What happened
During a nighttime flight traveling from Semipalatinsk toward the Semipalatinsk-21 nuclear test site, the flight crew encountered deteriorating weather conditions characterized by significant snowfall and reduced visibility. Due to these below-minimum conditions, the pilot initially intended to divert the flight to Chagan.
However, an individual serving as the commander of the test site, who was a passenger on the flight, requested that the aircraft proceed to the original destination at Semipalatinsk-21. The crew proceeded with the landing sequence, but during the final approach, the aircraft entered a period of zero visibility caused by a sudden snow flurry. This resulted in the aircraft striking the ground near the runway. The impact caused the airframe to separate into two distinct sections and ignited a post-crash fire.
Of the nine people on board, there were 7 fatalities and 2 serious injuries.