Incident Details
An instrument student was practicing standard rate descents and climbs at 500 feet per minute. The flight had descended from 3,000 feet MSL to 1,500 feet MSL with the power set at 2,000 RPM. When the student advanced the throttle to full power for the climb, the engine power did not increase. The flight instructor took the flight controls and applied carburetor heat; however, the power decreased through 1,500 RPM to 1,200 RPM.
A field was selected for a forced landing, but the terrain was rough. The airplane struck the ground and became airborne again. The flight instructor observed a powerline and fence ahead of the airplane. He flew the airplane under the powerline and over the fence. Subsequently, the airplane stalled and impacted the ground.
Weather Conditions
The National Weather Service reported the temperature was 46.4 degrees Fahrenheit with a dew point of 39.2 degrees Fahrenheit and a relative humidity of 61 percent. The icing probability curves indicated the conditions were favorable for serious carburetor icing.