On August 18, 1993, a Schweizer 269C (registration N95AF) operated by Helicopter Tng Academy Inc. was involved in an aviation accident near Punta Gorda, FL. Investigators recorded the probable cause as: THE PILOT-IN-COMMAND'S IMPROPER USE OF THE FLIGHT CONTROLS (CYCLIC AND COLLECTIVE PITCH) DURING A SIMULATED AUTOROTATION WITH TURN, RESULTING IN AN IN FLIGHT COLLISION WITH TERRAIN WITH THE TAIL SKID AND TAILROTOR BLADES. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a training autorotation with turn, a helicopter's tail skid and rotor blades struck the ground after a 'pop' was heard. The instructor recovered to a hover and landed upright. Post-crash inspection found no preexisting failures.
Incident Summary
A flight instructor (CFI) was demonstrating a simulated autorotation with turn to a rated private pilot. The maneuver involved descending with the engine simulated as failed, then flaring and applying collective pitch to terminate the descent.
Flight Sequence
The flare was initiated at about 50 feet above ground level (AGL). Initial collective pitch was applied when the helicopter reached 15 to 20 feet AGL. At that moment, both crewmembers heard a noise described as a "pop." As the CFI increased collective pitch to terminate the autorotation at a hover, the tail skid and tail rotor blades collided with the ground. The helicopter then began to spin to the right.
Recovery and Landing
The CFI applied left anti-torque pedal and rolled the throttle off to the idle stop. The helicopter came to a complete stop upright on its skids.
Post-Inspection
Examination of the helicopter by an authorized repair station revealed that all damage was a result of ground impact. There was no evidence of any precrash failure or malfunction of the tail rotor gearbox or associated components.