Airworthiness Directives; The Boeing Company Airplanes

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 747-8 series airplanes. This AD requires an inspection to determine if all oxygen components in the passenger oxygen system are installed, installation of new o-rings, and corrective actions if necessary. This AD was prompted by a report that oxygen tube couplings in the passenger oxygen system could be missing or incorrectly installed. We are issuing this AD to detect and correct oxygen leaks from oxygen tube couplings in the passenger oxygen system, which could result in depletion of emergency oxygen at a faster rate than expected, reduce the passengers' and crews' protection from hypoxia at elevated cabin altitudes, and increase the risk of a fire.