Accident Overview
A single-engine aircraft operating a charter service (flight GRA4571) departed from a small airstrip in Bishkek, bound for Bukhara, with two passengers and two pilots on board. Approximately one minute after takeoff, during the initial climb, the engine lost power.
Initial Response
The flight crew informed air traffic control of the situation and received clearance for an immediate return to the departure aerodrome. Shortly thereafter, the engine failed completely, prompting the crew to attempt an emergency landing in an open field near the aerodrome.
Emergency Landing and Impact
During the landing, the aircraft collided with a small drainage ditch. The impact caused the left main landing gear and both left wings to separate from the aircraft before it came to rest. All four occupants escaped with minor injuries. The aircraft was damaged beyond repair.
Investigation Findings
The official investigation determined that the loss of engine power in flight most likely resulted from a reduction in the filing of gasoline due to clogging of fuel filters. The appearance, structure, and nature of the impurities found in the fuel on the aircraft were not characteristic of impurities accumulated in the fuel supply system under normal operating conditions. Investigators were unable to locate the source of the impurities in the aircraft's fuel system.