What happened
A scheduled passenger service departed from Istanbul-Yeşilköy Airport at 22:45 local time, bound for Antalya. The flight was carrying a total of 154 people, consisting of 146 passengers and eight crew members. While cruising at 25,000 feet past the Afyon VOR, the flight crew requested a descent to 13,000 feet.
At approximately 23:11 local time, the captain observed the lights of Antalya and began an approach toward runway 36. However, the aircraft was actually positioned roughly 100 km north of its intended destination. During the night descent, while operating under Visual Flight Rules (VFR) at an altitude of 3,700 feet, the aircraft type struck the slope of Mt Karakaya, which stands at 1,371 meters, south of Isparta. The impact caused the plane to disintegrate, with wreckage recovered at an elevation of 1,130 meters. There were 154 fatalities.
Findings
The investigation determined that the crew mistakenly identified the lights of Isparta as those of Antalya. This led to a premature descent while the aircraft was still significantly north of its target. The accident was a result of navigational errors where the crew failed to maintain proper visual references, leading to controlled flight into terrain.