What was found
DURING DESCENT, AT APPROXIMATELY 11,000 FEET, THE CREW NOTICED A STRONG BURNING SMELL IN THE COCKPIT AND CABIN WITH THE LT PACK GOING TO FULL HOT WHICH BECAME UNCONTROLLABLE IN EITHER AUTOMATIC OR MANUAL MODES. AN AUTOMATIC SHUTDOWN OF THE PACK OCCURRED. THE AIRCRAFT LANDED SAFELY. MAINTENANCE REMOVED AND REPLACED THE LT AIR CYCLE MACHINE AND ALSO THE COMPRESSOR DISCHARGE OVERTEMP SWITCH. OPERATIONAL CHECKS GOOD. AIRCRAFT OK FOR SERVICE.