Associated Press

RALEIGH (AP) — The pilot of a Duke Life Flight helicopter that crashed in northeastern North Carolina in 2017 may have accidentally shut off one of the aircraft’s engines just before the second malfunctioning engine failed, federal investigators said.

An investigation by the National Transportation Safety Board suggested pilot Jeff Burke likely got confused by an array of emergency indicators about a problem with one of the engines, news sources reported Friday. In their final report on the crash, which was released last month, NTSB investigators said damaged roller bearings in the No. 2 engine likely caused the engine to malfunction during flight.

The helicopter was en route to Duke University Hospital in Durham from Sentara Albemarle Medical Center in Elizabeth City on Sept. 8, 2017, when it crashed in a grassy field outside the town of Belvidere on the Gates-Perquimans county line. In addition to Burke, flight nurses Kris Harrison and Crystal Sollinger and patient Mary Bartlett were killed.

Because investigators couldn’t recover any recorded data from the flight, they said they couldn’t know exactly which indicators went off and in what sequence. The report said the battery on a recorder installed on the aircraft may have died. But they said Burke likely misread his instruments and believed he was losing power from the No. 1 engine, prompting him to shut it down.

Also, investigators said the throttle control for the undamaged No. 1 engine was found in the “off” position, while the throttle for the damaged one was still in the “flight” position.

“This evidence indicated that the pilot likely shut down the No. 1 engine and that the helicopter continued to fly for some time with power being provided only by the No. 2 engine,” the NTSB report says.

When the No. 2 engine failed a short time later, the helicopter crashed, the report says. Investigators say they could not determine exactly what caused the No. 2 engine to lose all power.