On November 16, 2000, about 1120 eastern standard time, an Aerofab, Inc. Lake Seawolf, N65RF, registered to and operated by the United States Department of Commerce, National Oceanic and Atmospheric Administration, collided with the bank of the lake during takeoff from Lake Buffum, Frostproof, Florida, while on 14 CFR Part 91 public-use flight for instructional purposes. Visual meteorological conditions prevailed at the time and a visual flight rules flight plan was filed. The airplane received substantial damage and the airline transport-rated instructor pilot and airline transport-rated dual student were not injured. The flight originated from MacDill Air Force Base(AFB), Florida, the same day about 0848. The aircraft operator reported that after takeoff from MacDill AFB, the flight proceeded to Lake Hancock, where four takeoffs and landings were performed. The flight then proceeded to Bartow, Florida, where the airplane was refueled. The flight departed Bartow at 1100 and proceeded to Lake Buffum. A landing was performed on Lake Buffum followed by a short back taxi prior to commencing takeoff. The instructor pilot took control of the airplane from the dual student during the takeoff run as the airplane approached the end of the lake. The airplane was flying in ground effect when it crossed the edge of the lake, skid 60 feet up a gradual grass slope and launched approximately 4 feet off the ground. The airplane flew 349 feet at this altitude, clearing two barbed wire fences and crossing under power lines. The airplane clipped the top of a third barbed wire fence. The airplane started to lightly drag its tail traveling for 152 feet in this manner. The airplane got back into the air for 130 feet in time to clear a 56-foot-wide ditch. The instructor pilot, seeing a flat field ahead and realizing the airplane was not going to climb, cut the power and set the airplane down. The airplane skid on its belly for 251 feet. The wave height in the lake was estimated at 10 inches, the wind was out of the southeast at 12 knots, and the takeoff was to the east-southeast. The aircraft operator reported they found no mechanical problems with the aircraft structure, flight controls, engine, or propeller after the accident. The accident was reported to the NTSB by NOAA on the day of the accident and NOAA later reported the damage to the airplane was estimated to be between $50,000 and $90,000. At that time the NTSB investigator believed the airplane had received minor damage and the occurrence was classified as an incident and an investigation was not initiated by NTSB. On September 22, 2003, NOAA forwarded photographs of the damage received by the airplane to NTSB and requested that NTSB investigate the occurrence. After review of the photographs, the NTSB classified the occurrence as an accident and began an investigation.