COSBY, Tenn. (WATE) — A lengthy investigation is underway into the cause of a deadly helicopter crash in Sevier County.

According to a preliminary report from the Federal Aviation Administration, a Robinson R-44 helicopter received “substantial” damage after it “crashed east of the (Gatlinburg Pigeon Forge Airport) airport in the foothills of the mountains for unknown reasons.”

On Wednesday, the Sevier County Sheriff confirmed one person died in the crash.

In the FAA’s report, the pilot was listed as the person who died. The passenger in the crash suffered serious injuries. Neither name was released.

The crash happened near Apple Tree Lane just off of Highway 321, near the Sevier County-Cocke County line.

Rachel Koehane, a resident who lives on Apple Tree Lane, said she wasn’t at home at the time of the crash, but her son was.

All of a sudden, she was getting texts and phone calls asking if her family was OK. She had to call her son, who was home at the time, to see if he was fine. He was.

They were all shocked to learn a helicopter had just crashed yards away from their home.

“It’s not common for helicopters to be flying in this area,” Koehane said. “Me or my husband or our children have noticed before.”

Koehane and her husband got home about an hour after the crash. She said they were escorted by law enforcement to their house.

She couldn’t see the helicopter driving by, but she could see around what area it had crashed.

“I’m assuming it crashed on top of the mountain, on top of the hill, so we couldn’t see any debris or anything like that, but you could see where they had it roped and taped off,” Koehane said.

She said the area where the helicopter crashed was heavily wooded with two mountain ranges on either side.

The next thing she noticed on the way home was how those mountain tops were not visible.

“It’s just even more strange, you know, because there’s a huge mountain range on the other end of this road and you couldn’t see it that day, it was so overcast and rainy,” Koehane said.

Challenges of flying Smokies

Pilots with Scenic Helicopter Tours are used to flying near mountain ranges. They fly almost daily around the Great Smoky Mountains National Park, although not usually near the Cosby area.

Rusty Henderson, chief Pilot with Scenic Helicopter Tours, said the distance between the chopper and the mountains is something they need to pay attention to.

“As that terrain becomes higher and higher that means that we’ll, in turn, have to fly higher and higher; so, being able to safely do so while maintaining a good visual line of sight to what’s going on outside around us,” Henderson said.

Cloudy and foggy weather can hinder the line of sight, he said.

That’s why his crews are constantly checking the weather before taking off, paying attention to the weather as they fly and cancel any flights if they feel the conditions aren’t safe.

So, visibility and cloud coverage are two important conditions pilots need to check before taking off.

“If we’re operating in an area like this, around mountainous terrain, that terrain will get higher and higher elevation, but the cloud level will stay the same, meaning that the space between the ground and those clouds will get smaller and smaller, which does increase the risk,” Henderson said.

It’s unclear if weather played a role in the helicopter crash on Wednesday, but Henderson said that is something the National Transportation Safety Board will look into.

Henderson said he’s personally never been through an NTSB investigation, but he has read past cases so he knows just how lengthy the process can be.

He said the NTSB is very thorough.

“They’ll interview people, people that knew the pilot, people that worked on the helicopter, performed maintenance, sold the helicopter,” Henderson said. “They’ll reach out and branch out as far as they can to get as much information,”

He said whatever comes out of the final report, they will read the findings and adjust their operations at Scenic Helicopter Tours if need be.

In the meantime, both he and Koehane are grateful the crash wasn’t worse than it could have been and they are praying for the families involved.