On April 19, 2020, about 1500 central daylight time, a Piper PA-18 airplane, N3670P, was substantially damaged when it was involved in an accident near Bowie, Texas. The pilot and pilot-rated-passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he taxied the airplane to the south end of a friend's private field, completed an engine run-up, and "checked all systems," with no anomalies noted. The pilot reported that he began the ground roll on a 300° heading and extended the flaps around 40 mph indicated airspeed (IAS). The airplane lifted off with a normal ascent rate and he retracted the flaps about 50 mph IAS. The pilot reported that "it felt like a gust [of wind] picked our left wing up," so he pushed the control stick to the left, but the airplane did not respond. He moved the control stick back to a neutral position then again to the left, but the airplane still did not respond. The airplane continued to bank right and descend as the pilot attempted to bring the wings level. As the airplane approached the ground the pilot pulled the throttle control to idle, then the airplane struck a metal building frame on the northeast side of the field. The airplane came to rest upright and the two occupants egressed without injury. The responding Federal Aviation Administration (FAA) inspector examined the grass field and determined that the airplane's tire tracks were oriented on a 310° heading. Due to the disposition of the wreckage as the accident site, a complete examination was not possible, so the wreckage was relocated to a secure facility where a flight control system examination was completed. The inspector's examination revealed that all flight control cables were attached to their respective control surfaces except for one impact-related separation. The right aileron control cable was separated and exhibited damage, which was determined to be from the impact sequence. The inspector could not find any mechanical reason for the reported right bank.