What was found
ON LANDING ROLL AS THE A/C SLOWED THROUGH 55 KTS BRAKE PRESSURE WAS LOST AND THE THRUST REVERSERS WOULD NOT DEPLOY. THE EMERGENCY BRAKES WERE APPLIED TO STOP THE A/C. AT THAT POINT, THE HYD PRESSURE WAS INDICATING ZERO. WHILE AWAITING PARKING INSTRUCTIONS, THE HYD AND NITROGEN PRESSURE RETURNED TO NORMAL. DURING A POSTFLIGHT INSPECTION THE CREW DISCOVERED THE LEFT AFT SECTION OF THE A/C WAS COVERED IN HYD FLUID. MX DISCOVERED THE PRESSURE LINE TO THE LEFT THRUST REVERSER HAD RUPTURED. THE PRESSURE AND RETURN LINES LEADING TO THE NR 1 ENG THRUST REVERSER WERE REPLACED. NORMAL AND EMERGENCY SYSTEMS FOR THE BRAKES WERE BLED. BOTH LT AND RT ENGINE DRIVEN HYD PUMPS WERE REPLACED AS A PRECAUTION. THE A/C WAS