LOGAN, W.Va. (AP) — A helicopter that crashed during an annual reunion for helicopter enthusiasts was on its last planned flight of the day, a federal agency investigating the accident said Friday.

The National Transportation Safety Board said all six people aboard — the pilot and five passengers, two of whom were pilot-rated — were killed Wednesday. They have not been identified.

Rides on the Vietnam-era Bell UH-1B “Huey” helicopter were offered by the organizer of the reunion, MARPAT Aviation, the NTSB said. The flight route was different from the tour paths that had been flown previously Wednesday, the agency said in a statement on the investigation.

The flight departed Logan County Airport and crashed about 3.7 miles (6 kilometers) northeast of the airport just before 5 p.m. Much of the wreckage was consumed in a fire after the crash, the agency said.

The helicopter didn’t have a cockpit voice recorder or a flight data recorder, which weren’t required, the statement said.

Investigators were expected to remain on the scene for five to seven days and issue a preliminary report within about 15 days after the crash.

During the reunion event, visitors could sign up to ride or fly the historic helicopter, described by organizers as one of the last of its kind still flying.

The helicopter was flown by the 114th Assault Helicopter Company, “The Knights of the Sky,” in Vinh Long, Vietnam, throughout much of the 1960s, according to MARPAT. After the Huey returned to the U.S. in 1971, the website says, it was featured in movies like “Die Hard, “The Rock” and “Under Siege: Dark Territory.”

The crash was near the Battle of Blair Mountain historic sites, where a deadly clash erupted a century ago as thousands of coal miners marched to unionize in West Virginia.

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