On October 20, 1995, about 1955 central daylight time, a Cessna 182R, registered to the Civil Air Patrol, Inc., crashed into trees about 3.6 nautical miles south-southwest of the Redstone Army Air Field, Redstone Arsenal, Alabama. Visual meteorological conditions prevailed at the time and a VFR flight plan was filed for the 14 CFR Part 91 maintenance test flight. The airplane was substantially damaged and the private- rated pilot and pilot-rated passenger were not injured. The flight originated about 1725, from the Redstone Army Air Field, Redstone Arsenal, Alabama. The pilot stated that three separate flights lasting a total of about 5 hours were scheduled following installation of a rebuilt engine. He performed fuel consumption calculations for these flights. The airplane departed with nearly full fuel tanks for the first flight. The first and second flights were uneventful and both lasted 3.4 hours according to a Hobbs meter. Fueling was not accomplished before the second or accident flight departed. Before departure for the accident flight the pilot stated that he used a commercially fabricated dipstick and determined that the left and right fuel tanks contained 27 and 26 gallons respectively. Examination of the dipstick revealed that the highest graduation in "gallons usable" is "39." The manufacturer of the dipstick indicated that it is to be used only for Cessna 182 model airplanes with "long range" fuel tanks installed. According to the pilot's operating handbook, the total usable quantity of each fuel tank is 44 gallons. After departure on the accident flight, the pilot activated his VFR flight plan then updated his ETA to 1950. The flight returned and he performed two full stop landings. The flight again departed and remained in the traffic pattern for the final full stop landing. During the downwind leg the pilot observed that the fuel gauges indicated near the red line and after turning base, the engine "stopped." He turned toward the airport but landed short in the tops of trees. The airplane descended and came to rest upright left wing low. Both occupants were rescued about 0400 the following morning. The pilot further stated that he did not take into account the additional three takeoff's during fuel consumption calculations. Examination of the airplane by an FAA airworthiness inspector at the crash site revealed no evidence of fuel leakage. The left and right fuel tanks were drained and found to contain less than 1 quart and no fuel respectively. The airplane had been operated according to the tachometer for about 6.0 hours since the fuel tanks were filled. At about 2025, 35 minutes beyond the updated ETA, personnel from the Anniston Automated Flight Service Station (AFSS) contacted the Huntsville Air Traffic Control Tower (HSV ATCT) and asked if they had communicated within the last 30-40 minutes with the accident airplane. At 2027, personnel with the HSV ATCT advised personnel from the Anniston AFSS that the accident airplane was on the ground at "redstone." At 2248, personnel from the Anniston AFSS contacted the HSV ATCT to report an Emergency Locator Transmitter (ELT) being heard by the Air Force Rescue Coordination Center (AFRCC). The ELT signal was reported to be near the Redstone Arsenal. The ELT signal was not heard on the main receiver but on the backup receiver. Search and Rescue operations were started about 2330.