What was found
RIGHT BLEED TRIPOFF LIGHT ON AND A SECOND LATER LEFT BLEED TRIPOFF LIGHT ON. TOTAL LOSS OF CABIN PRESSURE. INITIATED EMERGENCY DESCENT PROCEDURES. ACCOMPLISHED PNEUMATIC SYSTEM TROUBLESHOOTING ON BOTH ENGINES. NUMBER ONE ENGINE TESTED GOOD. NUMBER 2 ENGINE HI-STAGE VALVE, HIGH STAGE REGULATOR AND PRESSURE REGULATING AND SHUT-OFF VALVE FAILED TEST. REPLACED ALL THREE COMPONENTS. UNDER INVESTIGATION.