Incident Overview
On March 11, 2023, at 12:20 local time, a C-T206H aircraft with registration HL1113, owned and operated by SEOKWANG AeroSurvey Co., Ltd., suffered an engine failure while cruising over Hoengseong-gun, Gangwon-do, Republic of Korea. The aircraft was engaged in an aerial survey mission. According to the official report, the engine stopped with a distinct "bang" sound. The pilot initiated a glide and successfully performed an emergency landing on a pasture within the Livestock Research Institute in Dunnae-myeon, Hoengseong-gun.
Aircraft Information
The aircraft, a C-T206H (type certificate issued by Cessna), was registered as HL1113. It was equipped with a Lycoming TIO-540-AJ1A engine. The accident location was recorded at coordinates N 37°29′52.59″, E 128°09′41.05″.
Engine Failure Analysis
The ARAIB investigation concentrated on the powerplant, specifically cylinder 6. The examination revealed a cascade of mechanical failures beginning with the connecting rod small end bushing, followed by the connecting rod small end, the connecting rod itself, and ultimately the camshaft. These sequential damages resulted in the complete loss of engine power.
Probable Cause
The ARAIB determined that the probable cause of the accident was "engine stopped by cascade damages to engine cylinder 6’s connecting rod small end bushing, the connecting rod small end, the connecting rod, and camshaft."