What happened
On February 4, 2010, an An-24RV, registration RA-47360, was scheduled to operate flight YK-425 from Yakutsk to Olekminsk. The aircraft was operated by Yakutia Airlines and was carrying 34 passengers and a crew of four, consisting of a captain, a co-pilot, a flight engineer, and a flight attendant. The flight was part of a larger scheduled service that was intended to continue from Olekminsk to Irkutsk.
The crew underwent pre-flight medical examinations between 06:10 and 06:30, during which no health concerns were reported, and they were cleared for flight. The captain and flight engineer had completed preliminary training in September 2009, while the co-pilot had completed training on September 29, 2009. Following the standard pre-flight preparation schedule, the crew consulted with the duty meteorologist at 06:38. At 06:46, the captain officially decided to proceed with the flight, as recorded by the airport controller.
The investigation
The investigation reviewed the crew's training records, which were conducted under the supervision of the airline's flight department officials. Documentation regarding the flight's preparation was examined, noting that formal flight documentation was not issued to the crew because the planned flight duration was less than two hours. The investigation also confirmed that the weather conditions at the departure, destination, and alternate airports (Yakutsk) were within acceptable limits for the operation.