On March 25, 1994, about 1430 central standard time, a Mooney M20J, N4780H, collided with the ground during a forced landing. The airplane was operated by the pilot under 14 CFR Part 91, and visual flight rules. Visual meteorological conditions prevailed. There were no injuries to the private pilot nor the passenger, and the airplane was substantially damaged. An instrument flight rules flight plan had been filed for the personal flight to Tallahassee, Florida. The flight was originating at the time of the accident. The takeoff from runway 36 was observed by a Flight Service Station specialist, who stated that the takeoff roll was unusually long, using over half of the 4,000 foot long runway, and that the engine did not sound as if full power had been achieved. After becoming airborne, the landing gear remained extended. A right downwind turn was made and the airplane proceeded back to the departure runway, at low level. Prior to reaching the runway, the airplane struck the ground with the left wing, east of the approach end of runway 36, and cartwheeled. An inspector from the Alabama Flight Standards District Office, Birmingham, Alabama, examined the wreckage. He reported that the throttle cable was loose. An entry in the aircraft log and the engine log indicated that an annual and a 100 hour inspection, respectively, had been performed on the previous day.