Primary finding
Probable cause
The pilot not maintaining sufficient altitude to clear an obstruction during the aerial application flight.
Investigator assessment
Analysis narrative
The pilot reported that while conducting agricultural spraying operations he first circled the field to be sprayed and noted a windmill at the south end of the field. He started to spray the field and when conducting a spray pass lined up with the windmill, he pulled up to clear the windmill, but encountered a “pocket of dead air” which resulted in the airplane hitting the windmill. The pilot returned to the airport and upon landing the airplane’s left main landing gear collapsed and the airplane went off the side of the runway. The airplane sustained substantial damage to its fuselage. The pilot reported that there were no mechanical malfunctions or failures of the airplane before the accident.