What was found
(CAN) DURING PRE-FLIGHT, THE FLIGHT CREW NOTICED A FLUID LEAK FROM THE NR 3 BRAKE ASSEMBLY. TEAR-DOWN OF THE BRAKE ASSEMBLY REVEALED A PISTON SEAL BACK-UP RING FOLDED OVER THE PISTON WHICH CAUSED THE O-RING TO FAIL.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
(CAN) DURING PRE-FLIGHT, THE FLIGHT CREW NOTICED A FLUID LEAK FROM THE NR 3 BRAKE ASSEMBLY. TEAR-DOWN OF THE BRAKE ASSEMBLY REVEALED A PISTON SEAL BACK-UP RING FOLDED OVER THE PISTON WHICH CAUSED THE O-RING TO FAIL.