AFTER TAKING OFF AND CLIMBING ABOUT 250-300 FEET, THE ENGINE LOST POWER AND 'THE PROP QUIT ROTATING.' THE PILOT ATTEMPTED TO MAKE A FORCED LANDING IN A FIELD ADJACENT TO THE RUNWAY BUT IN THE PROCESS, THE RIGHT WING CONTACTED THE GROUND AND THE AIRPLANE CARTWHEELED. PARTIAL DISASSEMBLY OF THE ENGINE FAILED TO DISCLOSE WHY THE ENGINE LOST POWER.