Story thread · 7 reports / 5 sources

Engine shutdown caused fatal Army helicopter crash in Feb.: military

koreatimes.co.kr · 5dShare

A sudden engine failure has been identified as the main cause behind the deadly crash of a military helicopter in February that killed two soldiers, Army officials said Thursday. The AH-1S Cobra helicopter of an Army aviation unit crashed during an emergency landing familiarization training in Gapyeong County, about 55 kilometers northeast of Seoul, on Feb. 9, killing the two warrant officers on board. No civilian damage was reported. The military had since been investigating to determine the exact cause of the crash. According to official findings, an internal cylinder in the helicopter engine was slightly misaligned, causing the engine's central drive shaft to wobble as it turned. The wobble caused violent vibrations, and the spinning shaft began whipping around widely like a jumping rope, known as "shaft whirling," the Army said. When the pilot pushed the throttle back up to climb, the spinning power shaft slammed into a second spinning shaft, instantly generating extreme heat that

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