What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS AT 17,000 TURNED OFF APU IAW PROCEDURE. CLIMED ON SINGLE PACK SINGLE SOURCE ON RIGHT PACK. NOTICED CABIN CLIMBING UNCONTROLABLE @ 30,000. INIATED DECENT TO 10,000 RT PACK WAS INOPERTIVE, INOP PACK OFF LIGHT ILLIMINATED ON GROUND AFTER LANDING. MAINTENANCE FOUND THE R/ACM TURBINE OUTLET DUCT SEPERATED, WITH THE UPPER DUCT SEAL ATTACHING CABLE SHEARED AND THE LOWER CABLE BALL PULLED THRU THE TURBINE MOUNTING CASTING. REMOVED AND REPLACED RIGHT PACK ACM IAW AMM 21-51-03. OPS AND LEAK CHECK GOOD. OK FOR SERVICE.