No fatalities

Aircraft Rescued After Collision with Mt Masim Following VFR Flight into IMC (RA-33668)

Mt Masim, RussiaFlight

On October 12, 1998, a PZL-Mielec AN-2 (registration RA-33668) operated by Bashkirian Airlines - Bashkirskie Avialinii was involved in an aviation accident near Mt Masim, Russia in flight. No fatalities were reported. Investigators recorded the probable cause as: Poor flight planning and preparation; crew decision to continue VFR in IMC; deviation from course and flight below minimum altitude over mountains; flight inspector failure to verify preparations; lack of ATC assistance; low visibility due to clouds. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 1 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Source recordUpdated 2026-07-05Data APIEditorial standards

All 16 occupants of an aircraft were rescued, with three passengers injured, after the crew deviated from the departure route and continued VFR into IMC, leading to a collision with trees on Mt Masim.

Accident

An aircraft departed from Sibay Airport carrying 13 passengers and a crew of three, including one inspector. Despite marginal weather conditions, the crew initiated the flight under visual flight rules (VFR). Shortly after takeoff, the crew failed to follow the prescribed departure route and deviated from the published course.

Approximately half an hour into the flight, weather conditions deteriorated, with low clouds forming. After the aircraft entered clouds, the captain decided to return to Sibay, but this decision was made too late. At that point, the aircraft had strayed 45 kilometers to the northeast of its intended route.

While executing a left turn while still in clouds, the crew did not realize that the aircraft's altitude had become too low. At an altitude of 980 meters, the aircraft collided with trees and crashed on the slope of Mount Masim, which has an elevation of 1,040 meters. Despite the impact, all 16 individuals on board were rescued. Among them, three passengers sustained injuries.

Probable Cause

The official investigation identified the following factors as contributing to the accident:

  • Poor flight planning and preparation,
  • The crew's decision to continue the flight under VFR mode in instrument meteorological conditions (IMC),
  • The crew deviated from the initial course and then continued over mountainous terrain below the minimum prescribed altitude,
  • The flight inspector failed to verify that the crew prepared the flight according to published procedures,
  • Lack of air traffic control (ATC) assistance,
  • Lack of visibility due to low clouds.

Frequently asked questions

What happened in the 12 Oct 1998 PZL-Mielec AN-2 accident near Mt Masim, Russia?

All 16 occupants of an aircraft were rescued, with three passengers injured, after the crew deviated from the departure route and continued VFR into IMC, leading to a collision with trees on Mt Masim.

Were there any fatalities in the 12 Oct 1998 PZL-Mielec AN-2 accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 12 Oct 1998 involved a PZL-Mielec AN-2, registration RA-33668, operated by Bashkirian Airlines - Bashkirskie Avialinii, at Mt Masim, Russia.

What was the probable cause of the accident?

Poor flight planning and preparation; crew decision to continue VFR in IMC; deviation from course and flight below minimum altitude over mountains; flight inspector failure to verify preparations; lack of ATC assistance; low visibility due to clouds.