Primary finding
Probable cause
the loss of engine power due to a cracked cylinder head.
Investigator assessment
Analysis narrative
The pilot reported the airplane lost engine power during an aerial application spray run. He made a forced landing on a soft field and the airplane nosed over. Examination of the engine revealed that the number seven cylinder head was cracked between the spark plugs.
Source record
Factual narrative
On July 27, 1993, about 1830 central daylight time, a Swizer G167B airplane, N6637Q, sustained substantial damage during a forced landing on a soft field near Borup, Minnesota. The solo commercial pilot was not injured. The aerial application flight operated under 14 CFR Part 137 without flight plan in visual meteorological conditions. The flight departed Ada, Minnesota, about 1845. The pilot reported a total loss of engine power during an approach to a field to begin aerial spraying. He made a forced landing in the field and the airplane nosed over in the soft terrain. An examination of the engine revealed the number seven cylinder head was cracked between the spark plugs. -