Discussion
On July 30, 2012, at 77 FR 44509, 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 Model AS332C, L, and L1 helicopters with a certain MRH. That NPRM proposed to require inspecting the MRH bearing for a non-smooth point (friction point), and if there is a friction point in the bearing, then replacing the MRH with an airworthy MRH, or if there is not a friction point in the bearing, then further inspecting the grease expelled from the MRH swash-plate for metal particles. The NPRM also proposed to require that if there is a metal particle in the grease expelled from the MRH swash- plate, replacing the MRH with an airworthy MRH, or if there is not a metal particle in the grease, measuring the force required to rotate the MRH swash-plate and inspecting certain MRH swash-plate assemblies for vertical play in the bearing to determine the airworthiness of the MRH. The proposed requirements were intended to detect deterioration of the MRH bearing and to prevent overloading the scissor links which drive the main rotor system, failure of the scissors links, and subsequent loss of control of the helicopter.
The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, issued EASA Emergency AD No. 2008-0172-E, dated September 9, 2008 (EAD No. 2008- 0172-E), to correct an unsafe condition for the Eurocopter Model AS 332 C, C1, L, and L1 helicopters, with an MRH, part number (P/N) 332A31- 0001-05 or P/N 332A31-0001-06, having a serial number (S/N) of M172, M216, M261, M308, M547, M677, M811, or M936, and having ``logged less than 275 flight hours since the last overhaul or repair.'' EASA states that Eurocopter received a report of deterioration of an MRH bearing on an MRH that was installed on an AS 332 L1 helicopter. The AS 332 L1 helicopter had logged 72 flight hours since the last overhaul. EASA states that there was an onset of vibrations in flight and these vibrations were due to premature deterioration of the upper bearing of the MRH swash-plate. They state that this condition, if not corrected, ``could lead to failure of the scissors links and consequently to the control loss of the helicopter.''
Comments
We gave the public the opportunity to participate in developing this AD, but we did not receive any comments on the NPRM (77 FR 44509, July 30, 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.
Related Service Information
Eurocopter has issued one Emergency Alert Service Bulletin (EASB) with two different numbers, both Revision 0, and both dated September 8, 2008: EASB No. 62.00.73 for Model AS332C, L, and L1 helicopters and non-FAA type certificated Model C1 helicopters; and EASB No. 62.00.30 for non-FAA type certificated Model 532 UC, AC, UL, AL, SC, and UE military helicopters. EASB No. 62.00.73 specifies checking for the absence of a friction point in the MRH bearing. If there is no friction point, EASB No. 62.00.73 specifies checking the condition of the grease in the swash-plate assembly by lubricating the swash-plate, rotating it by hand, and determining if the expelled grease contains traces of metal particles. If the expelled grease does not contain traces of metal particles, EASB No. 62.00.73 specifies checking the swash-plate ``rotationtorque'' using a spring scale. If the rotation torque is less than 5.5 kg, EASB No. 62.00.73 specifies checking the bearing for vertical play. If there is a friction point, the expelled grease contains traces of metal particles, the rotation torque is equal to or greater than 5.5 kg, or there is vertical play in the bearing, EASB No. 62.00.73 specifies removing the MRH and sending it to an approved repair station. EASA classified this EASB as mandatory and issued EAD No. 2008-0172-E to ensure the continued airworthiness of these helicopters.
Differences Between This AD and the EASA AD
The EASA Emergency AD includes Model AS332C1 helicopters. This AD does not include this model helicopter since it is not type certificated in the U.S. The EASA AD does not include S/Ns M561, M859, M935, M938, and M942, whereas this AD does include those S/Ns. The EASA Emergency AD requires operators to comply with the requirements no later than the ``next last flight of the day.'' Our AD requires the actions to be accomplished within 5 hours TIS. Also, the EASA Emergency AD is applicable to the specified helicopters having logged less than 275 flight hours since the last overhaul or repair, whereas our AD only applies to the specified helicopters having less than 275 hours TIS since the last overhaul of the MRH.
Costs of Compliance
We estimate that this AD will affect 6 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD. It will take approximately 1 work-hour per helicopter to accomplish the inspection of the MRH bearing for a friction point, inspection of the swash-plate grease for any metal particles, measurement of the swash-plate force to rotate, and inspection of the bearing for vertical play. It will take approximately 60 work-hours to replace the MRH. These actions will be accomplished at an average labor rate of $85 per work-hour. We estimate the parts cost of replacing an MRH will be approximately $20,000. Based on these figures, we estimate the total cost of this
[[Page 17078]]
AD on U.S. operators is $25,610, assuming that all affected helicopters are inspected and that one MRH in the fleet will need to be replaced.
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 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.
Weprepared 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.