What was found
DURING OVERHAUL OF THE NLG FOUND THE BOLT WHICH HOLDS THE CENTERING CAMSHAFT TO THE NLG STRUT SHEARED AT THE THREADS. THE HEAD, SHANK AND THREADS OF THE BOLT REMAINED IN THE CENTERING CAMSHAFT BUT CAUSED MINOR WEAR TO THE UPPER TUBE ASSY AND CENTERING CAMSHAFT. COMPLETE FAILURE OF THE BOLT WOULD HAVE RESULTED IN THE NLG SEPERATING FROM THE AIRCRAFT DURING FLIGHT. THE BOLT FAILURE APPEARS TO BE RELATED TO A POOR DESIGN. THE SELECTED SHOULDER BOLT LENGTH DOES NOT PROVIDE BEARING ON BOTH SIDES OF THE CENTERING CAMSHAFT RESULTING IN THE BOLT THREADS BEING PLACED IN BENDING. I WOULD SUSPECT MANY OF THESE BOLTS ARE BROKEN IN OTHER NLG STRUTS ON LC41550FG AIRCRAFT.