Discussion
On April 22, 2013, at 78 FR 23692, the Federal Register published our notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR part 39 by adding an AD that would apply to Eurocopter France (now Airbus Helicopters) Model AS350B, BA, B1, B2, B3, D; and AS355E, F, F1, F2, and N helicopters with a T/R blade, part number (P/N) 355A12-0040- 00, 355A-12-0040-01, 355A12-0040-02, 355A12-0040-03, 355A-12-0040-04, 355A12-0040-05, 355A-12-0040-07, 355A-12-0040-08, or 355A12-0040-14, all serial numbers (S/N); or P/N 355A12-0050-04, 355A12-0050-10, or 355A12-0050-12, with a S/N 8400 through 9224. The NPRM proposed to require installing additional rivets to secure each tab, and inspecting for evidence of debonding of the tab after the rivets are installed. The proposed requirements were intended to prevent loss of a T/R blade tab, which could result in excessive vibration and loss of control of the helicopter.
The NPRM was prompted by ADNo. F-2004-178, dated November 10, 2004, issued by the Direction Generale de l'Aviation Civile (DGAC), which is the aviation authority for France, for Model AS350B, BA, BB, B1, B2, B3, and D helicopters, fitted with certain T/R blades. The DGAC also issued AD No. F-2004-176, dated November 10, 2004, for Model AS355E, F, F1, F2, and N helicopters with certain T/R blades. The DGAC advises of reports of T/R blade tab debonding, and that the loss of the tab leads to a significant increase in the aircraft's vibration level. As a result, the ADs mandate compliance with the manufacturer's service information to install additional rivets on the tabs.
Since we issued the NPRM, Eurocopter France changed its name to Airbus Helicopters. This AD reflects that change and updates the contact information to obtain service information.
Comments
After our NPRM (78 FR 23692, April 22, 2013) was published, we received comments from one commenter.
Request
American Eurocopter Corp.requested that we remove tail rotor blade P/Ns 355A12-0040-14, 355A12-0050-10, and 355A12-0050-12 from the applicability of our AD. The commenter stated that these tail rotor blades have trailing tabs that are integral with the tail rotor blade skin and not bonded on, and therefore are not susceptible to the unsafe condition identified in our AD. We agree and have made the requested change.
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, the DCAG, its technical representative, has notified us of the unsafe condition described in its AD. We are issuing this AD because we evaluated all information provided by the DGAC 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 have changed the applicability from Eurocopter France to Airbus Helicopters and removed tail rotor blades, P/N 355A12-0040-14, 355A12-0050-10, and 355A12-0050- 12, from the Applicability section. These changes are consistent with the intent of the proposals in the NPRM (78 FR 23692, April 22, 2013) and will not increase the economic burden on any operator nor increase the scope of the AD.
Differences Between This AD and the DGAC AD
This AD does not include the Model AS350 BB because it does not have an FAA-issued type certificate. This AD requires compliance within 100 hours time-in-service. The DGAC ADs require compliance within 100 flying hours ``without exceeding 3 months.''
Related Service Information
We reviewed Eurocopter Alert Service Bulletin (ASB) No. 64.00.05, Revision 2, dated February 15, 2007, for Model AS350B, BA, BB, B1, B2, B3, and D helicopters, and ASB No. 64.00.04, Revision 2, dated February 15, 2007, for Model AS355E, F, F1, F2, andN helicopters.
These ASBs specify, within 100 flying hours without exceeding three months, installing additional rivets on T/R blade tabs and inspecting each tab for debonding after the rivets have been installed. The DGAC classified these ASBs as mandatory and issued AD No. F-2004-176 and AD No. F-2004-178 to ensure the continued airworthiness of these helicopters.
Costs of Compliance
We estimate that this AD affects 654 helicopters of U.S. registry and that labor costs average $85 a work-hour. Based on these estimates, we expect the following costs:
Installing rivets and inspecting for tab debonding takes 1 hour for a labor cost of $85. Parts cost $100 for a total cost of $185 per helicopter. The cost for the U.S. fleet totals $120,990.
Replacing the tab with an airworthy tab, if needed, takes 4 hours for a total labor cost of $340. Parts cost $100, for a total cost of $440 per helicopter.
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
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substantial direct effect on the States, on the relationship between the national 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 regulatory action'' 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.