What happened
Prior to the flight, the operator and pilot performed routine servicing on the aircraft in preparation for the upcoming spraying season. As part of this maintenance procedure, hydraulic fluid was added to the left brake assembly. However, the pilot did not purge the system of air after adding the fluid.
During a short test flight following the servicing, the aircraft landed. Upon touchdown, the aircraft veered sharply to the right. It departed the runway surface and entered a soft field, where it flipped over.
The investigation
The investigation focused on the maintenance activities performed prior to the flight. It was determined that hydraulic fluid had been added to the left brake system. The critical finding was that the system was not purged of air after the fluid was added.