On August 17, 1982, a Snow AT-301A (registration N2321V) operated by Farmers Flying Service was involved in an aviation accident near Leachville, AR. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 2 related events involving the same aircraft type or operator are linked below.
A pilot reported losing elevator control during a procedure turn, leading to a ground impact and cartwheel. Investigation found a bolt connecting the elevator horn and actuator tube had fallen out; the nut had backed off.
Incident Summary
A pilot reported that while performing a procedure turn for the third swath run, elevator control was lost. The aircraft subsequently impacted the ground and cartwheeled.
Investigation Findings
Examination of the aircraft revealed that the bolt connecting the elevator horn assembly to the elevator actuator tube had fallen out. The nut on that bolt had backed off from the threads. The assembly specification calls for a self-locking nut, which was not indicated as having been used. There had been no recent maintenance in the area of the elevator control linkage.
The investigation concluded that the missing bolt was the result of the nut backing off, leading to separation of the elevator control linkage. The design requirement for a self-locking nut was identified as a relevant factor, though no determination was made regarding whether the installed nut met that specification.