The pilot involved in a fatal May 27 plane crash near Haines shut off one of the engines during the flight and couldn’t restart it, according to the lone survivor.

In an interview with crash survivor Chan Valentine, a National Transportation Safety Board investigator learned that about 20 minutes into the flight from Juneau to Haines, “the pilot intentionally shut down the right engine and was demonstrating how to restart the engine during flight,” a NTSB preliminary accident report said.

Pilot David Kunat made several unsuccessful attempts to restart the Piper Comanche’s right engine using electrical power. When that failed, he attempted to “air-start the engine by gaining altitude and diving the airplane down to use airflow to assist in rotating the engine,” the accident report said.

“It’s like pushing a motorcycle and popping the clutch to get it started,” said NTSB Alaska Regional Chief Clint Johnson.

After two failed attempts at air-starting the engine, Kunat decided to try and land on a gravel airstrip at Glacier Point.

“We have been told by the passenger there was a degraded battery that maybe led to the problem, but that’s preliminary information and something the investigative team is looking very closely at,” Johnson said.

Valentine, who suffered multiple broken bones, told the NTSB that Kunat wanted to land at Glacier Point and use a battery booster to start the engine.

“As the airplane approached the airstrip, the pilot made a low-level pass to check the conditions at the airstrip,” the accident reports said. “(Valentine) concluded by stating this was his last memories of the flight.”

Kunat and passenger Stanley Su Quoc Nguyen, also a pilot, were killed in the crash.

A local family and a visitor from Yakutat witnessed the crash, as well as a local tour guide who later came to help, and kept the plane above water as the tide moved in long enough for emergency responders to rescue Valentine.

Steve Dice, a heavy equipment operator from Yakutat, was standing across Lynn Canal about two miles east of Glacier Point as he watched the harrowing scene through binoculars.

“Dice stated the airplane reached the end of the airstrip, descended just before it banked to the right, and subsequently impacted the shoreline in a right wing-down, nose-down attitude,” the report states.

The NTSB investigator found impact damage consistent with Dice’s observations.

“The left propeller blades revealed gouging, twisting and material loss of one blade,” the report states. “The right propeller was found in a feathered position with one blade bent rearward.”

Investigators found that the landing gear was in the down position along with the landing gear switch. The emergency landing gear handle had been removed from its stowed position and was engaged on the “emergency disengage control.”

“With the handle being removed, what we’re thinking is he ended up having to pump the gear down manually,” Johnson said.

It’s possible the landing gear and the flaps, which were up despite the lever being in the down position, weren’t receiving power due to the bad battery and the dead engine.

Regarding the potential bad battery and the engine shutdown, investigators are working with representatives from the plane and engine manufacturers to better understand the plane’s electrical systems.

“There was an electrical issue going on with the airplane,” Johnson said. “They couldn’t get the engine restarted because there was a degraded battery. What we’re figuring out is what is the relationship to those systems with a dead right engine. We don’t quite yet exactly know how those systems work.”

Johnson said they will also learn, based on fuel levels and other performance issues, whether or not Kunat could have safely landed at the Haines airport with a single engine.

“Haines wasn’t that much farther, so hopefully the investigative team will be able to figure that out,” Johnson said.

The NTSB plans to conduct more interviews with Valentine when his health improves.

The wrecked plane is currently in Gustavus and investigators are headed there next week to continue the investigation.

Johnson said the next report will be available within a year.

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