On September 11, 2011, about 0930 eastern daylight time, a Mooney M20C, N9266M, experienced a loss of engine power during a climb after takeoff from Kokomo Municipal Airport (OKK), Kokomo, Indiana. The pilot subsequently made an off airport forced landing to a field. Both certificated airline transport pilots sustained minor injuries. The airplane sustained substantial damage to the fuselage. 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 and an instrument rules flight plan had been filed for the flight that was destined for Grissom Air Reserve Base, Peru, Indiana, where the pilot was going to practice approaches. The pilot stated that the airplane experienced a loss of engine power/speed of about 200 rpm while about 400-500 feet above the departure end of runway 14. The airplane stopped accelerating and climbing. The pilot executed a shallow left turn to a corn field and then attempted to regain engine power. The pilot selected the right fuel tank, cycled and then left the carburetor heat on, confirmed that the fuel pump was on, cycled the throttle control two times from idle to fully forward, cycled the mixture control from rich to lean to rich, confirmed the propeller control was fully forward, confirmed that the magnetos were in the both position, and cycled the throttle three more times. Engine power was not regained, and the pilot landed on a corn field with the impact occurring as the stall warning horn annunciated. Examination of the airplane by the Federal Aviation Administration, confirmed engine control continuity. There was no obstruction in either the engine induction or exhaust systems. Fuel samples taken from both wing tanks and the gascolator did not contain contaminant. The fuel selector functioned without any mechanical anomalies. The gascolator screen was not obstructed. The magneto P-lead was connected. The spark plugs did not exhibit any anomalies. The Grissom Air Reserve Base, Peru, Indiana, automated weather observing system recorded a temperature and dew point of 59 degree Fahrenheit. The carburetor icing chart in FAA Special Airworthiness Information Bulletin, CE-09-35, indicates serious icing at cruise power at a temperature and dew point of 59 degree Fahrenheit.