But Gives Airlines Four Years To Comply With The AD

The FAA issued an Airworthiness Directive published in the Federal Register Tuesday which will require airlines to re-install emergency oxygen systems in their airplane's lavatories.

The AD (2012-11-09), state that the FAA is "superseding an existing airworthiness directive (AD) for certain transport category airplanes. That AD currently requires either activating all chemical oxygen generators in the lavatories until the generator oxygen supply is expended, or removing the oxygen generator(s); and, for each chemical oxygen generator, after the generator is expended (or removed), removing or restowing the oxygen masks and closing the mask dispenser door. This new AD requires installing a supplemental oxygen system in affected lavatories, which terminates the requirements of the existing AD. This AD was prompted by reports that the current design of the oxygen generators presents a hazard that could jeopardize flight safety."

The FAA says it is "issuing this AD to eliminate a hazard that could jeopardize flight safety, and to ensure that all lavatories have a supplemental oxygen supply."

While the AD is effective on August 10, the deadline for actually installing the O2 systems will not arrive for four years. In public comments, manufacturers such as Airbus, Boeing, Bombardier, Embraer, along with American Airlines (AA), Delta Air Lines, Southwest Airlines (SWA), United Airlines (UA), and All Nippon Airways (ANA), all requested that the FAA revise the NPRM to extend the 24-month compliance time. Airbus, Embraer, Air Line Pilots Association (ALPA) International, AA, and Boeing noted that the Lavatory Oxygen Aviation Rulemaking Committee (ARC) chartered on this subject established some notional life-cycle times from the initiation of a design through a fleet retrofit. The requested compliance time ranged from 36 to 60 months. The ARC considered even a 4-year compliance time aggressive. Commenters also noted that there are no actual designs at present; any schedule is at risk until the design is proven and validated.

But The Association of Flight Attendants (AFA) and ALPA encouraged the issuance of the final rule with the compliance times as proposed. AFA requested that interim measures also be incorporated. The commenters noted that the total time that lavatories will have been without oxygen would be about 3.5 years, even with a 24-month compliance time. AFA pointed out that the FAA's assessment of the safety risk was based on a finite time, and that we originally estimated a two- to four-year period to restore oxygen. Thus, retaining the proposed 24-month compliance time is appropriate.

The FAA disagreed with the compliance time request. Based on the number of affected airplanes and the lack of a design solution yet approved for any of them, the agency said a 24-month compliance time is not feasible. On the other hand, we acknowledge that compliance will be due later than the original estimate of a maximum of 4 years. But the adjusted compliance time is still within the confidence level of the risk assessment ... which was conservative ... conducted in support of AD 2011-04-09, Amendment 39-16630 in March of 2011.

FMI: AD in Federal Register