What happened
During an aerial application mission involving the spreading of superphosphate, a Fletcher experienced a mechanical failure that led to a fatal accident. Earlier in the day, following the 35th flight, the pilot noted that the elevator controls were sticking and prone to jamming when the control column was pulled back toward its limit. To address this, a crew member inspected the internal fuselage components while the pilot moved the controls. During this inspection, a small piece of 16-gauge metal was discovered in the lower elevator pulley and removed, after which flight operations continued.
Later that morning, at approximately 10:15, the ground crew observed that the aircraft's engine noise had stopped and discovered the wreckage on a ridge summit. The aircraft had struck the terrain in a steep, near-vertical dive. The impact occurred at an airspeed of 127 mph, as indicated by the instrument markings. The crash resulted in one fatality, involving the pilot. Aside from the nose wheel, all debris remained concentrated at the primary impact site, and no fire was reported following the collision.
Findings
Investigations into the wreckage determined that while the rudder and aileron systems remained functional, the lower elevator cable had been severed approximately 12 inches from its attachment point to the counterbalance. The failure was traced back to a loose No. 6 PK screw that had migrated into the groove of the lower elevator pulley. When the pilot attempted to pull back on the control column, the screw became lodged between the cable and the pulley guard pin, causing the elevator to lock. The physical force exerted by the pilot while attempting to recover from the dive caused the sharp edge of the screw head to cut through the cable.