On June 18, 1983, a Cessna 195A (registration N1537H) was involved in an aviation accident near St. George, UT. Investigators recorded the probable cause as: Fatigue failure of the propeller blade originating at a subsurface inclusion. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A propeller blade separated, causing the aircraft to veer left out of control. The aircraft came to rest about 30 feet from the runway with the right main landing gear broken off. Metallurgical examination revealed fatigue failure.
Event Narrative
During operation, a propeller blade separated from the aircraft. This caused the aircraft to veer sharply to the left and become uncontrollable. The aircraft subsequently came to rest approximately 30 feet from the runway. The right main landing gear was found broken off.
Examination Findings
A metallurgical examination of the separated blade was conducted. The examination revealed that the blade failed due to fatigue. The fatigue crack originated at a subsurface inclusion. Additionally, a corrosion crack was present on the outer side of the blade. This crack exhibited corrosion products. The blades had been overhauled five months prior to the accident. During the overhaul, the blades were inspected for cracks using a dye penetrant test in accordance with the overhaul manual. An eddy current test was performed only on the inside of the bore.
Probable cause
Fatigue failure of the propeller blade originating at a subsurface inclusion.