What was found
AIRCRAFT DEPARTED GJT. WHEN THE ENGINE BLEEDS WERE SELECTED ON, THE CABIN AND COCKPIT BEGAN TO FILL WITH SMOKE. THE AIRCRAFT RETURNED TO GJT. AFTER TROUBLESHOOTING AND A TEST FLIGHT, IT WAS DETERMINED THE NR 2 ENGINE WAS LEAKING OIL INTERNALLY INTO THE BLEED AIR SYSTEM. THE TURBOMACHINE WAS REPLACED. GROUND RUNS AND ANOTHER TEST FLIGHT WERE PERFORMED WITH NO DISCREPANCIES NOTED. AIRCRAFT RETURNED TO SERVICE.