CEN18FA083

The private pilot departed on a multi-leg cross-country flight in his experimental amateur-built airplane. The calculated total flight duration was about 2 hours 16 minutes. There were no radio communications from the pilot or radar data associated with the airplane, and there were no witnesses to the accident. The wreckage was located the morning after the accident about 2.7 miles south of the last airport of departure. Friends of the pilot reported that he typically kept the airplane fueled to capacity. The airplane held 32 total gallons of fuel and its estimated fuel consumption was about 10 gallons per hour. The fuel system was compromised by impact damage and the fuel on board at the time of the accident could not be determined; however, if he had departed initially with a full fuel tank, he would have had sufficient fuel for the flight. Examination of the airframe and engine did not reveal any evidence of mechanical anomalies. One of the wooden propeller blades was shattered, indicative of some level of rotation at impact, but a power level could not be determined. Autopsy and toxicology of the pilot revealed no evidence of physiological impairment or incapacitation. Given the lack of information about the final moments of the flight, the reason for the impact with terrain could not be determined.

The airplane, a Wittman Tailwind, was constructed of a steel tube fuselage and wooden wing structure covered with fabric. The airplane was built by the pilot and received its special airworthiness certificate from the FAA on September 20, 2017. According to FAA documents, no defects were noted during the initial airworthiness certification/inspection. The airplane was powered by a Lycoming O-320-B1A engine equipped with a wooden propeller. According to the engine manufacturer's operating manual, the engine consumed about 10 gallons of fuel per hour. Friends of the pilot stated that the pilot usually kept his fuel tank topped off. The fuel tank capacity of the airplane was 32 total gallons. On January 23, 2018, about 1530 central standard time, an experimental, amateur-built W-10 Tailwind airplane, N251WT, was substantially damaged when it impacted terrain near Sauk Centre Municipal Airport (D39), Sauk Centre, Minnesota. The pilot sustained fatal injuries. The airplane was privately owned and was operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed throughout the area and no flight plan was filed for the flight, which originated from Cambridge Municipal Airport (CBG), Cambridge, Minnesota, about 1415. According to witness statements, fuel records, and the pilot's cell phone records, the pilot fueled the airplane with about 7 gallons of fuel and departed D39 about 1200. The pilot landed at Princeton Municipal Airport (PNM), Princeton, Minnesota, about 1244 and departed about 1324. The pilot then landed at CBG about 1341 before departing about 1415. After landing at D39 about 1515, the pilot brought the airplane to a full stop on runway 32, taxied back to the end of the runway, and subsequently departed. The approximate total flight time from when the pilot originally departed from D39 at 1200, to the time of the accident, was 2 hours 16 minutes, and the total distance flown was about 155 miles. There were no recorded radio communications from the pilot or radar information associated with the airplane. When the pilot did not return as expected, family members contacted authorities and an ALNOT was issued. The airplane wreckage was located about 0820 the next morning about 2.7 statute miles south of D39. The search was assisted by the Air Force Forensic Cellular Team. The Ramsey County Medical Examiner's Office, St. Paul, Minnesota, performed an autopsy of the pilot. The cause of death was blunt trauma. Toxicology testing performed at the FAA Forensic Sciences Laboratory identified no tested-for drugs, ethanol, or carbon monoxide. The reported weather at D39 about the time of the accident included clear skies, 10 miles visibility, and wind from 350° at 3 knots. The pilot held a private pilot certificate. According to pilot logbook information provided by family members, his total flight experience was about 306 hours. No flight time was logged between July 2012 andSeptember 2017; 24 hours were logged between September 2017 and the accident. The pilot's most recent flight review was completed on September 7, 2017. His first flight in the accident airplane was on October 25, 2017, and he had logged about 18 hours in the airplane before the accident. The pilot did not hold a Federal Aviation Administration (FAA) airman medical certificate but reported that he had completed the requirements for operation under BasicMed on August 28, 2017. The accident site was located in a large plowed field. The left side of the cabin structure had been moved by first responders. There was no evidence of a postcrash fire and there was no odor of fuel at the site. There was no evidence in the surrounding area of impact with any obstructions prior to ground impact. Signatures at the site indicated that the airplane impacted the ground in an approximate 45° nose-down, wings-level attitude. The cockpit and front structure of the cabin were mostly destroyed by impact forces. The leading edges of both wings were destroyed. The empennage was bent slightly forward and crumpled along its longitudinal length. The fuel tank and fuel lines were compromised. One propeller blade was visible and was relatively undamaged. The second propeller blade was found shattered underneath the engine. The right elevator was found separated from the elevator control system and moved freely. The left elevator was in the full down position and could not be moved. The engine crankshaft was rotated by hand and drivetrain continuity was established from the propeller to the gearbox. Thumb compression was established on all cylinders. The spark plugs exhibited normal wear patterns. The left and right magnetos were removed but could not be tested due to impact damage. The oil sump was found broken; the engine exhaust and intake pipes were crushed up and aft. The crankshaft flange was deformed, and the starter ring was broken. The oil cooler was crushed aft. The throttle and mixture cables were broken due to impact damage. The carburetor was impact damaged and could not be tested. The fuel lines were compromised by impact damage. No mechanical anomalies were found during the engine examination. Access panels and fabric were removed to facilitate a detailed flight control examination. Flight control continuity was established from the cockpit to all control surfaces, except the connection to the right elevator control horn. The control horn was found fractured adjacent to a weld joint. The left elevator was connected and appeared undamaged. Examination of the right elevator tubular frame revealed fractures consistent with overstress. Similar overstress fractures were found on the left elevator tubular frame. The overstress fractures were consistent with impact forces. The right elevator skin adjacent to its attachment hinges showed marks consistent with overtravel. The attachment hinges for the left elevator revealed evidence of overtravel in the downwarddirection. The overstress fractures and overtravel marks were consistent with impact forces. No other anomalies were found during the airframe examination.