Introduction
On October 29, 2024, about 1426 central daylight time, a Beech 58 airplane, N811PB, was destroyed in an accident near Arlberg, Arkansas. The pilot, who was the sole occupant, sustained fatal injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Pre-Accident Events
Earlier that morning, the pilot flew the airplane from Roscoe Turner Airport (CRX), Corinth, Mississippi, to Drake Field Airport (FYV), Fayetteville, Arkansas, for an avionics inspection. The purpose was to troubleshoot an intermittent autopilot issue involving a slow pitch oscillation with the autopilot engaged and a 100 ft out-of-trim condition upon disengagement.
An avionics technician inspected the autopilot pitch servo and pitch trim servo. He found two loose bolts on the autopilot pitch servo capstan assembly and noted that the elevator pitch control bridle cable appeared overtightened. The autopilot pitch servo was removed for bench testing and not reinstalled before the accident flight. Additionally, the technician discovered fraying on the nose-up pitch trim cable, which he documented with photos and shared with the pilot.
Technician's Work
The technician expressed concern that the frayed cable could fail in flight and advised replacement. The pilot, however, dismissed the severity, stating the cable was "not that bad" and that he had "seen worse cables." The pilot indicated he would have his aviation mechanic replace the cable but intended to fly the airplane without any repairs. The technician, worried about imminent failure, installed a single length of 0.041-inch safety wire to "bridge" the frayed section. He positioned the pitch trim to neutral, applied super glue to secure frayed wires, and routed the safety wire from the rear turnbuckle, under the pulley guard at the pitch trim servo capstan, to two turnbuckles forward of the servo. The technician acknowledged that this was not standard protocol but was intended to keep the cable tethered if it failed. He also pulled and collared the autopilot and pitch trim circuit breakers and instructed the pilot not to use manual pitch trim. No ferry permit was discussed, and the workorder was closed without cable replacement.
Departure and In-Flight Emergency
The pilot departed FYV at 1355. According to ADS-B data, the airplane climbed to about 9,000 ft msl en route to CRX. At 1422:03, the pilot reported "trim issues" to air traffic control and requested vectors to the nearest airport with a 5,000 ft runway. At 1424:10, he declared an emergency, stating, "we are using all of our energy to overcome the trim." His final transmission at 1424:56 noted "one soul on board, four hours of fuel." No further communications were received. ADS-B data ended at 1426:09, showing the airplane at 1,575 ft msl (170 ft AGL), 203 knots calibrated airspeed, descending at about 1,800 ft/min with a 6.7° right-wing-down roll and -4.7° flight path angle.
Wreckage Examination
The airplane struck trees in a wings-level attitude and fragmented over a 245 ft debris path. Flight control continuity was established for rudder and elevator bellcranks; aileron continuity showed overload separations. The autopilot and pitch trim circuit breakers were found pulled-and-collared. The pitch trim cables had three separations: one aft of the pitch trim servo and two at the horizontal stabilizer forward spar. The left pitch trim actuator indicated 10° to 15° nose-down; the right actuator indicated 10° nose-up. The safety wire was attached to turnbuckles on both the nose-up and nose-down pitch trim cables, inconsistent with the technician's description of bridging only the frayed section. The routing would have precluded nose-up trim positions, as the safety wire would become taut near neutral, preventing further cable movement in the nose-up direction.
Conclusion
The accident investigation did not state a probable cause.