EASA AD US-2023-13-11
SUPERSEDED BY FAA AD 2024-19-15
Summary
Airworthiness Directive 2023-13-11 is a final rule issued by the FAA addressing certain AVOX Systems Inc. (formerly Scott Aviation) oxygen cylinder and valve assemblies, as well as oxygen valve assemblies installed on various transport category airplanes including Boeing models. This directive requires inspections to determine serial numbers and detailed inspections of the gap between the packing retainer and valve body, with replacement of assemblies found to have unacceptable gaps. It also limits installation of affected parts and mandates reporting and returning certain assemblies to the manufacturer.
What Changed
AD 2023-13-11 supersedes AD 2022-04-09 by expanding the list of affected assemblies and parts subject to inspection and replacement due to oxygen leakage risks. It continues to require detailed inspections and introduces installation limitations and reporting requirements. Minor editorial changes and paragraph redesignations were also made without increasing economic burden.
Why It Matters
This directive is critical for aviation professionals to prevent oxygen leakage from cylinder and valve assemblies, which could lead to insufficient oxygen supply during depressurization events or ignition risks due to heating or flow friction. Operators and maintenance teams must ensure compliance to maintain aircraft safety and airworthiness. The expanded scope means more assemblies must be inspected and potentially replaced, impacting maintenance planning and parts management.
What To Do
Affected operators must inspect oxygen cylinder and valve assemblies to determine serial numbers and perform detailed gap inspections where applicable. Assemblies with unacceptable gaps must be replaced, and installation of affected parts is restricted under certain conditions. Inspection results must be reported, and certain assemblies returned to the manufacturer. Compliance with this AD is required by September 5, 2023.
Your fleet's weekly compliance brief
AI-summarized regulatory changes, compliance deadlines, and action items — filtered to your aircraft, every Monday.
AI-generated summary from official EASA source document. Always verify against the original.