What was found
WHILE IN FLIGHT/ FLIGHT CREW NOTICED SMOKE IN THE CABIN. LANDED AIRCRAFT SAFELY. MECHANICS FOUND OIL IN THE ENVIRONMENTAL BLEED AIR ON THE RT ENGINE. INSPECTED ENGINE AND FOUND LOOSE THRU BOLTS ON THE COMPRESSOR BEARING STUDS. REMOVED ENGINE SENT. DISASSEMBLED GEARBOX OF ENGINE. FOUND CRACKED ACCESSORY DRIVE HOUSING AT COMPRESSOR BEARING CARRIER THRU BOLTS. ALL THRU BOLTS LOOSE ALSO. ENGINE IS NOW UNDER EVALUATION.