Accident Overview
On August 13, 2011, at approximately 1030 central daylight time, an Air Tractor AT-402, registration N10119, collided with power lines and subsequently impacted an open field near Uvalde, Texas. The commercial pilot, the sole occupant, was not injured. The airplane sustained substantial damage to the right wing, vertical stabilizer, and rudder.
The aircraft was registered to and operated by L&W Flying Service under 14 Code of Federal Regulations Part 137 as an aerial application flight. Visual meteorological conditions prevailed, and the flight operated without a flight plan. The local flight had originated from Garner Field (UVA) in Uvalde at approximately 0940.
Sequence of Events
According to the pilot, after spraying a field, the airplane's Global Positioning System (GPS) unit malfunctioned. While troubleshooting the issue, he noticed a momentary drop in engine torque, which then returned to 1200 pounds. Shortly thereafter, engine torque dropped again, prompting the pilot to decide to perform a precautionary landing on a road.
During the final approach to the road, the pilot momentarily looked inside the cockpit. When he looked outside again, he saw a set of power lines crossing the road and was able to avoid them. However, he then encountered a second set of power lines. While maneuvering to avoid these lines, the pilot inadvertently stalled the airplane. The right wing dropped, striking the power lines. The airplane then spun around and impacted the terrain in an inverted attitude.
Postaccident Examination
A postaccident examination of the engine and other airplane systems revealed no anomalies. The reason for the drop in engine torque was not determined.