What was found
LEFT ENGINE LOST POWER IN-FLIGHT. AIRCRAFT LANDED WITH NO INCIDENT. NO DETERMINATION MADE, UNIT MUST BE TORN DOWN TO INSPECT. SOUNDS LIKE BAD BEARINGS WHEN MOTORED BY STARTER. ACFT LOST POWER IN-FLIGHT. LANDED SAFELY AT SHEBOYGAN, WINCONSIN. PILOT REPORTED ENGINE DECREASED IN POWER, BUT WAS SHUT DOWN AS A PRECAUTION. ENGINE REMOVED FOR DISASSEMBLY AND INSPECTION. ENGINE MOTORED ON GROUND WITH STARTER. SOUNDED LIKE COMPRESSOR BLADES WERE DRAGGING. METAL CONTAMINATION FOUND IN EXHAUST STACKS.