What was found
FLT 1306, IAD TO JFK, APPROX 1700Z, ODOR (COCKPIT) & SMOKE DETECTED ON INITIAL CLIMB. RETURNED TO FIELD (IAD) PACK 1 FAIL ANNUNCIATED UPON ARRIVAL AT GATE. PERFORMED OPERATIONAL TEST OF COOLING PACKS PER 21-51-60-05. FOUND NR 1 LEFT ACM MAKING GRINDING NOISE AND NR 1 PACK SYSTEM ONLY PRODUCING HOT AIR. SUSPECT AIR BEARING SEIZURE AT ACM. REMOVED AND REPLACED LT NR 1 AIR CYCLE MACHINE AS PER AMM 21-51-05, PERFORMED OPS CHECK. NO ODOR FROM PACKS. OK FOR SERVICE.