Introduction
On April 26, 2017, a Cessna A188 agricultural aircraft, registration HK2108, operated by AGILL S.A.S., was involved in an accident near the La Milagrosa airstrip in Maní, Casanare, Colombia. The aircraft was destroyed, and the sole pilot was rescued without injuries.
Flight History
The aircraft was scheduled for aerial spraying operations over a field known as Felipe 90. Earlier that morning, the pilot had conducted normal spraying flights. At approximately 10:05 local time, after takeoff from La Milagrosa, the pilot initiated a left turn. During the turn, the aircraft banked sharply to the left. The pilot attempted to correct by applying right control input but received no response. The aircraft continued turning left uncontrollably until it impacted the ground. No post-impact fire occurred.
Aircraft and Pilot Information
The aircraft was a Cessna A188B (serial number C18803081T) built in 1978, with a total of 5,841.8 flight hours. It was equipped with a Continental IO-520-D engine and a McCauley B2A34C205-C propeller. The engine was found to have been operating normally at impact. The pilot was 37 years old, held a valid PCA license and medical certificate, and had 271 total flight hours, with 35 hours on type. The pilot was up to date with recurrent training and was not fatigued.
Accident Site and Damage
The wreckage was concentrated at coordinates N04°48'03.4" W072°13'43.6". The engine and forward empennage remained attached to the fuselage. The left wing suffered severe structural deformation, including fractures and buckling of the aileron. The right wing was largely intact with general buckling on the leading edge and aileron. The left horizontal stabilizer was deformed; the right stabilizer showed positive deformation and the elevator had separated. The vertical stabilizer was intact with minor skin buckling. The left landing gear was fractured. The cockpit was intact. The propeller was buried approximately 40 cm into the ground. Impact dynamics indicated a low angle, low speed, and a final heading of 100°. Herbicide was spilled over about 35 meters from the impact point.
Investigation Findings
Detailed examination of the wreckage revealed a fractured left aileron cable. The cable had been guided by a pulley that was blocked, causing the cable to bind and ultimately fracture. This prevented the pilot from maintaining directional control. The investigation determined that inadequate maintenance processes by the operator failed to detect the pulley blockage and cable wear.
Probable Cause
The probable cause of the accident was the fracture of the left aileron cable caused by blockage of the guide pulley, which jammed the left aileron and prevented the pilot from maintaining directional control, resulting in collision with terrain. A contributing factor was the operator's deficient maintenance procedures that did not detect the pulley blockage and cable wear.