Bell 47G-2A crash near Nicolett, MN, United States

The pilot reported that the helicopter gained altitude and he started a turn during a low level aerial application maneuver. The turning maneuver did not "feel right." He leveled off and stopped the turn. He lowered the collective and added full throttle. The pilot stated that the helicopter's RPMs were in the bottom of the green arc. The helicopter began losing altitude and impacted tall corn. The pilot indicated that there were no mechanical malfunctions with the helicopter. The helicopter sustained substantial damage when the main rotor separated a section of its tailboom.