Accident Overview
On August 29, 2018, at approximately 1130 central daylight time, a Grumman G-164A airplane (registration N956X) suffered a complete loss of engine power while maneuvering over an open field near Opelousas, Louisiana. The private pilot, operating the aircraft under 14 CFR Part 91 as a personal flight, executed an off-airport forced landing in the field. The pilot reported no injuries. The airplane incurred substantial damage to the top wings and vertical stabilizer.
Flight Details
The flight had departed from Church Point, Louisiana, around 1100 local time. Visual meteorological conditions prevailed at the accident site, and no flight plan had been filed. The pilot was practicing crop dusting maneuvers when the engine lost all power, according to his accident report.
Forced Landing and Damage
Being at low altitude, the pilot performed a forced landing in an open, muddy rice field. During the landing, the airplane nosed over, resulting in substantial damage to the top wings and vertical stabilizer.
Post-Accident Examination
Examination of the engine after the accident revealed that two of the three bolts securing the left magneto had come loose and were missing. The safety wire was also broken. The left magneto was barely attached, and the Sims coupling was heavily damaged. An FAA inspector reported that the magneto could be easily moved. The magneto, an American Bosch SB9RU-3 (serial number BB3829), had been installed on January 13, 1998.
The source states that the loose and missing bolts disrupted the spark timing, resulting in a complete loss of engine power.