What was found
RT PNEUMATIC SYSTEM FAILED DURING CLIMB, SO RT PNEUMATIC CABIN DEPRESSURIZED AND PASSENGERS OXYGEN MASKS WERE ACTIVATED. CAPTAIN PERFORMED ABNORMAL PROCEDURE DESCENDING AT 25,000 FEET. DURING MAINTENANCE CHECK, THE OXYGEN MASKS AND 25 OXYGEN GENERATORS WERE DETECTED ACTIVATED. AIRCRAFT WAS SENT TO THE HANGAR AND AUGMENTATION VALVE, 25 OXYGEN GENERATORS AND PRESSURE SWITCHES WERE REPLACED IAW MM 36-10-01, 35-22-01 AND 21-31-09; TESTS WERE PERFORMED IAW MM 36-10-00, 21-32-00, 35-20-00 AND 21-32-00, ALL CORRECT.