Amateur-built CCX-2000 N57FX accident near Roll, Arizona

Probable cause

The loss of engine power due to a fatigue failure of the crankshaft for reasons that could not be determined based on the available information.

NTSB analysis

The pilot reported that, during cruise flight, the engine began to run rough and he attempted to troubleshoot; shortly thereafter, oil pressure decreased to 0 and the engine began to vibrate before it lost all power. The pilot performed a forced landing, during which the airplane struck a ditch and nosed over, substantially damaging the left wing.

Examination of the engine revealed that the crankshaft was fractured in fatigue aft of the No. 3 connecting rod journal, adjacent to the counterweights. Both counterweights were in place and remained attached to the crankshaft. Detailed examination of the fractured crankshaft revealed some non-conformances in the geometric tolerances of several crankcase attributes, and polishing was observed on the crankcase saddle bore landings; however, none were deemed severe enough to cause the crankshaft to fail in the time and manner in which it occurred. The cause of the crankshaft failure could not be determined based on the available information.

Text from the NTSB. Open the NTSB docket for WPR19LA070 for the full record.