Incident Overview
A student pilot was practicing a hover with the helicopter positioned 8 to 12 inches above ground level (AGL) when the heel of the right skid made contact with the ground. The Certified Flight Instructor (CFI) reported not noticing any drift or descent prior to the contact; however, upon feeling the ground contact, he assumed control of the helicopter.
Sequence of Events
The CFI immediately applied up collective and left cyclic in an attempt to recover. Despite these inputs, the right skid contacted the ground a second time. The skid then dug into the soft sod, and the helicopter rolled over onto its right side.
Pilot Actions
The CFI stated that he did not observe the helicopter drifting or descending before the initial ground contact. After taking over the controls, his inputs of raising the collective and applying left cyclic were insufficient to prevent the second contact and subsequent rollover.
Outcome
The helicopter rolled over to the right after the skid dug into the soft sod.