On June 24, 1997, at approximately 1000 central daylight time, a Grumman G-164B (Ag Cat) agricultural airplane, N6740Q, was destroyed following loss of control and impact with a fence/brush shortly after takeoff from a private airstrip near Swifton, Arkansas. The commercial pilot, sole occupant in the airplane, was not injured. The airplane was owned and operated by a private individual under Title 14 CFR Part 137. Visual meteorological conditions prevailed for the aerial application flight which was originating at the time of the accident. No flight plan had been filed for the flight. According to the owner of the airplane, he had been flying the airplane for the last several years to meet the aerial application needs of his family's 2,000 acre farm. The owner reported to the Investigator-In-Charge (IIC) that "because of the heavy workload, he had hired the pilot to help out for a month or so." The owner further reported that he (the owner) had completed an application flight and landed the airplane approximately 30 minutes before the accident. The owner stated to the IIC that the airplane was loaded with fertilizer (Urea) and the pilot aligned the airplane for a departure to the west with a 4 to 5 knot tailwind. The owner further stated that he was standing next to the airplane when the pilot applied power for the takeoff and he believed that "the airplane was making full power." The owner reported that the "takeoff roll appeared normal, but shortly after the airplane became airborne, it settled to the ground" impacting a row of brush. The pilot stated, in his written statements and in his interview with the FAA inspector, that this was the first time "I flew this particular airplane." He assisted in the loading of the hopper with Urea fertilizer (1750 pounds) and the refueling of the aircraft (he reported that the airplane was half full or about 50 gallons of fuel). The pilot further reported that temperature was approximately 85 to 87 degrees, and in another report that the temperature was 90 degrees. He stated that the winds were calm on the east end of the airstrip, but on the west end they were 4 to 5 knots from the east. The pilot reported that "I gave the airplane full power, 37 inches manifold pressure and 2250 rpm," and departed to the west. He stated that after liftoff "the airplane would never develop enough power to fly over about 3 feet above the ground--I was trying to stay in ground effect." The airplane impacted a fence row and trees (approximately 6 feet high). The IIC made several unsuccessful attempts to locate the pilot for an interview. Postaccident engine examination, on June 26, 1997, revealed four engine cylinders with low compression ratios (see attached memorandum). The shop manager, where the readings were taken, reported to the IIC that "the data was collected from a cold engine." He further stated that the engine tear down revealed that six cylinders were damaged beyond repair, the crank shaft was broken, and the main case was damaged beyond repair. The manager reported to the IIC that the engine logbook indicated that there was approximately 830 hours on the engine; the engine TBO time was approximately 1,000 hours. No evidence was found to indicate a preimpact failure or malfunction. The airplane took off with a gross weight estimated at 5,500 pounds (see attached calculations). The manufacturer's recommended gross weight for this airplane is 4,500 pounds. FAA and NTSB records indicated that the pilot had been involved in two previous aerial application accidents in the past 12 days. Both of these accidents involved airplanes having a maximum gross weights 3 times the accident airplane and more than twice the horsepower. The pilot's statement in the NTSB's Pilot/Operator Aircraft Accident Report (6120.1/2) indicated that he had "4,000 hours" in Grumman 164Bs. In an interview with the FAA inspector, the pilot stated that "approximately 95 percent of his Ag Cat time was in the 600 horsepowered airplanes." It could not be determined when the pilot last flew a Grumman 164B with the 450 horsepowered engine.