On April 21, 2017, about 1300 central daylight time, an Air Tractor AT602 agricultural airplane, N653LA, conducted a forced landing near Vidrine, Louisiana. The pilot was not injured and the airplane was substantially damaged during the landing. The airplane was registered to and operated by Central Farmers Cooperative dba Central Farmers Flying Service under the provisions of 14 Code of Federal Regulations Part 137 as an aerial application flight. Visual meteorological conditions prevailed at the time. The pilot reported that he was conducting spray operations, adding that during turns, the fuel pressure would vary from 19 to 20 psi. Even though he hadn't seen the variance before, he thought the it appeared normal. Then during a turn, the engine lost power. He turned on the [fuel] boost pump, and engine ignitor, but the engine did not restart. The pilot then conducted a forced landing in a rice field. During the landing, the airplane impacted several levees. The airplane's main landing gear were torn off during the landing, and the airplane came to a stop on its belly. The pilot then looked in the fuel tanks and reported that fuel was visible in both left and right fuel tanks. Two other people who were assisting the pilot, who arrived on scene, reported there was 3 to 4 inches of fuel in each tank, and fuel was leaking from the tanks. The responding Federal Aviation Administration (FAA) inspector noted substantial damage to the airplane's left and right wings. He added that the fuel tanks were empty when he arrived, but it appeared that both tanks had been breached and leaked their contents on the ground. The airplane was partially dismantled, including removal of the wings, for recovery and then transported to a repair facility. An examination was then conducted by the NTSB Investigator-in-Charge and a technical representative from the airframe manufacturer. The engine fuel lines, including the Py line, were checked and there were no apparent damage or leaks in the lines. The airframe fuel filter, located on the firewall, was opened; the filter/canister was full of fuel. The engine high pressure fuel pump filter bowl was opened, and the fuel level was about one inch below the top; no debris or contaminates were found. Approximately 1 quart of fuel was drained from the airplane's fuel header tank; the fuel appeared clean. Without electrical power, (and the wings removed from the airplane) the left and right fuel gauges read about 1/16 inch and 1/8 inch above empty, respectively. Electrical power was applied to the airplane, and a self-test was successful on the Shadin fuel flowmeter. The unit displayed 52.1 for fuel remaining, and 157 for fuel used. The airplane was equipped with a 210-gallon fuel system. The flowmeter does not have a fuel level sensing capability, but subtracts fuel from what the user (pilot) input into the meter. The flowmeter was programed to 209, at the last refueling or instrument reset. The engine was separated from the airframe and sent to overhaul/repair facility. Prior to overhaul, the engine was placed in an engine test cell. Under the supervision of an FAA inspector, an engine test run was conducted. The engine started and ran, with no abnormalities noted. A reason for the loss of engine power was not found.