What happened
On April 19, 2010, an AS-350 B2 helicopter, registration RA-04106, operated by Barkol Airlines, departed from Bykovo Airport as part of flight assignment No 541. The crew, consisting of an instructor pilot and two trainee pilots, was conducting a training flight intended to practice crew responses to engine failure, in accordance with an approved flight crew retraining program.
The crew completed medical examinations at the Bykovo Airport medical station at 05:20 and were cleared for flight. The weather conditions were within the required minimums and did not prevent the mission. Following a pre-flight inspection by the instructor, which revealed no technical issues, the helicopter took off at 06:50. The initial flight to the training area near Ostrov, Moscow Region, proceeded without deviations, and engine parameters remained within the limits specified in the flight manual.
At 09:45, the helicopter returned to Bykovo Airport to refuel. After completing refueling and necessary procedures, the crew received takeoff clearance from the airport controller at 10:37. The second takeoff occurred at 10:45, with the aircraft's takeoff mass recorded at 1970kg and a center of gravity of 3.30m, both within permissible limits.