On June 17, 1993, an Enstrom F28C (registration N200NH) was involved in an aviation accident near Gordon, KY. Investigators recorded the probable cause as: The pilot's failure to maintain terrain clearance while flying at low altitude in a valley, resulting in collision with an unmarked static wire. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter collided with an unmarked static wire approximately 450 feet above ground level while navigating a valley at low altitude. No evasive action was taken before impact, resulting in significant structural damage to the aircraft.
What happened
The helicopter was observed flying at a low altitude down a valley when it struck an unmarked static wire approximately 450 feet above ground level. There were no observations of any evasive maneuvers prior to the collision with the wire.
The investigation
Examination of the wreckage revealed that the static wire had made contact with the nose of the helicopter, specifically near the nose landing light. This impact caused the main rotor head to separate from the driveshaft, which in turn severed the tail boom.
Findings
An aeronautical sectional chart depicting the presence of wires was found within the wreckage, indicating that the hazard was known but not avoided during flight.
Probable cause
The pilot's failure to maintain terrain clearance while flying at low altitude in a valley, resulting in collision with an unmarked static wire.