What was found
AIR TURNBACK, DURING CLIMB OUT AT APPROXIMATELY 21,000 CABIN WARNING HORN CAME ON-CABIN APPROXIMATELY 10-11000FT. DESCENDED AND RETURNED TO PHX. R&R NR 2 ENGINE HIGH STAGE REGULATOR PER MM.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
AIR TURNBACK, DURING CLIMB OUT AT APPROXIMATELY 21,000 CABIN WARNING HORN CAME ON-CABIN APPROXIMATELY 10-11000FT. DESCENDED AND RETURNED TO PHX. R&R NR 2 ENGINE HIGH STAGE REGULATOR PER MM.