Primary finding
Probable cause
The pilot did not maintain sufficient airspeed while maneuvering, which resulted in an aerodynamic stall at a low altitude.
Investigator assessment
Analysis narrative
The accident occurred during an aerial-application flight as the pilot maneuvered around a tower. The pilot reported that he had the tower in sight as he maneuvered toward the field being sprayed, and during that turn, the airplane began to shudder as if entering an aerodynamic stall. The pilot attempted to recover from the aerodynamic stall by reducing the elevator input, but the airplane continued to descend rapidly and collided with a tower guy-wire. The pilot stated that there were no preimpact mechanical malfunctions or failures that would have precluded normal operation of the airplane.
Source record
Factual narrative
On April 9, 2012, at 0930 central daylight time, an Ayres Corporation model S2R-T15 airplane, N64DX, was substantially damaged when it collided with a tower guy-wire during an aerial-application flight near Lakin, Kansas. The pilot sustained serious injuries. The airplane was registered to and operated by Tri Rotor Spray & Chemical, under the provisions of 14 Code of Federal Regulations Part 137 without a flight plan. Day visual meteorological conditions prevailed for the local flight that originated from Lakin Airport (36K), Lakin, Kansas, about 0920. The pilot reported that he had the tower in sight as he maneuvered back toward the field being sprayed. While in the turn, the airplane began to shudder as if entering an aerodynamic stall. The pilot reduced elevator input in an attempt to recover from the aerodynamic stall as he continued the turn to avoid the tower. He stated that the airplane was descending rapidly when the right wing collided with a tower guy-wire. The airplane subsequently collided with the terrain. The pilot reported that there were no preimpact mechanical malfunctions or failures that would have precluded normal operation of the airplane. The closest weather observing station was at the Garden City Regional Airport (KGCK), located about 25 miles east of the accident site. At 0930, the KGCK automated surface observing system reported the following weather conditions: wind 160 degrees at 7 knots; visibility 5 miles with mist; scattered clouds at 800 feet above ground level (agl) and an overcast ceiling at 1,500 feet agl; temperature 13 degrees Celsius; dew point 12 degrees Celsius; altimeter setting 30.14 inches of mercury.