The 2015 crash of a helicopter at the Erie airport, which left two people dead, was caused by an in-flight break-up of the aircraft’s rotor system prompted by undetected fatigue cracking, the National Transportation Safety Board says.
Specifically, federal investigators zeroed in on the chopper’s No. 2 main rotor spindle — an integral part of the rotor system that buoys the blades of the helicopter — as the primary culprit.
In its final report on the crash, released late last month, the NTSB also cited the Enstrom 280FX’s design as a contributing factor to the helicopter’s crash.
Helicopter flight instructor Alex Viola, a 23-year-old from Arkansas City, Kan., and student Amy Wood, 25, of Boulder, died in the Jan. 26, 2015, crash. The helicopter was registered to New Course Aviation Company and operated by Mountain One Helicopters, according to the NTSB.
Mountain One Helicopters said after the crash that Viola was an instructor for the company and that Wood was working on getting her private license, The Daily Camera reported.
The NTSB said the helicopter — manufactured in 1985 — was on final approach to land when one of the chopper’s three main rotor blades separated, causing the in-flight break up. A witness told investigators she heard a loud “pop” before seeing the helicopter start to rotate as a blade came off the aircraft.
“Metallurgical analysis of the fractured spindle revealed signatures consistent with a fatigue crack initiating from multiple origins that propagated across 92 percent of the spindle cross-section,” the report said. “The remaining 8 percent of the fracture surface exhibited signatures consistent with overload.”