What happened
On October 31, 2019, an EC225LP helicopter, registration HL9619, operated by the National 119 Rescue Headquarters, crashed into the sea near Dokdo. The flight had originated from Daegu, refueed at Ulleungdo, and proceeded to the Dokdo helipad to transport a patient and a caregiver.
During the initial approach to the Dokdo helipad, the pilot experienced significant visual illusions regarding altitude and slope, leading to a go-around. Following the boarding of the passengers, the aircraft departed the helipad. As the helicopter transitioned from the illuminated helipad toward the dark sea, the pilot lost situational awareness. While attempting to increase speed, the pilot misidentified the aircraft's descending attitude as an ascent. This led to continuous forward cyclic inputs, causing the aircraft to descend rapidly into the water only 14 seconds after takeoff. The impact was severe, with an acceleration of at least 54.54 G, resulting in the deaths of all 7 persons on board, including five crew members.
The investigation
The ARAIB examined the wreckage, engine components, and the main gearbox, finding no mechanical defects in the airframe or engines. Analysis of the Cockpit Voice and Flight Data Recorder (CVFDR) revealed that the pilot had commanded the co-pilot to engage Altitude Acquisition (ALT.A) mode, but the Altitude Hold (ALT) mode was actually engaged.
The investigation also looked into the operational environment, noting that the Dokdo helipad lacked adequate entry/exit procedures and had malfunctioning lighting systems. Furthermore, the investigators reviewed the crew's training and fatigue levels, noting that the pilot had reported fatigue on three separate occasions and that the crew had no prior experience conducting night operations at this specific location.