A BEECH 1900 WAS DISPATCHED IN NON COMPLIANCE WITH THE R AILERON TRIM TAB COTTER PINS NOT SAFETY WIRED AFTER INSTALLATION.

Narrative

ON THE MORNING IN QUESTION; MYSELF; 2 OTHER MECHS AND AN INSPECTOR (WHO WAS ASSISTING WITH THE WORK) REMOVED; BALANCED AND REINSTALLED A L-HAND AILERON. (THIS WAS 3 WKS PRIOR TO THE ACTUAL DATE IT WAS DISCOVERED). AFTER INSTALLATION OF THE AILERON AND CONNECTING THE TRIM TAB; THE INSPECTOR LOOKED IT OVER (VERY QUICKLY) AND SIGNED IT OFF AND RELEASED IT FOR SVC. THE INSTALLATION OF THE AILERON WENT THROUGH UNEVENTFULLY. APPROX 3 WKS LATER; I FOUND OUT THE ACFT WAS AT THE LINE WHEN A PLT FOUND THE DISCREPANCY AND WROTE IT UP IN THE LOG. MAINT WAS CALLED AND THEY INSTALLED 2 COTTER PINS IN THE TRIM TAB WHICH WERE MISSING. I BELIEVE THAT THE INSPECTOR INSPECTING HIS OWN WORK; ALSO HAVING BEING SLEEP DEPRIVED; AFFECTED HIS ABILITY TO SEE MY ERROR. I BELIEVE MY TRAINING WAS ADEQUATE; BUT THAT IN MY EXPEDIENCY I OVERLOOKED THE BASIC LINE OF SAFETY -- THE COTTER PINS. WITH THAT SAID; I DID SAFETY WIRE THE TRIM TAB BUT MISSED THE COTTER PINS. AT THIS POINT I CANNOT ABSOLUTELY WITHOUT A DOUBT SAY ONE WAY OR ANOTHER IF THE COTTER PINS WERE INSTALLED WITH AN INSPECTOR HAVING LOOKED OVER IT.