On July 20, 2017, about 1945 eastern daylight time, an Aeronca 11BC airplane; N3154E, was substantially damaged when it was involved in an accident in Gilbert, South Carolina. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that, after making a normal landing, the airplane lurched hard to the left and exited the left side of the runway into the grass area adjacent to the runway and impacted the windsock pole. The airplane ground looped to the left and the right main landing gear collapsed. The airplane came to rest, and the pilot egressed. Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed substantial damage. The left wing was impact damaged, with visible crushing extending aft past the wing strut attach point on the forward spar. The right main landing gear had separated from its mounting location and the right wingtip was damaged. The propeller tips were damaged, and the fuselage beneath the cockpit aft of the firewall was damaged. External examination of the main landing gear and brake assemblies revealed no abnormalities. The airplane was equipped with heel brake pedals at the left cockpit seat; no brake pedals were installed at the right seat location. The left brake pedal was connected to the left wheel brake drum by a cable. Left cable continuity was confirmed, and the cable remained taut. When the heel pedal was actuated manually, it moved forward and aft; normal spring tension was noted. The left wheel and tire were spun manually; the left heel brake was pressed, and the wheel stopped immediately. When the heel brake pressure was released, the wheel became free and spun without restriction or binding. No evidence of a locked brake condition was observed. The right brake pedal cable was separated at the right brake drum due to impact forces (separation of the right main landing gear). Other than the separated cable, the remaining hardware was in place and operated in a normal manner. The left and right brake drums were disassembled. The linings of both brake drums were smooth and no anomalies were noted. All brake shoes were in good condition with minimal wear. All brake shoe springs were in place and tight. All wheel bearings were undamaged with minimal wear. Both main landing gear tires were undamaged and tread wear was minimal. No flat or scuffed spots were noted on either main landing gear tire. According to the maintenance records, the airplane’s most recent annual inspection was completed on June 24, 2017, about 1 month before the accident, and no anomalies were noted with the wheel brakes. The 1956 recorded weather at Columbia Metro Airport (CAE) Columbia, South Carolina, located 12 nautical miles east of the accident site, included wind from 200° at 4 knots; equivalent to a 4-knot right crosswind component and a 1-knot tailwind component.