Incident Overview
A certified flight instructor (CFI) and a pilot under instruction (PUI) were conducting external load training in a helicopter. After completing the training exercise, they landed the helicopter in a clear, level area. Both pilots exited the aircraft, disconnected the external load line, and confirmed that the skids were free of any entanglement. They then reentered the helicopter.
Sequence of Events
The PUI began to apply collective pitch to lift the helicopter off the ground. As the helicopter started to ascend, the left skid lifted first, causing the helicopter to roll to the right. Both pilots responded by applying full down collective and full left cyclic inputs. Despite these control inputs, the helicopter continued to roll over onto its right side.
Aircraft Condition
The pilot stated that the helicopter and its engine experienced no mechanical failures or malfunctions during the external load training portion of the flight. The exact cause of the rollover was not determined from the available information.