What was found
AIR TURNBACK/DECLARED EMERGENCY, CABIN ALTITUDE WARNING HORN AND LIGHT ILLUMINATED & SOUNDED WHILE AT CRUISE FLIGHT. R&R AFT OUTFLOW VALVE ASSEMBLY IAW AMM.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
AIR TURNBACK/DECLARED EMERGENCY, CABIN ALTITUDE WARNING HORN AND LIGHT ILLUMINATED & SOUNDED WHILE AT CRUISE FLIGHT. R&R AFT OUTFLOW VALVE ASSEMBLY IAW AMM.