What happened
During an approach, the flight instructor (CFI) initiated a training maneuver by simulating a loss of power in the right engine. As part of this simulation, the CFI pulled the circuit breaker for the normal landing gear extension system. The student attempted to extend the landing gear using the alternate system; however, the left gear failed to reach the down-and-locked position.
The instructor attempted to reset the situation by reinserting the circuit breaker and cycling the gear, but the left gear remained unlatched. Due to the gear malfunction, the CFI ordered a go-around. At approximately 300 feet above ground level (AGL), the crew advanced the throttles, at which point the instructor noted an actual lack of power in the right engine and took control of the aircraft.
While the instructor attempted to restore full power to the right engine, the engine produced only limited thrust. The propeller was not feathered. Although the aircraft initially maintained level flight, it was unable to climb and eventually began to descend. This resulted in a forced landing on rough desert terrain. There were no injuries reported.
The investigation
A subsequent investigation was conducted to determine why the right engine lost power. Investigators found no reason for the reported loss of engine power.