HISTORY OF FLIGHT On June 1, 2008, at 1203 eastern daylight time, a Cessna 172H, N3910R, was substantially damaged during a forced landing in Brockport, New York. The certificated flight instructor and student pilot were seriously injured. Visual meteorological conditions prevailed and no flight plan was filed for the instructional flight conducted under 14 Code of Federal Regulations Part 91. According to the student pilot, he performed a preflight inspection prior to takeoff and observed 6 gallons in each of the two fuel tanks. After departure, the pilots flew to Genesee County Airport (GVQ), Batavia, New York, where they practiced touch-and-go landings. During the return flight to Ledgedale Airpark (7G0), Brockport, New York, the engine started to "shake" and then "lost power," when the airplane was at an altitude of 1,600 feet. The flight instructor performed a forced landing to a field, during which the airplane impacted trees, and came to rest 150 feet from the tree line. The flight instructor had no memory of the accident; however, he did remember checking the fuel gauges in flight and noting they read 1/4 tank (5 gallons) each side. PERSONNEL INFORMATION The certificated flight instructor held ratings for airplane single-engine land and instrument airplane. He also held an airline transport pilot certificate and commercial pilot certificate. His most recent FAA first-class medical certificate was issued on March 19, 2008. At that time he reported 17,320 hours of total flight experience. Examination of the pilot's logbook revealed it was labeled "single engine time," and contained entries from March 29, 2008 to May 30, 2008. During that time period, the pilot logged 48 hours of flight time, all of which was accumulated in make and model of the accident airplane. The student pilot held an FAA second-class medical certificate, issued on April 1, 2008. At that time, he reported 14 hours of total flight experience. AIRCRAFT INFORMATION The aircraft was owned by the flight instructor and powered by a Continental O-300 engine. According to the airplane and engine logbooks, the most recent annual inspection was completed on July 10, 2007, with no anomalies noted. The tach time at the annual inspection was 7,300 hours and the tach time at the accident was 7,557 hours. The aircraft had a fuel capacity of 38 gallons of useable fuel, and 1 gallon of unusable fuel. METEOROLOGICAL INFORMATION The weather reported at Rochester International Airport (ROC), Rochester, New York, about 11 miles to the east, at 1154, included wind from 280 degrees at 13 knots, gusting to 19 knots, 10 miles visibility, a broken cloud layer at 3,800 feet, an overcast cloud layer at 4,600 feet, temperature 17 degrees Celsius (C), dew point 8 degrees C, and altimeter setting 29.79 inches mercury. WRECKAGE AND IMPACT INFORMATION Examination of the airplane by a representative of the airplane manufacturer and the FAA inspector revealed approximately 1 gallon of fuel was observed in the right tank and 1 quart of fuel was observed in the left tank. The fuel tanks were not compromised and there was no indication of a fuel leak in the fuel system. No fuel was observed in the fuel line from the fuel tank to the fuel strainer. The fuel selector was set to the 'both' position. The throttle knob was full forward, the carburetor heat was in the off position, and the mixture was in the 'rich' position. The flaps were in the retracted position. The engine crankshaft was rotated at the propeller flange and valve train continuity and compression were obtained on all cylinders. ADDITIONAL INFORMATION According to the pilot who flew the airplane prior to the accident flight, he departed for his flight with 18 gallons of fuel, and flew for 1.7 hours. The pilot reported no mechanical anomalies with the airplane during his flight. The airplane was not refueled prior to the accident flight, which was 1.1 hours in duration, according to the aircraft flight log. Fuel consumption calculations performed by a representative of the manufacturer revealed the accident flight would have consumed 8.4 gallons of fuel. The previous flight (1.7 hours in duration) would have consumed 11.5 gallons.