Incident Summary
A pilot conducting an aerial application completed spraying a field and was returning to a private airstrip to reload the hopper and refuel. During the return flight, the airplane experienced an unusual behavior: the pilot reported that it "felt like it tried to nosedive."
Pilot Actions
Upon sensing the nosedive tendency, the pilot checked the power settings and extended the flaps. The pilot then initiated a forced landing to a field. During the forced landing, the airplane struck a levee and came to rest upright.
Engine Examination
Post-incident examination of the engine revealed that the torsion shaft was fractured at the shear point. No further details about the aircraft type, registration, or injuries were provided in the source.