On November 24, 1997, at 1600 central standard time, a Gulfstream-Schweizer G-164B agricultural airplane (which was modified as a 2 seat trainer), owned and operated by Barham Bros. Inc., of Oak, Louisiana, was substantially damaged, during a forced landing following a loss of control after takeoff, near Lecompte, Louisiana. The instructor pilot sustained minor injuries and the student pilot received serious injuries. Visual meteorological conditions prevailed for the Title 14 CFR Part 91 instructional flight, for which no flight plan was filed. The flight originated from a grass airstrip at Summerville Airport, Lecompte, Louisiana, at 1559. In an interview the instructor pilot reported to the Safety Board that, the flight was intended for instruction in aerial application. He was seated in the front seat, and the student was seated in the rear seat. With the student pilot at the controls, they executed a normal take off from runway 11. During the initial climb, at about 50 to 75 feet AGL, the instructor noticed that the airspeed was decaying, and recalled telling the student several times to push forward on the controls. As the aircraft began to descend, the instructor took control of the airplane and attempted to push forward on the controls, but the controls would not move forward. During this aforementioned sequence, the instructor reported that he recalls a towel that was in the front seat with him, seem to "hang in the air", relating to some negative "G" forces. Subsequently, the airplane crossed over a power line, impacted a pecan tree, and came to rest on the right wing, in the upright position. Examination of the aircraft by an FAA airworthiness inspector revealed that structural damaged was sustained by both wings and the fuselage. The propeller was found curled and the right main gear separated from the airplane. During the wreckage examination, the inspector checked flight control continuity from the cockpit controls to the elevator, ailerons, and rudder control surfaces. All flight controls responded and moved the flight control surfaces through their respective full operating ranges. After the control system continuity check, the inspector found a battery cover laying free beside the elevator control push tube. He reported that there were several rub marks on the end of the push tube at the "thru" bolt end. Also, he found that the battery cover had two small indentations on it and that the battery was new. No attachment bolts that would be needed to secure the cover to the battery were found. An annual inspection had just been completed on the aircraft on November 20, 1997. Total time since the annual inspection was 5 hours. As of the date of this report, it has not been determined whether the battery was replaced during, before, or after the annual inspection. Numerous attempts (including certified mail) to retrieve a completed NTSB Form 6120.1/2, Pilot/Operator Report, have not been successful. Information in this report was derived from initial interviews and FAA records.