What was found
DURING CLIMB CREW ENCOUNTERED A LEVEL 3 CABIN ALT ALERT ALONG WITH NR 2 AND NR 3 BLEED FAIL AND NR 3 PNEUMATIC MANIFOLD FAIL. FOLLOWED PROCEDURES, EMERGENCY DESCENT AND DUMPED FUEL (38000 K) FOR ACCEPTABLE LANDING WEIGHT. AIRCRAFT RETURNED TO SCL WITH NORMAL LANDING. NR 3 PNEUMATIC MANIFOLD FAIL. NR 3 BLEED FAIL, LVL 2 MESSAGE. NR 2 BLEED FAIL, LVL 2 MESSAGE. REPAIRED DUCT LEAK (LOOSE CLAMP) IAW MD11 AMM 20-10-11. LVL 3 CABIN ALT ALERT. RTS TO CABIN PRESSURE CONTROLLER IAW MD11 AMM 21-31-00. NO FAULTS. AIRCRAFT RETURNED TO SERVICE.