What happened
On August 29, 2010, a Cessna 188-B was performing agricultural spraying operations over a banana plantation near La Unión, Esmeraldas. The aircraft was engaged in its second scheduled flight of the afternoon, having previously completed several successful passes earlier that day.
At approximately 22:19 UTC, while executing an east-to-west pass, the aircraft struck the upper shield wire (guard cable) of the National Interconnected System power lines. The impact caused the aircraft to plummet to the ground, where it caught fire and was destroyed. The pilot, a 56-year-old commercial pilot with extensive experience, sustained one fatality due to the impact and subsequent fire.
The investigation
The investigation examined the flight path, the aircraft's condition, and the operational procedures of the company. Investigators performed a test flight using an ultralight aircraft to evaluate the visibility of the power lines. They found that despite the presence of fiberglass markers on the cables, the wires were extremely difficult to distinguish from the air due to low contrast with the surrounding vegetation.
The board also reviewed the pilot's recent activities and the company's maintenance records. While the aircraft's engine and airframe-related inspections were up to date, investigators noted a lack of documentation regarding the service life and traceability of the propeller. Furthermore, it was determined that the pilot had not performed a formal reconnaissance flight of the specific work area prior to starting the mission, relying instead on a provided map and information from a coordinator.
Findings
- The pilot's attention was divided between maintaining aircraft attitude and using the AG-NAV precision equipment to align the spray pass.
- Loss of situational awareness led the pilot to neglect essential safety measures regarding the proximity of the power lines.
- The use of GPS-based precision technology acted as a distraction during the critical phase of entering the spray pass.
- The high speed of the aircraft (approximately 110 mph) left a very narrow margin for error when maneuvering near obstacles.
- Repeated successful crossings of the cables in previous passes likely increased the pilot's confidence to a level that compromised safety.