What was found
(CAN) DURING DAILY INSPECTION THE AME NOTICED BLACK GREASE COMING FROM BOTTOM SURFACE OF SWASHPLATE. SWASHPLATE REGREASED AND AIRCRAFT RETURNED TO SERVICE. APPROXIMATELY 1.5 HOURS INTO FLIGHT A 'HOWLING' NOISE HEARD. AME FOUND EXCESSIVE BLACK GREASE IN SAME AREA. ALL LINKS DISCONNECTED AND SWASHPLATE CHECKED FOR ROTATIONAL SMOOTHNESS. EXCESSIVE ROUGHNESS FELT, LOWER BEARING WAS ROTATING IN OUTER RING.