N9137HCessna 172M · 1975

The student pilot of the high wing airplane was taxiing to the runway for takeoff while the pilot of the low wing airplane was holding short of the taxiway to allow the high wing airplane to pass. The student pilot in the high wing airplane reported applying both brakes to slow and make the turn to the runway, but the brakes did not respond as he had expected, which he verbalized to the flight instructor. Despite the flight instructor’s subsequent application of left brake and rudder control inputs, the airplane veered to the right and the high wing airplane’s right wing passed through the propeller arc of the low wing airplane resulting in substantial damage to the right wing.

The flight instructor onboard the high wing airplane stated that earlier during the taxi, the student pilot had reported that the high wing airplane’s left brake was noticeably “weaker” than the right. The flight instructor advised the student that the airplane typically required more left brake input relative to right brake input, after which the student continued to taxi without further incident. Postaccident examination of the high wing airplane’s braking system revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.