On May 1, 2013, about 1240 central daylight time, a Robert Mason Kolb Mark 3X airplane, N125KP, collided with trees and a fence after departing from a private airstrip in Lawrence, Kansas. The non-certificated pilot received serious injuries. The airplane was owned and operated by a private individual; however, the airplane was still registered to the previous owner. The airplane was being operated as a 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed for the local flight and no flight plan was filed. The local flight was originating at the time of the accident. The pilot's wife witnessed the accident. She stated she first saw the airplane on the ground with the engine running; the flight controls moved and the engine revved up and down. The power increased again and the airplane began to move. The tail of the airplane lifted off and the airplane veered slightly in one direction, straightened out, and the power increased. The airplane lifted off the ground and made a slight turn to the right before it impacted the trees and a fence at the southwest corner of their property. The pilot initially stated that the engine lost power on takeoff. The pilot then stated to a Federal Aviation Administration Inspector that he did not remember what happened. A visual examination of the aircraft and engine did not reveal any anomalies that would have prevented normal operation. The fence and trees were about 900 feet from the beginning of the airstrip. The pilot departed to the south on a flat area of runway that was 300 foot long topped with freshly seeded dirt. The weather conditions recorded at the Lawrence Municipal Airport (LWC), Lawrence, Kansas, located 6 miles north of the accident site, at 1252, were: wind from 060 degrees at 10 knots gusting to 14 knots, visibility 8 miles, sky condition 4,000 feet scattered, temperature 26 degrees Celsius, dew point 16 degrees Celsius, and altimeter 29.98 inches of mercury. A review of records revealed that the pilot did not hold a pilot certificate. The pilot stated he purchased the already built airplane a couple of months prior to the accident and had flown it 2 or 3 hours. He stated he has flown for about 40 years and that he had about 40 hours of helicopter flight time. The airplane was issued a Special Experimental Light Sport Airworthiness certificate on October 18, 2006. The airplane was powered by a Rotax 582 reciprocating engine.