EASA AD US-2022-04-09
SUPERSEDED BY FAA AD 2023-13-11
Summary
FAA Airworthiness Directive 2022-04-09 is a final rule addressing certain AVOX System Inc. (formerly Scott Aviation) oxygen cylinder and valve assemblies installed on various transport airplanes, including Boeing 737 Next Generation and 777 series models. The directive targets assemblies with oxygen leakage caused by improper spacing between valve components, which could lead to insufficient oxygen supply or ignition risks during depressurization events.
What Changed
This new airworthiness directive requires inspection of oxygen valve assemblies and cylinder assemblies to identify affected serial numbers. For assemblies with certain serial numbers, it mandates a detailed inspection of the gap between the packing retainer and valve body, and replacement of assemblies with unacceptable gaps. It also requires reporting and returning affected parts to the manufacturer.
Why It Matters
This directive is critical for aviation professionals to prevent oxygen leakage that could compromise crew and passenger safety during emergencies. Operators and maintenance organizations must ensure affected parts are inspected and replaced promptly to maintain airworthiness and regulatory compliance. The directive also clarifies inspection requirements to avoid confusion regarding component serial numbers and applicability.
What To Do
Operators must inspect installed oxygen cylinder and valve assemblies within 60 days of the directive's effective date, April 4, 2022, to identify affected serial numbers. Assemblies with unacceptable gaps must be replaced before further flight. Spare parts must be inspected before installation. Additionally, affected parts must be reported and returned to AVOX Systems Inc. as specified.
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.