Approach and Wind Shift
During an approach to land on a flat, clear-cut plateau near a local vineyard, the wind shifted from a headwind to a tailwind. The pilot reported that the airspeed dropped below effective translational lift (ETL), resulting in a loss of lift.
Obstacles and Maneuver
The pilot had noted various obstacles at the approach end of the landing zone: two trees about 50 feet apart, which he intended to fly between; a 6-foot-high mound; followed by a 2-foot hole; then another 2-foot mound; and finally a flat area with no additional obstacles.
To compensate for the loss of lift, the pilot pushed the cyclic forward to regain airspeed and applied cyclic and power to avoid contacting the terrain below the top of the plateau. This maneuver helped gain altitude, placing the helicopter above the plateau but not above the 6-foot mound.
Collision and Roll
As the pilot flared the helicopter over the 6-foot mound, the tail rotor guard struck the top of the mound, causing the helicopter to pitch nose-down. One of the landing gear skids then collided with the 2-foot mound, which broke off the tailboom.
Final Resting Position
After the tailboom separated, the helicopter yawed to the right and began to roll to the left. It came to rest approximately 5 feet from the mound, lying on its left side.