Accident Details
The pilot and an observer were conducting a power line patrol flight in a helicopter. The flight proceeded southbound. They approached an area where the power lines under inspection were approximately 23 feet above ground level (AGL). This set of lines was crossed by another set of power lines oriented in an east-west direction. The crossing power lines were about 45 feet AGL, and they included two static lines positioned roughly 15 feet higher, at approximately 60 feet AGL.
Sequence of Events
Before reaching the perpendicular crossing, there was a prominent marker on the fourth pole north of the higher lines. This marker warned of the crossing power lines 1000 feet ahead. As the helicopter was crossing the perpendicular lines, the right skid became entangled with the north static line. The helicopter then nosed down and collided with the lower set of lines that were being inspected. Subsequently, it crashed to the ground and burned. The helicopter was extensively damaged by the ground fire that followed.
Investigation Findings
During the investigation, no evidence of any preimpact mechanical part failure or malfunction was found. The focus of the inquiry was on the circumstances of the entanglement and subsequent crash.