Shortly after liftoff, passengers and crew observed sparks emanating from above the main front door. The climb procedure was continued. One minute and twenty-five seconds after takeoff, the crew reduced engine power to nominal settings, but engines number 3 and 4 did not respond and remained at full power. The captain decided to return for an emergency landing. The subsequent approach was unstable. The aircraft landed hard, bounced, and became uncontrollable. It veered off the runway and broke into two sections before bursting into flames. All six occupants aboard were injured.
Probable Cause
According to the official investigation, the accident was caused by an electrical short-circuit in the engine control system for engines number 3 and 4, leading to asymmetric thrust. Contributing factors included a lack of crew training and an excessive emotional stress situation experienced by the crew.