Federal Aviation Administration March 25, 2024 – Federal Register Recent Federal Regulation Documents

The FAA proposes to supersede Airworthiness Directive (AD) 2023-13-11, which applies to certain AVOX Systems Inc. (formerly Scott Aviation) oxygen cylinder and valve assemblies; and oxygen valve assemblies; installed on but not limited to various transport airplanes. AD 2023-13-11 requires an inspection of the oxygen valve assemblies, and oxygen cylinder and valve assemblies, to determine the serial number of the valve, cylinder, and entire assembly; and for certain assemblies and parts, a detailed inspection for correct spacing of the gap between the bottom of the packing retainer and top of the valve body on the assemblies and replacement of assemblies having unacceptable gaps. AD 2023-13-11 also limits the installation of affected parts under certain conditions and requires reporting inspection results and returning certain assemblies to the manufacturer. Since the FAA issued AD 2023-13-11, the manufacturer identified additional assemblies and parts subject to the unsafe condition. This proposed AD would continue to require the actions specified in AD 2023-13-11 and require similar actions for those additional assemblies and parts. The FAA is proposing this AD to address the unsafe condition on these products.

The FAA proposes to adopt a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD-100-1A10 airplanes. This proposed AD was prompted by the discovery of a single-point failure within the left-hand and right-hand heater current monitor (HCM) units. This proposed AD would require installing a monitor circuit comprising relays external to the HCM units. This proposed AD would also require revising the normal and non-normal procedure sections of the existing airplane flight manual (AFM) to add new procedures associated with revised crew alerting system (CAS) messages. The FAA is proposing this AD to address the unsafe condition on these products.

The FAA proposes to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 777 airplanes. This proposed AD was prompted by a determination that the nitrogen enriched air distribution system (NEADS) cover plate assembly attached to a certain vent stringer in the center wing tank was installed without a designed electrical bond. This proposed AD would require installing electrical bonding and grounding, installing the cover plate assembly with new fasteners, and revising the existing maintenance or inspection program, as applicable, to incorporate new airworthiness limitations. The FAA is proposing this AD to address the unsafe condition on these products.

These special conditions are issued for the Airbus SAS (Airbus) Model A350 series airplanes. These airplanes will have a novel or unusual design feature when compared to the state of technology envisioned in the applicable airworthiness standards. This design feature is seats with inertia locking devices (ILD). The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.