On September 6, 2002, at 1010 central daylight time, an amateur-built Brooks Sonerai 2L, N356RB, piloted by a commercial pilot, was substantially damaged during a forced landing following a partial loss of engine power immediately after takeoff. The airplane had just departed runway 18 (3,899 feet x 75 feet, asphalt) at the Ingersoll Airport (CTK), Canton, Illinois, with the intention of remaining within the local traffic pattern. Visual meteorological conditions prevailed. The flight was being conducted under 14 CFR Part 91 and was not on a flight plan. The pilot sustained minor injuries. In his written statement, the pilot noted that shortly after takeoff, approximately 100 feet agl, "the engine began to sputter and lose r.p.m.'s." He reported that he was not able to return to the airport due to the reduction in power available. He selected a bean field, and set up for a forced landing. He stated "I apparently stalled the a/c in an almost wings level condition at maybe 25' a.g.l." The aircraft impacted the bean field, "collapsed the gear, bounced in the air and went over on its tail", according to the pilot. The pilot reported that he had installed a new carburetor in the days prior to the accident. "The new carb required that I have an adapter piece fabricated to mate to the existing intake manifold flange - which I did." The pilot goes on to state that he had made two static run-ups with no problems noted. In addition, he reported that he had conducted a full static run-up shortly before takeoff on the accident flight. A post-accident examination revealed that the mounting flanges of the aircraft engine intake manifold and the carburetor mounting flange did not seal completely. In addition, one coil on the electronic ignition was found to be cracked and failed to produce a spark at its associated spark plugs.