What was found
DURING INTIAL DESCENT, CABIN ALTITUDE WARNING WITH DEPRESSURIZATION FROM FL 340. CREW DONNED O2 MASK AND DECLARED AN EMERGENCY. PERFORMED EMERGENCY DESCENT , DIVERTED TO BAQ AND LANDED. MTX GROUNDED A/C. A/ C IS IN WORK, DURING T/S FOUND R PACK INOP, FOUND R FLOW CONT SOV CONN D1276 DISC. VALVE WAS LOCKED AND SAFETY TIED. RETURNED TO ORIGINAL CONFIGURATION PERFORMED BITE TEST AND CABIN PRESSURIZATION IAW AMM 21-31-00/01 FOUND NORMAL. AIRCRAFT RELEASE NO ETOPS. A/C RETURNED TO SERVICE.