[1][2] The aircraft performed flight Sh-88 from Leninabad through the Anzob pass to Dushanbe, piloted by a crew led by Captain E. M. Lander.

In reality, they were still 37 kilometers away due to a wind speed error and radio compass failures caused by the aircraft's electrification when passing through dusty haze and nearby thunderstorms.

[1] The Yak-40 was 43 kilometers northwest of Pugus, but the approach controller did not determine its location when he allowed a descent to 4,800 meters at the Dushanbe outer marker, indicating a landing on a magnetic course of 86°.

In turn, the descending crew in clouds, due to radio compass failures in severe turbulence and icing conditions, could not determine their location correctly.

The approach controller, with the necessary radio technical means, did not check whether the aircraft had actually passed the outer marker, instead allowing a descent to the circuit altitude of 3,600 meters.

The circuit controller gave them an azimuth of 300°, not paying attention to the significant excess of the 275° limit, and responded to their position request that he could not provide it since the radar was off (due to equipment change), although an ARP-75 direction finder was available.

[1] The Yak-40, in clouds at 2,840 meters, continued turning left to a course of 180° when at 13:44:00, flying on course 208° at a speed of 380 km/h, it crashed into a mountain slope and was completely destroyed.

The cause of the crash was ATC service violations at Dushanbe airport, failing to meet NPP GA-78 requirements in managing the flight and crew errors in determining the aircraft's position while avoiding thunderstorms in mountainous terrain.