Incident Overview
During approach, the airplane's nose landing gear failed to extend. The pilot reported pitching the airplane up and down in attempts to extend the gear. During these maneuvers, the propeller began cavitating. The pilot noted a loss of oil pressure as the airplane neared the runway. Believing he could land, the pilot shut down the engine. Subsequently, the airplane "just quit flying" and struck the ground approximately 150 yards short of the runway threshold.
Post-Accident Inspection
Examination of the airplane revealed an open oil sump quick-drain fitting and a fractured nose gear retracting actuator arm. The bottom of the airframe was coated with oil. Approximately 50 percent of the arm's fracture surfaces exhibited corrosion.
Component Analysis
Representatives from the airframe manufacturer stated that failure of the actuator arm allows the landing gear to move freely within the nose gear well. They noted that the quick-drain fitting's finger-holds can be contacted by the nose gear when the airplane is pitched up and down.
The propeller manufacturer indicated that when oil supply stops, the propeller moves to a high blade angle. They added that a rotating propeller generates considerable drag.