On October 9, 1992, a Bell 47G-3B-1 (registration N31FG) operated by Speth, Stephen F. was involved in an aviation accident near Centre, AL. Investigators recorded the probable cause as: THE PILOT'S FAILURE TO MAINTAIN MAIN ROTOR RPM, WHICH RESULTED IN AN IN FLIGHT LOSS OF CONTROL AND COLLISION WITH TERRAIN. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
While performing a turn to reverse direction, an agricultural helicopter pilot allowed main rotor RPM to decay, lost control, and the helicopter crashed after a second RPM decay, severing the tail boom.
Accident Sequence
An agricultural helicopter was involved in an accident while performing a maneuver to reverse direction. During the turn, the pilot allowed the main rotor RPM to decay, resulting in a loss of control. The helicopter subsequently bounced into a field. After becoming airborne again, the RPM decayed a second time, leading to another loss of control. The helicopter then crashed into the field. During the impact, the tail boom was severed by the main rotor blades.
Pilot Report
The pilot reported that there was no mechanical malfunction or failure with the helicopter during the accident flight. The entire sequence was attributed to the pilot's actions during the maneuver.