What was found
(CAN)A LOUD SCREECHING SOUND WAS HEARD ON DESCENT FOLLOWED BY ELECTRICAL BURNING ODOR AND SMOKE IN CABIN. MAINTENANCE CHECK FOUND AVIONICS COOLING FAN GRINDING & RIGHT PACK AIR CYCLE MACHINE COOLING BLADE S FAILED. AVIONICS COOLING FAN REPLACED, RIGHT PACK AIR CYCLE MACHINE P/N 757A0000-09 REPLACED AND GALLEY AREA INSPECTED FOR EVIDENCE OF OTHER ELECTRICAL FAULTS.