What happened
After completing the spraying of a field, the pilot of the aircraft pulled up and deactivated the spray pump. At that moment, the engine experienced a loss of oil pressure accompanied by a loud noise. Smoke began emitting from the cowling, and the engine lost power while the aircraft was approximately 50 feet above the ground.
The pilot performed a forced landing into a cotton field. During the course of the landing roll, the airplane moved through small trees and brush before coming to a final stop across a ditch. The occupants were not injured.
The investigation
An examination of the engine identified that the engine had suffered lubrication distress affecting the number 2 connecting rod bearing and journal. The oil supply for the number 2 connecting rod was provided by the number 2 main bearing. Investigators determined that the number 2 main bearing had shifted within the crankcase bearing saddle, which resulted in a restriction of the oil feed to the number 2 connecting rod. This restriction caused the failure of the number 2 connecting rod.