On January 28, 2019, about 1750 Pacific standard time, an experimental, amateur-built Whittman Tailwind 8-Wairplane, N12037, was substantially damaged when it was involved in an accident near Prospect, Oregon. The pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The airport caretaker reported that the pilot arrived at the airport three days before the accident with the airplane on a trailer. The pilot assembled the wings on the fuselage and worked on the engine in the days leading up to the accident. On the evening of the accident, the airport caretaker watched the pilot start the engine and taxi the airplane onto runway 20 at Prospect Airport (64S). This was at 1745 and it was nearly dark, as sunset had occurred at 1720. The caretaker observed the pilot add power, accelerate, and depart from runway 20, during which he collided with a runway light. He did not see the direction in which the pilot departed after becoming airborne. When the airplane had not returned after about 20 minutes, the caretaker’s assistant inspected the runway to see if the airplane was on airport property, which it was not. However, the assistant did report that the pilot’s truck was on the ramp and running, with one door open. The assistant further reported that tools were scattered over the ramp’s surface. With this information, the caretaker stated that he called 911 to report that he suspected the pilot was overdue. A search was initiated, and the pilot and the wreckage were located the following morning in dense brush and trees about 1.8 nautical miles southwest of the departure end of runway 20. The wings and fuselage were substantially damaged. The pilot reported to the caretaker that he thought the magnetos had failed. Both magnetos were removed and tested under the supervision of a Federal Aviation Administration inspector. Both magnetos functioned properly, and no anomalies were noted. According to the wreckage recovery company, the fuel tank was examined prior to moving the wreckage. The tank was found undamaged, and it contained no fuel. They noted that there was no smell of fuel or visible signs of pooling fuel at the scene. Multiple attempts by the NTSB IIC to contact the non-rated pilot to discuss the accident and to secure the airframe and engine logbooks for inspection were unsuccessful. The pilot did not submit the National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Report Form 6120.1 .