Uncommanded Roll Incidents Linked to Spoiler Cable Misrouting (N9348)

Maintenance and Initial Incidents The aircraft had completed scheduled maintenance at an FAA-certified Class IV repair station, during which spoiler control cables 17B and 18B were disconnected and reconnected. The aircraft was released for service and flew 52 flights before the first incident, in which it experienced an uncommanded roll with the right wing dipping excessively. Maintenance action was taken, and the aircraft was returned to service. ## Subsequent Incidents and Findings Five flights later, the aircraft abruptly rolled right again. Maintenance found the right inboard spoiler cables extremely loose and re-rigged them. Sixteen flights later, another uncommanded right roll occurred. The investigation determined that cable run 17B was riding on the lower side of the pulley for cable 18B and running between the cable guards at that pulley. Testing showed the 17B cable could be pulled down and positioned into the lower 18B roller slot by hand, without disassembling parts or cable guides. A search of a maintenance database found no previous occurrences of cable misrouting in this area. The aircraft was returned to service, and no further flight control roll problems were noted after a year of flying.