On September 6, 2005, about 1800 Alaska daylight time, a float-equipped deHavilland DHC-2 airplane, N199BM, sustained substantial damage when it collided with a river bank during an aborted takeoff, about 18 miles south-southwest of Igiugig, 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 Alaska Air Taxi, LLC, Anchorage, Alaska. The airline transport certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. VFR company flight following procedures were in effect, and the flight was en route to Igiugig. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on September 7, the pilot reported that he was departing eastbound, and up-river, on the Alagnak River. He said the airplane was on-step, and he attempted to lift one float out of the water during the takeoff run, but was unsuccessful. He then decided to abort the takeoff by closing the engine throttle. The pilot indicated that the airplane collided with the river bank, the left float assembly was torn off the fuselage, and the airplane received structural damage to the fuselage.