Incident Overview
Shortly after departure, while the airplane was approximately 50 to 75 feet above the runway, one of the two blades on the left propeller detached. The FAA designee in the control seat took over and executed a landing with the landing gear extended, touching down on grass alongside the runway. The airplane continued off the paved surface and came to a stop in an upright position, with the nose landing gear having collapsed.
Examination
A post-incident inspection of the left propeller assembly revealed that the hub arm of blade No. 1 had fractured. The fracture surface exhibited characteristics consistent with fatigue cracking.
Maintenance Records
Review of the propeller's maintenance history showed that the last overhaul was completed on October 18, 1985. Since manufacture, the propeller had accumulated a total of 2,979.7 hours of operation, with 963.2 hours having been logged since the most recent overhaul.