What was found
PHOG - FLT 578 - DURING CLIMB, COCKPIT FILLED WITH SMOKE. PERFORMED AIR TURN-BACK. PERFORMED INSPECTION OF PACK SYSTEMS, INSPECTED ENGINES FOR LEAKS, NO EICAS MESSAGES. AIRPLANE WAS INSPECTED AND FOUND TO BE SAFE FOR A NON-REVENUE FLIGHT BACK TO MAINLAND U. S. FOR MAINTENANCE. NOTE: AT IND, NR 2 ENGINE WAS REMOVED. REASONS: OIL LEAKAGE COMING FROM NOSE CONE BEARING FORWARD OF FAN.