What happened
The aircraft was operating a scheduled service from Okha to Khabarovsk, with planned intermediate stops at Nikolayevsk-on-Amur and Nijnetambovskoye. During the descent phase toward Nijnetambovskoye, the pilot faced marginal weather conditions that limited visibility. To maintain situational awareness in these low-visibility conditions, the crew reduced their altitude to the minimum allowable level for the approach.
While on final approach at an altitude of approximately 50 metres, the right wing structure failed and detached from the fuselage. The sudden loss of lift caused the aircraft to nose down rapidly, resulting in a crash into a nearby pasture. There were no survivors among the 16 occupants aboard the plane.
Findings
The investigation determined that the accident was caused by the structural failure of the right wing during approach. This failure resulted from inadequate repairs previously performed on four supporting beams within the wing structure.
Several contributing factors were identified in the official findings:
- Incorrect calculations regarding the dimensions of shaped couplings and the diameter of rivets used during repair.
- Inaccurate documentation of the repair work in the aircraft logbook.
- The logbook only recorded repairs to spars number 2 and 6, omitting critical work on spars number 4 and 8.
- The aircraft was overloaded by 562 kilos at takeoff from Nikolayevsk-on-Amur, with a total weight of 6,862 kg.