Accident Details
The aircraft was cleared for an NDB approach to Cadillac. Shortly after cancelling IFR, the aircraft crashed on the opposite side of the airport from the approach end of the runway. The pilot-activated runway lights were never turned on during the approach. The lighting system was newly commissioned and not yet on approach plates, but was included in a NOTAM.
Deviation from Procedure
A review of the aircraft's flight path showed that the aircraft was following the RNAV final approach course rather than the NDB final approach course. Additionally, a lighted Christmas tree farm was located adjacent to the airport.
Weather Conditions
The weather at the time was 300 feet overcast with one mile visibility. The official findings noted low ceiling and rain as contributing factors.
Investigation Findings
No evidence of mechanical malfunction could be found in the wreckage. The official probable cause findings include: inadequate preflight planning, improper use of procedures, failure to obtain NOTAMs, failure to maintain proper altitude, failure to perform a missed approach, and non-operating runway edge and end identifier lights. Pilot complacency and overconfidence were also cited. Both occupants were killed in the crash.