On August 25, 1999, about 1026 central daylight time, a Piper PA-28-140, N6685J, owned by an individual, collided with trees after taking off from the Jackson Airport, Jackson, Alabama. Visual meteorological conditions prevailed at the time, and no flight plan was filed for the 14 CFR Part 91 personal flight. The airplane was substantially damaged. The private-rated pilot and commercial-rated pilot/passenger reported no injuries. Two other passengers reported minor injuries. The flight was originating at the time, and was en route to Baton Rouge, Louisiana. According to the pilot's statement, "...calculating the distance, time, and fuel consumption, I decided 18 gallons of fuel would be needed. Thinking I had 20 gallons of fuel I calculated the weight...120 pounds [fuel]...200 pounds [pilot]...160 pounds [male passenger]...170 pounds [male passenger]...190 pounds [male passenger]...total gross weight for the airplane was 864.50 pounds...did a complete pre-flight check of the airplane...found the airplane had twenty-three to twenty-five gallons of fuel...recalculating the weight in my head I decided that it was 860 pounds, 5.5 pound over weight limit. Thinking back, only three weeks before I had taken off with the same amount of weight...I did a complete check off on everything in the cockpit, and a static run-up only produced 2400 RPM's instead of 2500 RPM's the engine usually produced. After holding the airplane in the static run-up...I released the toe brakes and down the runway we went. Rotating the airplane at 80 MPH, it climbed to about 100 to 150 feet and entered some turbulence, at this time it felt like something was pushing the airplane to the ground...I decided the airplane was not going to climb over the trees and [I] started turning off the fuel selector switch, the master switch, and we went into the trees." According to the FAA inspector's statement, "...aircraft at max gross weight, took off and at approximate 250 feet, aircraft encountered a down draft, stall warning light came on, pilot lowered nose to prevent stall. Aircraft was unable to maintain altitude and hit trees at end of runway." The reported temperature in the area about the time of the accident was about 90 degrees F. The winds were variable at 4 knots. The calculated density altitude was 2332 feet.