On September 10, 2004, at 1455 central daylight time, a Cessna 150F, N6544F, collided with power lines and terrain during cruise flight in Ancona, Illinois. The private pilot received serious injuries. The airplane was substantially damaged. The 14 CFR Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The airplane had departed the Marshall County Airport (C75), Lacon, Illinois, at approximately 1435, with an intended destination of the Springfield-Capital Airport (SPI), Springfield, Illinois. The pilot reported that he purchased the airplane in Phillips, Wisconsin, and was flying it to his home in Texas when the accident occurred. The pilot reported that on the day prior to the accident, he departed Phillips, Wisconsin, at 1300, and landed at the Portage Municipal Airport (C47), Portage, Wisconsin, at 1530. He stated he was very tired and had a bad headache, so he spent the night in a hotel sleeping from 1700 until 0800 the following morning. The pilot stated he departed C47, at 0930, on the day of the accident, en route to the Rochelle Municipal Airport (RPJ), Rochelle, Illinois. The pilot stated that he purchased fuel at RPJ, but they did not have a sectional chart that he wanted, so he decided to fly to C75, where he landed about 1200. The pilot reported that he purchased his sectional, checked his glucose level, and was tired so he fell asleep under the airplane wing. He stated that he slept for approximately one hour. The pilot stated he then departed C75 with the intention of following highways 39 and 55 to SPI. He stated he lost consciousness near Ancona, Illinois, prior to contacting the power lines, and regained consciousness after the accident. A mechanic at C75 reported that after the pilot woke from his nap, he started his aircraft and started to taxi when he made a sharp turn and got his airplane wedged up against another airplane. The pilot shut down the airplane. As he was exiting the airplane the step loosened and the pilot fell to the ground. The mechanic stated that he and another person ran to the airplane and the pilot stated that he was alright. The mechanic stated he tightened the step for the pilot who seemed fine. The mechanic stated the pilot got back in the airplane and taxied to runway 18. He stated the pilot turned sharply on the taxiway and taxied through the grass. The mechanic stated the airplane entered the runway and began to taxi down the runway. He stated he thought the pilot was going to back-taxi on the runway and takeoff on runway 36; however, when nearing the intersection of runway 13/31, the pilot added full power and took off. The mechanic stated the airplane was about 2/3 the distance down the runway when it took off. He stated the airplane remained at tree top level until it flew out of sight. Witnesses who were working outside in the area reported seeing the airplane flying low from west to east. The witnesses reported they next saw the power lines above them "whip wildly and arc." They then heard the airplane impact the ground and saw it sliding inverted through the field. The pilot provided his post accident medical records to the National Transportation Safety Board (NTSB) for review. The NTSB Medical Officer reviewed the records and spoke with the pilot's daughter who is a physician. The medical officer's report documents that the pilot was an insulin dependent diabetic and that he had coronary bypass surgery two years prior to the accident. Emergency room records indicate the pilot had a oxygen saturation (from pulse oximetry) of 88 percent. The NTSB Medical Officers report states that discussions with the pilot's daughter revealed, "A specific etiology for the pilot's unusual behavior in the days preceding and on the day of the crash has not been identified." The pilot did not hold a current airman's certificate. On April 24, 1970, the pilot was issued a private pilot certificate based on his Canadian private pilot certificate. The limitations on the certificate stated that it expired on April 30, 1972, and that the holder of the certificate must wear corrective lenses. The last annual inspection on the aircraft and engine was performed on October 1, 2003. The entry in the aircraft logbook for the last annual inspection shows the right exhaust was removed from the airplane, repaired, and reinstalled. Post accident inspection of the wreckage was performed by the NTSB and Cessna Aircraft on October 15, 2004. No pre-impact mechanical failures/malfunctions were identified, which would have resulted in the pilot's loss of consciousness.