What was found
DURING A JUMP RUN, WHILE IN CRUISE, THE LT ENGINE CHIP LIGHT FLICKERED MOMENTARILY & THEN THE ENGINE SHUT DOWN. RETURNED TO THE DEPARTURE & LANDED WITHOUT FURTHER INCIDENT. SUSPECT CATASTROPHIC FAILURE OF THE LT ENGINE. R & R ENGINE. ACFT RETURNED TO SERVICE. TEARDOWN OF FAILED ENGINE, DETERMINED THAT ONE OF THE GEARS ON THE TORQUE SENSOR DRIVE HAD A CATASTROPHIC FAILURE, BREAKING INTO THREE SECTIONS & DROPPED METAL TO THE BOTTOM OF THE GEARBOX. THIS CAUSED THE FUEL CONTROL DRIVE TRAIN TO STOP ROTATING, SHUTTING DOWN THE ENG. THIS PREVENTED THE SCAVENGE PUMP & OIL PUMPS FROM MOVING DEBRIS THROUGH THE REST OF THE ENGINE.