On October 29, 2011, about 1646 eastern daylight time, an experimental amateur-built Brochetti Pietenpol Aircamper, N486LB, impacted trees and terrain following a loss of engine power on takeoff. The airplane was departing from the Smith-Stewart Field Airport (79OH), Vienna, Ohio. The pilot received serious injuries. The airplane sustained substantial damage to it's wings and fuselage. The aircraft was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which was not on a flight plan. The flight was originating at the time of the accident and the intended destination was the Warren Airport (62D), Warren, Ohio. The pilot reported that the airplane had not been flown in the previous three to four weeks and that it had rained on the morning of the accident flight. He stated that he performed a preflight inspection of the airplane and found no anomalies. During the preflight inspection fuel was drained from each of the fuel tanks but was not collected for visual inspection. The pilot stated that the engine start and taxi were normal. He reported that the airplane lifted off during takeoff as expected but then would not climb as expected. The airplane subsequently impacted trees at the end of the runway. At 1651, the recorded temperature and dew point at the Youngstown-Warren Regional Airport, about 4 miles north of the accident site, were 5 degrees Celsius, and 0 degrees Celsius, respectively. According to Federal Aviation Administration (FAA) Special Airworthiness Information Bulletin (SAIB) CE-09-35, the temperature and dew point were in the range for serious carburetor icing potential. In his report, the pilot surmised that carburetor icing or contaminated fuel may have contributed to the loss of engine power. Postaccident examination of the airplane by FAA inspectors revealed that one of the engine's spark plug wire terminals was not attached to its respective spark plug. No other evidence of mechanical malfunctions or failures that would have precluded normal operation were found.