It was piloted by a crew consisting of Captain Ararat L. Dallakyan, co-pilot Alexander Ovanisyan, and flight engineer Zhora Davtyan.

The approach scheme for Stepanakert airport included a maneuver near the OPRS Aghdam, located 20 kilometers to the northwest in the territory of the Azerbaijan SSR.

[1] By that moment, the captain had already started doubting the calculations for determining the aircraft's location, but the ground was obscured by a continuous cloud layer with an upper boundary of 3000-3300 meters.

The dispatcher, checking the aircraft's location by radar, gave permission to descend at the Lachin traverse from the safe altitude to 3900 meters.

In reality, the mountain seen was at an altitude of 3616 meters, so the crew, having incorrectly determined their location, began an early descent (before reaching the traverse).

Since the Kafan airport dispatcher was not controlling the aircraft's flight, the crew, having reached the level of 3900 meters at 10:07, did not report this and continued the descent without delay.

[1] At 10:09:57, the Yak-40 descending in the clouds collided with a mountain of the Karabakh Ridge at an altitude of 2520 meters, 22 kilometers west of Stepanakert airport, and was completely destroyed.