What happened
The aircraft experienced an in-flight separation of the fore and aft cyclic control linkage tube. Following this mechanical failure, the pilot initiated an emergency descent procedure. To manage the situation, the pilot utilized collective "S" turns specifically designed to reduce airspeed during the approach.
During the forced landing phase, the pilot made a deliberate decision to collide with trees. This action was taken intentionally to cushion the fall and mitigate the impact forces upon ground contact.
The investigation
Post-accident examination of the aircraft revealed the root cause of the control loss. Investigators found that the cyclic pivot bolt, specifically part number AN-174-15, was missing from the assembly. This absence allowed the linkage tube to disconnect while the aircraft was airborne.