On August 3, 2013, about 1130 central daylight time, an experimental amateur built Titan Tornado 1 airplane, N70786, was substantially damaged when it impacted trees and terrain after takeoff at Wild Rose Idlewild Airport (W23), Wild Rose, Wisconsin. The private pilot was seriously injured. The airplane 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 operated without a flight plan. The local flight was originating at the time of the accident.According to the Federal Aviation Administration (FAA) inspector who traveled to the scene, several witnesses reported that the pilot was having problems with his engine. The pilot had removed and cleaned the spark plugs and was flying the airplane to see if the problem persisted. Shortly after takeoff the engine lost power. The airplane hit trees and then terrain, resulting in substantial damage to both wings, the empennage, and the fuselage. The FAA inspector reported that one spark plug and lead assembly had separated from its cylinder. Examination of the threads and the orifice on the cylinder revealed no anomalies. He stated that the remaining spark plugs were loose but had not separated from their respective cylinders. An examination of the airframe and remaining systems revealed no anomalies. In a telephone conversation with the pilot, he stated that he had not been having problems with the engine and had not removed or cleaned the spark plugs prior to the accident. He stated that the accident flight was the first flight of the airplane; he had just purchased the airplane and had not operated it or flown it prior to the accident.