What happened
On 2/3/2009, a KA-32T helicopter, registration HL9413, operated by the Forest Aviation Headquarters, crashed into Yeongam Lake in Jeollanam-do, South Korea. The aircraft was conducting specialized training for forest fire fighting, specifically practicing water collection maneuvers.
The flight crew consisted of one instructor pilot and two student pilots. During the training session, the aircraft was performing pattern flights. As the student pilot in the left seat approached the surface of the lake to collect water, the aircraft's descent rate increased significantly. The helicopter ultimately entered a state of settling with power, causing it to impact the water surface and sink.
The investigation
The ARAIB investigation examined the flight history, aircraft maintenance records, and the cockpit voice recorder. Investigators analyzed the flight parameters during the approach to the lake and reviewed the training management protocols of the Forest Aviation Headquarters. The investigation also looked into the survival factors, including the functionality of the aircraft's emergency equipment and the crew's ability to egress the submerged cockpit.