Incident Description
While cruising at 5,000 feet in visual meteorological conditions, the pilot observed that the right engine spinner appeared unusual. He reduced the throttle but could not identify the issue, so he secured the engine. A tear in the spinner was later identified. The pilot restarted the engine but shut it down again due to a vibration. He advised air traffic control that the engine was secured and that he needed to divert.
On short final approach, the pilot realized the airplane was too high to reach the intended touchdown point. With the airplane sinking excessively, he decided to execute a go-around. He advanced the throttle on the left engine, and the airplane rolled right, then impacted trees.
Examination Findings
Post-incident inspection of the right spinner revealed a 1/2-inch crack that originated at its base and ran perpendicular to the propeller rotation. The crack had transitioned into a tear. The fracture surface exhibited a grayish color, consistent with fatigue.
Pre-flight Checks
The Pilot's Operating Handbook (POH) specifies that before flight, pilots should check the propeller and spinner for "nicks, security and oil leaks." The recommended safe single-engine speed for the airplane is 92 knots.