HISTORY OF FLIGHTOn August 13, 2018, about 0230 mountain daylight time, a Cessna 525 airplane, N526CP, was substantially damaged when it collided with an occupied house in Payson City, Utah. The commercial pilot was fatally injured, and the two people in the house received minor injuries. The airplane was operated as an unauthorized flight. According to information provided by the officials from the Payson City Police Department, the pilot had been arrested for domestic violence the previous afternoon. After bail was posted for the pilot, an officer from the Payton City Police Department escorted the pilot to his house so that he could retrieve some items. The officer reported that the pilot did not talk to his wife but told his son to go sleep elsewhere. The officer added that the pilot told his son to "leave the porch lights on for me." The pilot then left the house. Sometime thereafter, the pilot went to the company's hangar and took the airplane without permission. The pilot then flew the airplane into his residence. WRECKAGE AND IMPACT INFORMATIONThe initial impact point consisted of a transmission wire and the roof of a garage located across the street from the pilot's residence. Tire marks at the scene were oriented toward the pilot's house; the airplane impacted the pilot's house slightly. The wreckage consisted of the entire airplane and an overturned vehicle. Impact marks on the vehicle were consistent with contact by the airplane's right wing. All major airplane components were located at the accident site. Flight control continuity was established from the cockpit controls to the respective flight control surfaces. The landing gear appeared to be in the down position. There were no anomalies with the airplane that would have precluded normal operation. MEDICAL AND PATHOLOGICAL INFORMATIONThe Utah Department of Health, Office of the Medical Examiner, Taylorsville, Utah, conducted an autopsy of the pilot. The pilot's cause of death was blunt force injuries, and the manner of death was suicide. Toxicology testing at the Federal Aviation Administration's (FAA) Forensic Sciences Laboratory detected fluoxetine and norfluoxetine in the pilot's specimens. No ethanol or carbon monoxide were detected. Fluoxetine is a prescription medication used to treat depression, obsessive-compulsive disorder, some eating disorders, and panic attacks. Norfluoxetine is its metabolite. On his most recent medical certificate application, the pilot did not report his use of fluoxetine.