMPTING TO SATISFY THE REQUIREMENTS OF 2 TESTS WITH 1 TAXI RUN WAS ANOTHER PIECE OF QUESTIONABLE JUDGEMENT. I HAVE NO DOUBT THAT THERE WAS SOMETHING SERIOUSLY WRONG WITH THE BRAKE SYS ON THIS ACFT. THE LOGBOOK WAS FILLED WITH REPEATED GRIPES AND CHANGED COMPONENTS. BUT I DO BELIEVE THAT; EXCEPT FOR THE FACTORS MENTIONED ABOVE; I MIGHT HAVE DONE THE TEST DIFFERENTLY WITH LESS COSTLY RESULTS TO THE COMPANY.