On May 8, 2017, about 1330 Pacific daylight time, a Piper PA18A airplane, N245KW, sustained substantial damage when it impacted terrain shortly after takeoff from Coeur d'Alene Airport (COE), Coeur d'Alene, Idaho. The private pilot sustained minor injuries. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan had been filed for the local flight. The purpose of the flight was to practice maneuvers in the local area. The pilot, who was seated in the front seat, reported that during takeoff he applied one notch of flaps to assist with a shorter takeoff roll. During the initial climb, the airplane yawed to the left and he applied the right rudder; however, the airplane did not respond. About 50 to 75 ft above ground level, the pilot retarded the throttle, and initiated a forced landing. The airplane impacted the ground in a nose down attitude and came to rest oriented about 90° perpendicular to the runway. On July 20, 2017, the airplane was examined at a secure facility by an NTSB Investigator accompanied by a Federal Aviation Administration Inspector. The right rudder pedal was found full forward against the firewall and trapped behind the cabin's front "V" brace. The right rudder cable, between the front and rear seat, had detached at the rear seat foot pedal connection. The thimble remained attached to the rear seat pedal assembly, and the free end of the cable was found loosely threaded through its swage sleeve. The failed rudder cable and swage sleeve appeared bright and clean when compared to the remaining rudder cables in the system, consistent with its recent replacement. There was no annotation in the maintenance logbooks indicating the cable had been replaced. Right rudder cable from rudder intact. Cable thimble to front seat attached, cable missing