Incident Overview
A pilot contacted Phoenix Approach Control and requested radar advisories to Deer Valley Airport (DVT). The request was granted, and the flight received radar service. When the aircraft was approximately 7 miles west of DVT, the radar advisories were terminated. Moments later, the pilot reported that the cockpit had filled with smoke and that he intended to land on a road.
Pilot Actions
The pilot's communication with air traffic control indicated a sudden emergency. After the termination of radar advisories, the pilot's report of smoke in the cockpit and the decision to land on a road were the only additional details provided. No further communications were recorded.
Engine Examination
Inspection of the engine after the event disclosed that the No. 4 connecting rod had failed due to a lack of lubrication. The engine oil sump was found intact but did not contain any oil. Additionally, there was no evidence of oil stains on the airplane's fuselage or wings, suggesting that the oil loss did not occur externally. The absence of oil in the sump and the lack of external oil stains indicate that the oil was consumed or lost internally, leading to the connecting rod failure.