On August 24, 1993, a Mooney M20B (registration N74580) operated by Thomas N Thompson was involved in an aviation accident near Landover, MD. Investigators recorded the probable cause as: The propeller blade failed from fatigue. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During an ILS approach, the tip of a propeller blade separated, causing severe vibration. The right aileron became partially separated, making roll control difficult. The pilot shut down the engine, retracted the gear, and performed a wheels-up landing in a hilly field. Metallurgical examination revealed fatigue failure of the propeller blade.
Incident Details
While inbound to the outer marker on an ILS approach, the tip of a propeller blade separated, resulting in severe engine vibration. Additionally, the right aileron became partially separated, causing the pilot difficulty in maintaining roll control. The pilot shut down the affected engine and retracted the landing gear to reduce drag. After clearing obstacles, the pilot executed a wheels-up landing in a field characterized by hilly terrain.
Investigation
A metallurgical examination of the failed propeller blade revealed that the blade had failed due to fatigue. The examination provided the basis for determining the cause of the propeller blade separation.
Conclusion
The investigation concluded that the propeller blade failure was a result of fatigue. No other contributing factors were identified from the available evidence.