What happened
During a preflight inspection of the aircraft, the pilot and mechanic confirmed that the engine oil quantity was satisfactory. Following a six-minute engine run-up that included numerous propeller cycles, the pilot commenced a flight consisting of one circuit around the traffic pattern. During the takeoff roll, both oil pressure and engine RPM remained within normal parameters.
After the landing gear was retracted and the aircraft had passed the departure end of the runway, the pilot observed that the oil pressure had dropped to zero. In response, the pilot entered a left downwind for runway 09, reduced throttle, and decided to perform a precautionary landing on runway 27. While executing a left descending turn on a close-in left base for runway 27 at an altitude of 200 feet, the pilot lowered the landing gear. Upon adding power to continue the approach, the engine failed to respond. The aircraft subsequently stalled, impacted the ground, and slid to a stop. There were no injuries reported.
The investigation
A post-accident examination of the engine revealed no evidence of pre-impact failure or malfunction. Investigators found no oil leakage from the engine; notably, the engine contained the same quantity of oil that had been reported during the preflight inspection. Furthermore, testing of the oil pressure gauge using air pressure confirmed that the instrument was operating correctly.