On April 18, 2020, about 1041 Pacific daylight time, a Cessna T206 airplane, N756TH, was destroyed when it was involved in an accident near Auburn, California. The pilot was fatally injured, and the pilot-rated passenger was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The passenger reported that the pilot planned to fly them in another airplane he owned; however, he noted discrepancies during the preflight (oil residue in the engine compartment) and opted to fly the accident airplane instead, which he also owned. The passenger reported that the pilot performed the preflight inspection on the airplane. Although he did not observe the pilot perform the inspection, he observed the pilot perform preflight inspections previously and he believed the pilot “performed thorough checks.” The passenger stated that shortly after takeoff, at an altitude of about 200 to 300 ft above the ground, the engine lost power. The passenger took over the flight controls and performed an emergency landing to a field near the departure airport. During the landing, the airplane impacted terrain and a post-crash fire ensued. Radar data indicated that the airplane departed runway 25 and turned to the left while climbing to about 155 ft above sea level (agl). The airplane then turned 90° to the right and started to descend until radar data was lost about 1,500 ft northwest of the departure end of the runway 25. The entire flight lasted less than one minute. A postaccident examination of the airplane revealed no catastrophic pre-impact mechanical anomalies; however, when the fuel manifold valve was disassembled, corrosion type debris was noted on the internal screen and liquid was observed within the fuel manifold valve cavity. Water finding paste was used to test the liquid and it was positive for water. A friend of the pilot’s flew the accident airplane on March 13, 2020 and March 26, 2020. During the preflight inspection of both flights, he noted substantial amounts of water in the fuel tanks and fuel system. He stated the fuel tank caps were older and known to leak and allow water into the fuel tanks. The pilot’s friend also stated that the pilot had ordered new fuel tank caps, but they were backordered at the time of the accident. He told the pilot not to fly the airplane until the new fuel tank caps were installed. An autopsy was performed on the pilot by the Office of the Sherriff-Coroner, Placer County, Auburn, California. The cause of death was multiple blunt force and thermal injures. The forensic pathologist reported that the pilot had marked abdominal aorta atherosclerosis and 75 to 90 percent calcific stenosis of portions of his left anterior descending coronary, left circumflex, and left main coronary arteries. Toxicology testing was performed on the pilot by the FAA Forensic Sciences Laboratory. The testing detected hydroxychloroquine in the pilot’s heart blood and urine. Hydroxychloroquine is indicated for use in rheumatoid arthritis, lupus, and malaria treatment. Patients are advised that serious cardiac side effects could occur including a fast or irregular heartbeat, lightheadedness, dizziness, or syncope. The non-impairing medication tamsulosin was also detected in the pilot’s heart blood and urine. The pilot reported taking hydroxychloroquine for a new medical diagnosis of inflammatory arthritis, on his most recent FAA third-class medical certificate, issued February 28, 2020.