FAA requires US operators to reinstate oxygen systems in lavatories
The FAA is superseding an airworthiness directive (AD) with a final rule that directs operators to retrofit supplemental oxygen systems in lavatories on more than 5,500 US-registered aircraft, which will cost an estimated $44.2 million for US operators.
The agency's final rule, which is to be published in the Federal Register on 26 June, will require all lavatories to have a supplemental oxygen supply installed. This replaces a directive from March 2011 that required operators to expend each chemical oxygen generator's oxygen supply or remove them, and to remove or re-stow the oxygen masks.
Under the new AD, operators are required to install a supplemental oxygen system in each lavatory within 37 months from its effective date, which will be 45 days from when the rule is published.
The FAA's original AD 2011-04-09 that said that design of the chemical oxygen generators "presents a hazard that could jeopardize flight safety." The agency distributed individual notices to US operators on 10 February 2011 that made the directive immediately effective.
The FAA issued a notice of proposed rulemaking on 27 February that proposed installing the supplemental oxygen system in the lavatories affected by the AD after hearing comments from several operators and manufacturers, including Airbus, Boeing, Embraer, All Nippon Airways, American Airlines, Delta Air Lines, Southwest Airlines, United Airlines, Embraer and the Air Line Pilots Association.
Several airlines requested the FAA to extend its original compliance timeline of 24 months, citing the fact that designs for the retrofit do not exist yet, and the scope of the modification is extensive.
"We partially agree with the request," said the FAA in the AD. "Because of the lack of a retrofit design and the magnitude of the retrofit, and new configuration(s), on such a large number of affected airplanes, we agree that the proposed compliance time of 24 months is insufficient."
According to the notice of proposed rulemaking in February, when operators removed the chemical oxygen generators due to the original AD, they were no longer in compliance with federal aviation regulations. On 8 March 2011, a special federal aviation regulation permitted those US operators to keep flying with the disabled system until an FAA-charted aviation rulemaking committee recommended ways for restoring oxygen systems while also addressing the security vulnerability.