Background
The pilot and passengers were returning to Ithaca, NY, after a business trip to Indiana. The pilot departed under visual flight rules (VFR) but later received an instrument flight rules (IFR) clearance due to deteriorating weather conditions near the destination.
Sequence of Events
While at an altitude of 5,000 feet and being vectored to the final approach course for the VOR approach to Runway 14, the pilot reported that he 'just lost the gyros.' Radio and radar contact were lost shortly after this report.
Wreckage and Investigation
The wreckage was located four days later in a wooded area. Examination of the engine-driven vacuum pump revealed it was capable of normal operation. The artificial horizon was inspected, and investigators found dirt packed in the filter and evidence of poor maintenance. The quality control inspector for Mid Continent Instrument Company opined that 'this unit was not reliable enough to fly with.'
The pilot's personal flight time logbook was not recovered, so instrument proficiency could not be determined.
Technical Findings
The vacuum pump functioned normally, but the artificial horizon exhibited signs of inadequate maintenance, including a clogged filter and general poor condition.