Incident Overview
A dual student was conducting several maneuvers with the left engine windmilling. Carburetor heat was not used despite prevailing carburetor icing conditions. After completing a maneuver and returning to cruise flight, the left engine experienced a power loss.
Instructor Intervention
The instructor assumed control of the aircraft and initiated a normal descent toward a nearby airport. During the descent, the left engine was secured. As the aircraft turned from base leg to final approach, the right engine's crankshaft fractured.
Forced Landing
A forced landing was executed to unsuitable terrain approximately one-quarter mile from the runway.
Post-Accident Findings
Following the accident, the left engine was successfully test run. A teardown inspection of the right engine revealed the fractured crankshaft.