EASA AD US-2018-23-13: Oxygen - Flightcrew Oxygen Masks - Inspection / Replacement

What to do

Operators of Boeing 747-8 and 747-8F airplanes must inspect the flightcrew oxygen masks and regulators to determine if affected part numbers are installed and replace them as specified by Boeing Special Attention Service Bulletin 747-35-2133, Revision 1. Compliance with this directive is mandatory by January 2, 2019. Operators should also follow FAA-approved procedures for any subsequent modifications involving oxygen mask parts.

Summary

Federal Aviation Administration Airworthiness Directive 2018-23-13 is a final rule applicable to all Boeing Model 747-8 and 747-8F series airplanes. It addresses an unsafe condition where flightcrew oxygen masks and regulators did not function as designed during flight testing, potentially delaying mask deployment. This directive mandates inspection and replacement of certain oxygen masks and regulators to ensure proper functionality.

What changed

This new airworthiness directive introduces a requirement for operators to inspect flightcrew oxygen masks and regulators to identify specific part numbers and replace them if necessary. It removes the need to inspect oxygen mask stowage boxes and provides alternative corrective actions to reduce the need for alternative method of compliance requests. The directive also clarifies installation limitations for replacement parts to maintain compliance.

Why it matters

This directive is critical for aviation professionals because malfunctioning flightcrew oxygen masks can delay emergency oxygen supply, increasing the risk of hypoxia and loss of consciousness during flight. Operators, maintenance, and compliance teams must ensure affected equipment is inspected and replaced promptly to maintain flight safety and regulatory compliance. Failure to comply could result in unsafe flight conditions and regulatory penalties.

What to do

Summary

What changed

Why it matters

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