The noncertificated pilot reported that, while practicing hovering the helicopter in his yard, the experimental amateur-built helicopter struck a tree with the tail rotor. He added that, the next thing he knew the helicopter developed "a huge vibration suddenly and [he] had no heading control". Subsequently, the helicopter impacted the ground.
The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. The helicopter was destroyed by a post-crash fire.
The pilot reported in the NTSB Pilot/Operator Aircraft Accident/Incident Report form (6120.1) that he should have taken more dual instruction, and he should have chosen a more open area for hover practice.