Maule MX-7-235 N235X accident near Ontario, Oregon

Probable cause

A loss of hydraulic fluid and failure of the right brake for reasons that could not be determined due to a lack of available evidence.

NTSB analysis

The pilot reported that, when he applied brakes during the landing roll, there was no pressure on the right brake pedal. The airplane veered left and ground looped, resulting in substantial damage. The pilot reported that he observed hydraulic fluid on the right main landing gear after the accident.

The accident was not reported until several months later. An examination of the parts retained by the pilot’s mechanic, including the brake, brake disc, and fittings did not reveal any preimpact mechanical anomalies or failures that would have precluded normal operation. The hydraulic fluid observed on the landing gear suggests the brake failure may have resulted from a leak at either the hydraulic line or the hydraulic inlet fitting to the brake; however, these items were discarded or replaced before the event was reported and could not be examined. The cause of the leak and right brake failure could not be determined due to a lack of available evidence.

Text from the NTSB. Open the NTSB docket for WPR21LA362 for the full record.