Incorrect rigging of flight control and trim systems has led to in-flight emergencies, accidents, and even deaths.
Four such mishaps within a 2-year span share common safety issues:
o Maintenance personnel who serviced or checked the systems did not recognize that the control or trim surfaces were moving in the wrong direction.
o Pilots who flew the airplanes did not notice the control anomalies during their preflight checks.
Anyone can make mistakes. In some cases, the mechanics who performed the work incorrectly were highly experienced
Mechanics: Prevent Misrigging Mistakes