On August 22, 2004, about 2040 Alaska daylight time, a Cessna 170B airplane, N8238A, sustained substantial damage when the pilot lost directional control, and the airplane nosed down during the landing roll on the Lake Hood Strip at Anchorage, Alaska. The airplane was being operated by the pilot as a visual flight rules (VFR) personal cross-country flight under Title 14, CFR Part 91 when the accident occurred. The solo private pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed. The flight departed Ninilchik Airport, Ninilchik, Alaska, about 1845. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on August 26, and reiterated in a written statement dated august 31, the pilot said during the landing roll the airplane suddenly exited the runway to the left for no apparent reason. He said once off the runway, the airplane nosed down, and came to a stop. He said the airplane dropped down onto the tailwheel, and he exited the airplane. The pilot said there were no known mechanical anomalies with the airplane prior to the accident, and that the airplane sustained structural damage to the left wing, landing gear attachments, and fuselage. In a written report, prepared by an airport police officer who interviewed the pilot at the accident site on August 22, the officer reported the pilot told him he was unable to use the rudder pedals because his headset cord was wrapped around them.