What was found
GEARBOX WAS REMOVED FOR REPAIR AT EUROCOPTER CANADA LTD. THEY REPLACED ALL BEARINGS AND RETURNED THE REPAIRED GEARBOX. PART WAS INSTALLED IN ACFT AND DURING SUBSEQUENT GROUND MAINTENANCE RUNS, CHIPS APPEARED ON THE CHIP PLUG. ACFT NEVER GOT AIRBORNE. REMOVED GEARBOX FOR REPAIR AGAIN AT ECL. RE-INSTALLED REPAIRED GEARBOX AND AGAIN DURING SUBSEQUENT GROUND MAINTENANCE RUNS CHIPS APPEARED ON THE CHIP PLUG. REMOVED GEARBOX FOR REPAIR AT ECL. LOANER FROM AEC IS INSTALLED ON ACFT WHICH IS NOW IN SERVICE.