The pilot was performing a pre-buy flight in the amateur-built airplane. The takeoff roll was normal until the airplane accelerated between 25 to 50 mph, when the airplane required right rudder to maintain straight flight. After liftoff, without pilot input, the airplane veered left of the runway. The pilot applied right rudder and was able to get the airplane back over the runway. However, he lost control of the airplane as it turned to the left despite the application of full right rudder. The airplane continued to the left until it impacted terrain. The pilot reported having completed a preflight inspection and high-speed taxi prior to the flight, and he did not note any problems. He reported that after the taxi, the owner placed a flight manual into the airplane that he thought may have jammed the rudder. Postaccident examination did not locate a flight manual in the wreckage or surrounding area, and the owner stated that a firefighter had retrieved the manual but didn’t know where in the wreckage that the firefighter had retrieved it. The pilot later thought the vertical stabilizer had more play than expected but reported that the owner told him it was normal. A postimpact examination did not reveal any anomalies in the airplane’s aileron and elevator controls, and damage to the vertical stabilizer precluded a thorough inspection of the rudder system. The airplane’s trim tabs were not installed and were not required to be. The owner had only flown the airplane once in July 2025 and reported that the airplane required constant right rudder to maintain straight flight. The owner reported informing the pilot that the airplane required right rudder. The pilot reported that he was not informed that the airplane needed right rudder and that the trim tabs were not installed. According to the kit manufacturer, extra rudder input would be required when climbing the airplane with a high angle attack and high-power setting. The pilot had logged 22 hours in a different Challenger II in September 2024. In an article published by the Experimental Aircraft Association (EAA), Before You Fly: Thoughts on your first flight and the EAA Flight Advisor Program, they advise pilots that the “Statistics show that 20% of all homebuilt accidents happen during the first two flights and are usually caused by pilot error. Those pilot errors are almost always the result of a pilot flying an aircraft for which he or she wasn't qualified or with which he wasn't familiar. The same problem exists during the first flight of any unfamiliar aircraft, whether it is a homebuilt, vintage or ultralight. The first flight in an airplane might as well be a test flight because, for that pilot, it is a test flight.”