As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 115 - HMO-MEX - AIRCRAFT RETURNED TO PLATFORM AS CONSEQUENCE OF PRESSURIZATION PROBLEMS. BOTH AIR CONDITIONING PACKAGES FAIL DURING FLIGHT, RECOVERING LEFT PACKAGE DURING DESCENT. CHECKED THE OPERATION OF THE PRESSURIZATION CONTROL VALVE AND CONTROLLERS RECOVERING THE RIGHT PACKAGE. TESTS WERE PERFORMED IAW MM 21-32-3 AND 21-32-5. (M)