HISTORY OF FLIGHT On June 2, 2015, about 1040 Pacific daylight time, an Ayres Corporation S2R-T34, N4018Q, departed controlled flight and collided with terrain during a low pass in a field near Blythe, California. Morris Ag Air & Sons, Inc., was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 137. The commercial pilot, the sole occupant, was fatally injured. The airplane was destroyed. The local aerial application flight departed about 1000. Visual meteorological conditions prevailed and a flight plan had not been filed. The pilot was in radio contact with a spotter, who witnessed the accident and was also employed by the operator. He stated that the pilot departed about 0730 and had already sprayed one load of chemical. The pilot then reloaded and sprayed two fields (named P4 and P5) until the hopper was empty. The spotter then drove ahead to the next field to be sprayed, P2, and expected the airplane to reload at the airstrip and then come to spray P2. The pilot made a transmission to the spotter asking what the wind conditions were at the field. The spotter replied by telling him that there was a light wind from the southwest. The spotter further stated that he witnessed the airplane coming from the south and clear the powerlines on the south perimeter of the field. The airplane then pitched in a nose-high attitude consistent with the pilot's normal operation of pushing the chemical toward the spread doors. The airplane continued to climb in a near vertical ascent until reaching about 500 feet above ground level (agl), at which point it transitioned into a nose-low vertical descent and collided into the field. The operator stated that the pilot was likely en route back to the airstrip to reload fertilizer in the hopper when the accident occurred. He would have not been applying in the field area where he crashed. PERSONNEL INFORMATION. A review of Federal Aviation Administration (FAA) airman records revealed that the pilot, age 47, held a commercial pilot and certified flight instructor certificates and airplane ratings for single engine and multiengine land, as well as instrument flight. The pilot was issued a second-class medical certificate on November 18, 2014, with the limitation that he must have glasses for near vision. The pilot's personal flight records were not recovered. On his last application for a medical certificate the pilot reported a total flight time of 5,000 hours of which 300 hours occurred in the 6 months prior to that date. AIRCRAFT INFORMATION The low-wing, tailwheel equipped, fixed-gear airplane, was an Ayres Corporation (Thrush) S2R-T34, serial number T34-021, manufactured in 1980. It was powered by a Pratt and Whitney PT6A-34AG driving a Hartzell HC-B3TN-3D constant-speed propeller. No maintenance records were recovered for the airplane. METEOROLOGICAL INFORMATION The closest weather observation station was located in Blythe, which was located 3 miles west of the accident site. About 10 minutes after the accident, the station reported a clear sky with the surface wind variable at 4 kts. No unusual meteorological phenomena were reported by the station or observed by witnesses to the accident. WRECKAGE AND IMPACT INFORMATION The main wreckage was found at the following approximate global positioning system (GPS) coordinates: 33 degrees 35 minutes 19 seconds north latitude by 114 degrees 39 minutes 59 seconds west longitude. The accident site elevation was about 260 feet mean sea level. The airplane came to rest in an agricultural field and the entire wreckage was located in the immediate vicinity. Situated about three miles west of the airport, the accident site was at the southeast corner field adjacent to an east-west paved road to the south and a north-south dirt road that made up the eastern border of the field. In the 75 ft between the accident site and the paved road was a dirt area where a row of powerlines paralleled the road. Immediately south of the paved road was a 30-foot-wide irrigation canal, which was oriented in an east-west direction and the south bank was bordered with trees. The wings came to rest inverted and remained affixed to the fuselage. The leading edges of both wings were uniformly crushed aft and the skin was folded over itself in an accordianed appearance. A ground scar with the similar shape and dimensions as the leading edges of the wings, was located under the wreckage and oriented parallel to the paved road and powerlines. The crater in the middle of that ground scar was about four feet deep and contained portions of the propeller blades. The empennage was found partially intact and "scorpioned" forward over the wings. The rudder was attached to the vertical stabilizer and intact. The horizontal stabilizer and elevator control surfaces remained attached. All control surfaces were accounted for at the accident site. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed by the County of Riverside Sheriff-Coroner. The autopsy report concluded that the death was the result of injuries sustained in the accident. The FAA Civil Aeromedical Institute (CAMI) in Oklahoma City, Oklahoma, conducted a toxicological examination. The report was negative for cyanide, volatiles (ethanol), carbon monoxide, and drugs. TESTS AND RESEARCH The airplane was equipped with a Satloc M3 DGPS global positioning system (GPS) recording device. The returns were recorded every 2 seconds and spanned from the first hit recorded for the flight at 0954:45 to the hit at 1039:32. A review of the return revealed that the airplane flew over several fields and then at 1039:10 exited the field area and headed north. For the last 20 seconds of the data, the airplane maintained an altitude of about 400-420 ft above ground level (agl) maneuvering about 110 to 120 kts. The accident site was located about 1,350 ft north of the last recorded hit. The wings had been removed during recovery. The control surfaces remained attached to the wings. All separation points were along jagged and angular planes. Rod ends were bent at fracture points. The leading edges were crushed aft. Flight control continuity was established from the cockpit controls to the control surfaces. The propeller blades that remained attached to the hub were bent and twisted. Following the accident, a sample of the fuel from Morris Ag Air's fuel truck was submitted to a laboratory for testing. The analysis of the sample fell within the correct specifications.