What was found
CREW REPORTED THAT THE NR 1 PACK WOULD NOT HOLD CABIN PRESSURE WHILE EN ROUTE TO LAS AT FL 270 CABIN CLIMBED TO 9650 FL. CREW PERFORMED EMERGENCY DESCENT TO 10,000 FLT. AT 10,000 FLT CABIN ALT WAS 5500FT. AIRCRAFT LANDED IN LAS WITHOUT FURTHER INCIDENT. MX R & R NR 1 PACK CONDENSER DUE TO FAILURE IAW AIRBUS MM 21-52-32. OPS CHK OK. VENDOR CONFIRMS FAILURE. FOUND A BLOWN PAN ON UNIT. UNIT WAS CLEANED, RECORED AND PASSED ALL TESTS. REPAIRS WERE ACCOMPLISHED IAW OHM/CMM 21-52-10 REV.6.