DENVER (AP) – The Federal Aviation Administration has grounded more than 300 Enstrom helicopters nationwide until they can be inspected for possible cracks like the one that may have caused a crash last month that killed two people in Erie.

In an emergency directive issued Thursday, the FAA said that the investigation into the Jan. 26 crash at the Erie Municipal Airport indicates the helicopter’s rotor blade came off because of a crack in the spindle, which holds the rotor blade in place on top of the helicopter.

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The crash, which involved a 30-year-old Enstrom 280FX, killed flight instructor Alex Viola, 23, of Arkansas City, Kansas and student pilot Amy Wood, 25, of Boulder.

Amy Wood (credit: CBS)

Amy Wood (credit: CBS)

A witness told investigators that she saw it landing at what seemed to be a steep angle and that she heard a loud “pop” and then saw the rotor blades coming off.

The investigation into the Colorado crash is expected to take several more months to complete, but the FAA sometimes issues such emergency directives when it finds a condition that might affect the immediate safety of aircraft, agency spokesman Lynn Lunsford said.

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The FAA order applies to 323 Enstrom helicopters in a range of models that are registered in the United States. Police and the military in Thailand, Japan and Indonesia also use the same type of aircraft, according to Enstrom’s website.
The FAA says owners should not fly the helicopters until having an experienced agency inspector perform an X-ray-like test called a magnetic particle inspection to look for cracks in spindles that have 5,000 hours or more of use. If a crack is found, the FAA says it must be replaced before the helicopter is flown.

The FAA directive largely mirrors a service bulletin by Michigan-based Enstrom to its operators worldwide on Wednesday, although the company gave operators some leeway to fly aircraft to service centers in order to be inspected.

While the company is taking the issue seriously, president Tracy Biegler said there’s no evidence cracks have been a problem on any other aircraft in the company’s 55 year history.

The lawyer for Viola’s family, Gary Robb of Kansas City, Missouri, said he plans to sue the company over the crack. He praised the FAA for acting so quickly to try to prevent further crashes.

“This is what this industry and what our regulatory authorities should be doing,” he said.

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