Incident Summary
An instrument flight instructor and a student pilot experienced a failure of the directional gyro during flight. In response, they covered the failed instrument and requested to return to their departure airport. The aircraft was not equipped to fly the published approach for the intended landing. During the return, they requested a descent to an altitude below the base of the controller's radar coverage and disappeared from radar shortly thereafter.
Circumstances
The aircraft subsequently impacted tall trees while flying in a rainshower. Witnesses reported that the cloud base was at treetop level at the time of the accident. The instruments required for partial panel flight were found to be functional. No other discrepancies were noted with the aircraft or its systems.
Flight Details
The flight involved an instrument flight instructor and a student. The directional gyro failure prompted the crew to revert to partial panel procedures. They covered the inoperative instrument and coordinated with air traffic control for a return. The descent below radar coverage occurred before the collision with trees in low-visibility conditions.