Eagle DW1 N8805X accident near Ider, Alabama

Probable cause

Fatigue failure of the No. 2 cylinder studs/through bolts and the fracture of the crankcase, which resulted in a total loss of engine power.

NTSB analysis

The commercial pilot was conducting an aerial application flight. He stated that while maneuvering at 1,500 ft, he heard a "deep knock" in the engine; the entire windshield became covered with oil, and the engine lost power. The pilot made a forced landing to a service road, during which the airplane struck a barbed-wire fence with the right wings before coming to rest in a field. Postaccident examination of the engine revealed the No. 2 cylinder had separated from the cylinder mounting deck. Two fractured sections of the left crankcase that included part of the No. 2 cylinder bore were found in the engine cowling. All but one of the No. 2 cylinder base studs and through bolts remained in the cylinder bore and were fractured. The fractured surfaces exhibited signatures consistent with fatigue. The fatigue failure of the No. 2 cylinder studs and through bolts and the fracture of the crankcase led to the loss of engine power.

Text from the NTSB. Open the NTSB docket for ERA18LA195 for the full record.