Airworthiness Directives; Boeing Model 737, 747, 757, 767, and 777 Series Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 737, 747, 757, 767, and 777 series airplanes. This action requires repetitive inspections of any chemical oxygen generators and/or passenger, attendant, or lavatory service unit assemblies of the passenger oxygen system that have been replaced, to verify correct installation of the release pin in the generator firing mechanism of the oxygen generator; and corrective action, if necessary. This action is necessary to find and fix incorrect installation of the release pin in the generator firing mechanism, which could result in the unavailability of supplemental oxygen and possible incapacitation of passengers and cabin crew during an in-flight decompression. This action is intended to address the identified unsafe condition.