Discussion
On June 18, 2012, at 77 FR 36216, the Federal Register published our notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR part 39 to include an AD that would apply to Eurocopter France Model AS350B, AS350BA, AS350B1, AS350B2, AS350B3, AS350C, AS350D, AS350D1, AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters with a bracket, part number (P/N) 158172, 158173, 158288, or 158289, installed. That NPRM proposed to require an initial and recurring inspection of the brackets for a crack, and if there was a crack, replacing the cracked bracket with an airworthy bracket. The proposed requirements were intended to prevent failure of the emergency flotation system and loss of float stability in the event of a water landing.
The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, issued EASA AD No. 2011-0072, dated April 20, 2011 (AD 2011-0072), to correct an unsafe condition for the Eurocopter AS350B, AS350BA, AS350BB, AS350B1, AS350B2, AS350B3, AS350D, AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters with Aerazur emergency flotation gear attachments installed. EASA stated it received several reports of cracks being found on the brackets which appear to be caused by stress corrosion. This condition, if not corrected, could result in ``rupture of the emergency flotation gear attachment brackets'' during a water landing. The helicopter's float stability could no longer be ensured, possibly resulting in damage to the helicopter and injury to the occupants. EASA's AD requires an initial inspection of the brackets, replacement of any brackets found with cracks, and re-inspection of the brackets every 13 months.
Comments
We gave the public the opportunity to participate in developing this AD, but we received no comments on the NPRM (77 FR 36216, June 18, 2012).
FAA's Determination
These helicopters have been approved by the aviation authority of France and are approved for operation in the United States. Pursuant to our bilateral agreement with France, EASA, its technical representative, has notified us of the unsafe condition described in the EASA AD. We are issuing this AD because we evaluated all information provided by EASA and determined the unsafe condition exists and is likely to exist or develop on other helicopters of these same type designs and that air safety and the public interest require adopting the AD requirements as proposed except we are incorporating a figure by reference instead of including it in our AD to meet current publication requirements. This change is consistent with the intent of the proposals in the NPRM (77 FR 36216, June 18, 2012) and will not increase the economic burden on any operator nor increase the scope of the AD.
Interim Action
We consider this AD interim action. Eurocopter is developing a modification that will address the unsafecondition identified in this AD. Once this modification is developed, approved, and available, we might consider additional rulemaking.
Differences Between This AD and the EASA AD
Differences between this AD and the EASA AD include:
The EASA AD applies to Eurocopter Model AS 350 BB helicopters. This AD does not as this model is not type certificated by the FAA. Additionally, the EASA AD excludes Eurocopter Models AS350C and AS350D1, whereas this AD includes them.
The EASA AD mandates different compliance times depending on the manufacture date of the helicopter. We mandate inspecting all helicopters within 110 hours TIS or 3 months, whichever occurs first, regardless of date of manufacture.
This AD does not require returning cracked brackets to the manufacturer.
Related Service Information
Eurocopter issued Alert Service Bulletin (ASB) No. AS350-05.00.63, Revision 1, dated April 18, 2011, and ASB No. AS355-05.00.58, Revision 1, dated April 18, 2011. TheseASBs specify procedures to inspect the front and rear brackets at regular intervals. EASA classified these ASBs as mandatory and issued EASA AD 2011-0072 to ensure the continued airworthiness of these helicopters.
Costs of Compliance
We estimate that this AD will affect 733 helicopters of U.S. Registry and that labor rates will average $85 an hour. Inspecting the brackets will take about 4 work-hours per inspection cycle for a labor cost of $340 per helicopter and $249,220 for the U.S. fleet. Replacing the bracket, if needed, will require about 1 work-hour and about $1,130 for the parts. Thus, the total cost to replace one bracket will be about $1,215.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: ``General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on helicopters identified in this rulemaking action.
Regulatory Findings
This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national
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government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatoryaction'' under Executive Order 12866;
(2) Is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
(3) Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction; and
(4) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared an economic evaluation of the estimated costs to comply with this AD and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.