On May 26, 2005, about 1530 Alaska daylight time, a Piper PA-31-310 airplane, N65MR, sustained substantial damage when it landed with the landing gear retracted at the Manokotak Airport, Manokotak, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country positioning flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by the Missionary Aviation Repair Center, Soldotna, Alaska. The commercial certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. The flight originated at the Dillingham Airport, Dillingham, Alaska, about 1515, and no flight plan was filed, nor was one required. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on May 27, the pilot reported that during the base leg portion of his approach to the airport, he lowered partial flaps, but did not lower the landing gear. As the approach to the airport continued, the pilot said he failed to complete the landing checklist, and landed with the landing gear retracted. The airplane received structural damage to the fuselage, necessitating replacement/repair of several bulkheads, and a large area of belly skin from the nose wheel to the tail.