What happened
During the approach phase of flight, the aircraft type entered a series of aggressive maneuvers. A surviving passenger noted that the plane performed a left turn that left the aircraft nearly inverted. After briefly leveling the wings, the plane entered a second left turn of similar intensity. This was followed by a steep dive that resulted in the aircraft striking a building.
While the engines appeared to be operating normally during the sequence, the pilot was performing sharp turns throughout the descent. Radar tracking showed the aircraft was traveling at an average speed of 120 knots along the approach course. At the time of the accident, the weather conditions consisted of mist with a visibility of 3 miles and a broken cloud ceiling at 1,100 feet.
Findings
Investigations into the aircraft and engines found no mechanical failures or anomalies prior to the impact. However, data from the pilot's handbook indicated that at a 60-degree bank angle with approach flaps, the stall speed is approximately 123 knots, which is higher than the recorded approach speed of 120 knots. This suggests that the steep turns may have induced an aerodynamic stall.
Toxicology results for the pilot showed the presence of imipramine, carbamazepine, and morphine in the blood and urine. The pilot had a documented history of a neurological disorder and had recently been treated for viral meningitis and skin infections. The pilot was taking imipramine, an antidepressant known to impair cognitive functions, and carbamazepine, which can affect psychomotor performance. While morphine was detected, there was no recent prescription for opiates found in the medical records. Notably, the pilot's underlying medical conditions and regular medications were not disclosed on his application for an airman medical certificate.