On February 27, 2007, a Robinson R22 BETA II (registration N199K) operated by Blue Sky Aviation, Inc. was involved in an aviation accident near Tulare, CA. Investigators recorded the probable cause as: The student pilot's improper use of the collective and cyclic control, which induced a dynamic rollover. Also causal was the certificated flight instructor's inadequate supervision and delayed remedial action. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter experienced a dynamic rollover during a training hover autorotation when the student pilot's control inputs led to a hard touchdown on the left skid.
Background
A certificated flight instructor (CFI) was conducting training for a student pilot seated in the right seat. The purpose of the flight was to practice a hover autorotation.
Accident Sequence
The CFI rolled the throttle toward the idle position to initiate the maneuver. In response, the student pilot immediately raised the collective and did not apply sufficient right pedal correction. The student also made an abrupt left cyclic input, causing the helicopter to drift left. The CFI then assumed control of the flight controls in an attempt to arrest the high rate of descent and regain directional control. Despite the intervention, the helicopter touched down hard on the left skid and subsequently experienced a dynamic rollover.
Findings
The CFI reported no mechanical malfunctions or failures with the helicopter prior to impact.