WPR22LA323

During an instructional flight, the student pilot reduced engine power to idle and applied the brakes as the airplane taxied toward the end of the runway. However, the airplane did not respond to this brake application. The flight instructor assumed control of the airplane and applied brakes, but the airplane still did not respond. While the flight instructor was attempting to mitigate the situation, the airplane exited the right side of the taxiway and impacted a ditch. Examination of the airplane’s brake system revealed a leak on both main landing gear brake caliper O-ring seals. Both brake calipers were removed and disassembled, and both O-ring seals were flattened, consistent with excessive use and wear. The flattened O-ring seals prevented the proper seal within the brake calipers, which resulted in the complete loss of brake fluid. The complete loss of brake fluid prevented the use of the airplane brakes, which caused a subsequent loss of directional control.

On August 30, 2022, about 0915 mountain daylights time, a Cessna 182, N3094Q, was substantially damaged when it was involved in an accident near Tooele, Utah. The flight instructor and student pilot were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The flight instructor reported that, after conducting a preflight inspection, they taxied the airplane to runway 17 for a local instructional flight. While approaching the end of the taxiway, the student pilot reduced engine power to idle and applied the brakes, but the airplane did not respond to the brake application. The flight instructor assumed control of the airplane and applied the brakes, but the airplane still did not respond. While the flight instructor was attempting to mitigate the situation with the parking brake handle and rudder, the airplane exited the right side of the taxiway and impacted a ditch. Postaccident examination showed bending of the right horizontal stabilizer as well as bending of the right elevator about midspan. Flight control continuity was established from all primary flight control surfaces to the cockpit controls. Examination of the airplane’s brake system revealed that, when the brakes were activated using the rudder pedals, no resistance or pressure was felt on both sets of rudder pedals. Both brake master cylinders were void of fluid, and a liquid consistent with brake fluid was observed leaking from both main landing gear brake caliper O-ring seals. The left and right brake calipers were removed and disassembled. Both O-ring seals were flattened, consistent with excessive use and wear. According to the mechanic, the flattened O-ring seals prevented the proper seal within the brake calipers, resulting in brake fluid leaking. A review of the airplane’s maintenance records did not show that any maintenance had been performed on the brake calipers.