On December 21, 1992, a Hiller UH-12C (registration N38767) operated by Vintage Props & Jets Inc. was involved in an aviation accident near New Smyrna Bch, FL. Investigators recorded the probable cause as: THE PILOT-IN-COMMAND'S IMPROPER APPLICATION OF CYCLIC AND COLLECTIVE PITCH CONTROL DURING AN AUTOROTATIVE LANDING. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During an autorotative landing demonstration, the helicopter's stinger and tail rotor blades struck the ground and separated after the instructor failed to level the helicopter with cyclic during collective application.
Overview
A flight instructor demonstrating an autorotative landing to a commercial pilot receiving instruction experienced a tail strike during the maneuver. The simulated emergency was initiated while the helicopter was on the base leg of the approach.
Sequence of Events
At approximately 75 feet above ground level (AGL), the instructor began a deceleration. About 10 feet AGL, collective pitch was applied without first leveling the helicopter using the cyclic control stick. The lack of cyclic input resulted in the helicopter's tail stinger and tail rotor blades contacting the ground. The impact caused the tail rotor blades, stinger, and tail rotor gearbox to separate from the helicopter.
Aftermath
Following the separation, the helicopter slid to the right and came to a complete stop on its skids in the grass. The aircraft remained upright and came to rest without further incident.