On June 15, 2014, about 1200 Pacific daylight time, an amphibious float-equipped Piper PA-18-135 airplane, N949JP, was substantially damaged during the landing roll at a private airstrip near Turner Oregon. The airplane was registered to and operated by the private pilot as a visual flight rules (VFR) personal local flight under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan had been filed. The solo pilot was not injured. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on June 25, the pilot said that during the landing roll, the left amphibious float's main wheel collapsed/retracted. Following the collapse of the wheel the airplane pulled hard to the left, which he was not able to control with right brake and rudder. The airplane departed the runway to the left, the float support structure collapsed, and the right wing struck the ground. The right wing sustained structural damage from the lift strut outboard. Prior to the collapse of the left wheel there were no known mechanical problems with the airplane. A Federal Aviation Administration (FAA) aviation safety inspector examined the airplane at the accident site, and said marks on the runway were consistent with the pilot's claim of the left wheel collapsing, and the keel of the left float dragging on the runway. The inspector provided the IIC with photographs of the runway marks and the damage to the airplane. He was unable to examine the collapsed wheel during the initial examination, due to its position in the wreckage. The pilot did not submitted the NTSB 6120.1 PILOT/OPERATOR AIRCRAFT ACCIDENT/INCIDENT REPORT form, after multiple requests. The pilot has not complied with FAA requests to present the airplane's log books, and his personal flight logbooks for examination. The pilot did not make the airplane available for a postaccident examination.