As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI FOR TAKEOFF, AILERONS JAMMED IN FULLY DEFLECTED POSITION WHILE PERFORMING "CONTROLS FREE AND PROPER" PRE-TAKEOFF CHECK. THE MECHANIC FOUND THAT THE CHAIN IN THE CONTROL COLUMN BROKEN ON THE PILOT SIDE, AND WHEN THE COPILOT DEFLECTED HIS CONTROL YOKE, IT PULLED THE BROKEN CHAIN INTO THE CHAIN SPROCKET JAMMING THE AILERON CONTROLS. PROBLEM IS CAUSED BY AN INSPECTION COVER ON THE BACK OF THE CONTROL YOKE.