On July 7, 2006, at 1045 eastern daylight time, an amateur-built J-3K, N43432, was substantially damaged when it impacted terrain during a forced landing in Charlotte, Vermont. The certificated private pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight that originated at a private airstrip in Charlotte, Vermont. The personal flight was conducted under 14 CFR Part 91. According to the pilot, he performed an examination of the airplane, and conducted "minor" engine and fuel system maintenance prior to the flight. The pilot replaced the fuel filter, and installed a fuel primer bulb in the fuel line, after draining all the fuel from the fuel system through a filter strainer and inspecting it for water and debris. The pilot stated that "some small white particulate debris was noted in the filter screen," and that "this is typical for this aircraft and is believed to be tank sealing epoxy paint." The pilot did not observe any water in the fuel. The pilot then filled the fuel tank with the 2 gallons of drained fuel, plus 3 gallons of new fuel, and started the engine. The pilot ran the engine for about 4 minutes, then shut it down and inspected all of the fuel line connections. The pilot stated that the engine ran well, and that all fuel lines remained connected with no leakage. He started the engine again, and the pilot taxied the airplane. He again shut down the engine, and after a 5 minute delay, started it and performed a run-up check. After noticing no abnormalities, he began the takeoff run. During the takeoff, the engine was producing maximum power and the airplane lifted off "in a normal fashion." A few seconds later "the engine stopped without warning," and without any "sputtering or slow decrease in power." The pilot then executed a forced landing, and the airplane impacted a tree, a fence, and the ground. A postaccident examination of the airplane was conducted by a Federal Aviation Administration (FAA) inspector on July 18, 2006, after the airplane had been moved by the owner to his garage. Examination of the engine and fuel system revealed that fuel was present in all fuel lines, and in the carburetor. The fuel primer bulb, installed in the fuel line leading from the fuel tank to the engine was examined and there was no evidence of leakage. The engine crankshaft was rotated by hand, and valvetrain continuity was noted with unhindered movement. A photographic examination of the engine was conducted by a Rotax Aircraft Engines investigator on September 5, 2006, using digital photographs provided by the pilot. The pilot removed the exhaust manifold, and pictures were taken of both pistons, in various positions inside the cylinder, and of the interior cylinder walls. The investigator stated that the pictures revealed nothing unusual about the pistons or cylinders, and that they appeared to look as normal pistons would for that model engine, and with that amount of total time. No excessive carbon deposits were noted on the pistons or in the cylinders. According to the pilot, the experimental airplane had accumulated 272 hours of total airframe time, at the time of the accident. The airplane was on a conditional maintenance program, and the last inspection was performed on August 12, 2005. The Rotax model 503 UL DCDI engine was manufactured in October, 1994. It had accumulated 272 total hours of operation at the time of the accident. The pilot used Premium automotive gasoline premixed with "Air Cooled Engine" 2-cycle oil, mixed at a 50:1 ratio, as prescribed by the engine manufacturer. The pilot bought and registered the airplane in March 2005, and stated that he often performed preflight and preventive maintenance on the engine and fuel system. According to the pilot, the previous airplane's owner experienced an engine seizure about 225 hours of total time. The previous owner believed that the engine experienced a "hot seize," due to an excessively lean fuel/air mixture. According to maintenance records, a top end overhaul of the engine was conducted at 227 hours, and one piston, the piston rings, and the piston needles were replaced. No other engine-related incidents were reported or documented. According to FAA records, the pilot held a private pilot certificate with a rating for airplane single engine land. At the time of the accident, the pilot reported that he had accumulated 100 hours of total flight experience, and 30 hours of flight experience in the accident airplane make and model. The model 503 Rotax engine owner's manual contained the following warnings: WARNING: This engine, by its design is subject to sudden stoppage. Engine stoppage can result in crash landings, forced landings or no power landings. Such crash landings can lead to serious bodily injury or death. WARNING: This is not a certified aircraft engine. It has not received any safety or durability testing, and conforms to no aircraft standards. It is for use in experimental, uncertificated aircraft and vehicles only in which an engine failure will not compromise safety. The model 503 Rotax engine maintenance manual included an itemized maintenance schedule that listed a "general overhaul of the engine" as planned and necessary maintenance for the model 503 engine. A supplemental note to the overhaul of the engine item read: To be carried out every 5 years or every 300 hours, whichever comes first. A general overhaul had never been conducted on the engine.