Primary finding
Probable cause
The failure of the left brake master cylinder and the pilot's inadequate remedial action when the aircraft collided with an embankment during an intentional ground loop.
Investigator assessment
Analysis narrative
During rollout after landing, the pilot determined that the left brake had failed. He attempted an intentional ground loop to avoid a bank by a ditch. The left landing gear collapsed and the left lower wing sustained impact damage when the aircraft impacted the dirt bank. After the accident, the aircraft owner determined that the left brake master cylinder had failed due to internal corrosion.
Source record
Factual narrative
On July 19, 1994, approximately 0820 mountain daylight time, a Grumman G-164B, N48571, sustained substantial damage while landing at a private airstrip near Wilder, Idaho. The commercial pilot, the sole occupant of the aircraft, was uninjured. Visual meteorological conditions prevailed for the flight, which was engaged in aerial application. There was no ELT installed in the aircraft. The pilot stated that during landing the left brake failed. He attempted an intentional ground loop, during which the left wing impacted a dirt bank, bending the wing spar and collapsing the left main landing gear. After the accident, the owner/pilot determined that the left brake master cylinder had failed due to internal corrosion. -