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ELLIS COUNTY (CBSDFW.COM) – One of two Bell Helicopter employees killed when their experimental chopper crashed Wednesday was identified as Jason Grogan from Euless.

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The former marine was an experimental pilot for the aerospace manufacturer.

Investigators from the National Transportation Safety Board are trying to figure out what caused the helicopter to crash during a test flight, killing Grogan and another pilot onboard.

The NTSB spent the first part of Thursday investigating an area where a charred utility pole from the post-crash fire is located.

Investigators said they’re still in the early stages of the process, and they can’t say for certain what caused the experimental twin-engine 525 Bell Helicopter to crash.  The aircraft went down in a remote field.

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Teams canvassed the crash site Thursday while a helicopter surveyed the area to help with a view from above. Investigators are looking at part numbers and trying to narrow down any signatures associated with specific damage.

John Lovell is the investigator in charge.  He said his team is looking at flight data recorded by Bell that could help pinpoint what went wrong.

“I have another investigator over at Bell Helicopter at plant six, where we’re looking at the data because it was a flight test helicopter, and there was some data that was relayed back, so we’re trying to go through that process,” said Lovell.

Investigators left the crash site Thursday afternoon to go over the flight data at Bell’s headquarters.

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