What happened
On July 14, 2023, a Cessna A188B, registration HK2013, was conducting agricultural spraying operations over a rice crop at Finca La Machaca, near Paratebueno, Cundinamarca. The flight was part of a specialized aerial application mission involving the dispersal of 120 gallons of chemical product.
After completing three successful passes over the field, the pilot initiated a closed-circuit maneuver to prepare for a fourth pass. While executing a 45-degree left turn followed by a 270-degree right turn at an altitude of approximately 100 feet, the aircraft experienced a sudden loss of lift. The pilot attempted to recover by deploying flaps and applying left rudder; however, the aircraft continued to descend with a gentle rightward bank. The aircraft subsequently struck trees and impacted the ground in an inverted position.
The investigation
The investigation conducted by the DIACC examined the aircraft's mechanical condition, the pilot's performance, and the aerodynamic sequence of the accident. Investigators inspected the Continental IO-520-D engine and the McCauley propeller, finding no evidence of mechanical failure or pre-impact malfunctions. The engine was found to have impacted the ground at low RPM.
Regarding the crew, the pilot was found to be technically proficient, with a valid commercial license and up-to . The investigation confirmed that the pilot was fit for duty, with no evidence of fatigue or impairment from psychoactive substances. The aircraft's weight and balance were within limits, and the maintenance records were up to date.
Findings
- The primary cause of the accident was the collision with trees caused by an aerodynamic stall.
- The stall occurred because the pilot exceeded the maximum angle of attack during a low-altitude turning maneuver.
- The aircraft was operating at a very low altitude (approximately 100 feet) during the procedure, which left insufficient margin for recovery.
- The centrifugal force generated during the turn increased the load factor, necessitating higher lift and further increasing the angle of attack toward the critical limit.