AD 2021-03-18 Concerns The Assembly And Overhaul Of Certain Crew Oxygen Mask Stowage Boxes

The FAA is adopting a new airworthiness directive (AD) for all Dassault Aviation Model FALCON 7X airplanes.

This AD was prompted by a report of deviations concerning the assembly and overhaul of certain crew oxygen mask stowage boxes, including incorrect application of a certain thread-locker on the fitting sensor screws. This AD requires an inspection of certain crew oxygen mask stowage boxes for discrepancies, and replacement if necessary, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products. This AD becomes effective February 22, 2021.

Supplementary Information: The EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA Emergency AD 2021-0036-E, dated January 25, 2021 (EASA Emergency AD 2021-0036-E) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for all Dassault Aviation Model FALCON 7X airplanes.

This AD was prompted by a report of deviations concerning the assembly and overhaul of certain crew oxygen mask stowage boxes, including incorrect application of Loctite 222 threadlocker on the fitting sensor screws. The FAA is issuing this AD to address such deviations, which could lead to blocked oxygen supply flow to flight deck crew oxygen masks. In combination with inflight depressurization, flight deck smoke, or a smoke evacuation procedure, this lack of oxygen may lead to flightcrew hypoxia and loss of useful consciousness and consequent loss of control of the airplane. See the MCAI for additional background information.

FMI: www.regulations.gov