AD 2016-05-06

This AD is effective April 8, 2016.

The Director of the Federal Register approved the incorporation by reference of certain documents listed in this AD as of June 25, 2014 (79 FR 33054, June 10, 2014).

For service information identified in this final rule, contact Airbus Helicopters, Inc., 2701 N. Forum Drive, Grand Prairie, TX 75052; telephone (972) 641-0000 or (800) 232-0323; fax (972) 641-3775; or at http://www.airbushelicopters.com/techpub. You may review the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177.

Robert Grant, Aviation Safety Engineer, Safety Management Group, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email robert.grant@faa.gov.

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to remove AD 2014-07-52, Amendment 39-17858 (79 FR 33054, June 10, 2014) and add a new AD. AD 2014-07-52 applied to Airbus Helicopters Model AS350B, AS350BA, AS350B1, AS350B2, AS350B3, AS350C, AS350D, AS350D1, AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters with Modification (MOD) 07 3215 or with a reinforcement angle part number (P/N) 350A08.2493.21 or P/N 350A08.2493.23 installed. AD 2014-07-52 required, for helicopters with 640 or more hours TIS, repetitively inspecting each reinforcement angle for a crack every 10 hours TIS. As an optional action, AD 2014-07-52 allowed a repetitive 165 hour TIS inspection of the reinforcement angle under each attaching screw for a crack. AD 2014-07-52 was prompted by Emergency AD No. 2014-0076-E, dated March 25, 2014, issued by EASA, which is the Technical Agent for the Member States of the European Union. EASA advises that during the inspection of several AS355 helicopters, cracks found in the reinforcement angles had initiated on the non-visible surface of the angle, and that this condition, if not corrected, could lead to further crack propagation and subsequent loss of the tailboom, resulting in loss of control of the helicopter. The EASA AD requires repetitive inspections of the reinforcement angles, and states that a terminating action is under investigation.

The NPRM published in the Federal Register on July 23, 2015 (80 FR 43645). The NPRM proposed to retain the 10 hour TIS repetitive inspections of the reinforcement angle and require (instead of allow as an option) the 165 hour TIS inspection of the junction frame bores as terminating action for the 10 hour TIS inspections. The NPRM also proposed to revise the applicability to only include helicopters with reinforcement angle P/N 350A08.2493.21 and P/N 350A08.2493.23, and not include helicopters with MOD 07 3215. Since MOD 07 3215 installed reinforcement angle P/N 350A08.2493.21 and P/N 350A08.2493.23, AD 2014-07-52 was written to apply to helicopters with either the reinforcement angle P/Ns or with MOD 07 3215, so that operators could more easily determine whether AD 2014-07-52 applied to their aircraft. Airbus Helicopters then developed MOD 07 3232, which removes reinforcement angle P/N 350A08.2493.21 and P/N 350A08.2493.23. We removed MOD 07 3215 from the applicability because we did not want the AD to apply to a helicopter with both MOD 07 3215 and MOD 07 3232 in its aircraft records, as it would not have reinforcement angle P/N 350A08.2493.21 or P/N 350A08.2493.23 installed. The proposed requirements were intended to detect a crack in the reinforcement angle, which if not corrected, could result in loss of the tailboom and subsequent loss of control of the helicopter.

Since the NPRM was issued, a group email address has been established for requesting an FAA alternative method of compliance for a helicopter of foreign design. We have revised this contact information in this final rule to reflect the new email address.

We gave the public the opportunity to participate in developing this AD, but we did not receive any comments on the NPRM (79 FR 33054, June 10, 2014).

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.

We consider this AD to be an interim action. If final action is later identified, we might consider further rulemaking then.

This AD is not applicable to the AS350BB as that model is not type certificated in the U.S. This AD applies to Airbus Helicopters Model AS350C and AS350D1 helicopters because these helicopters have a similar design. Finally, the EASA AD requires operators to contact Airbus Helicopters if there is a crack, and this AD does not, however it does require repairing the crack before further flight.

Airbus Helicopters issued Emergency Alert Service Bulletin (EASB) No. 05.00.70 for Model AS350B, BA, BB, Bl, B2, B3, and D helicopters, and EASB No. 05.00.62 for Model AS355E, F, F1, F2, N, and NP helicopters, both Revision 0 and dated March 24, 2014. EASB No. 05.00.70 and EASB No. 05.00.62 describe procedures for inspecting the angle reinforcements for a crack. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We estimate that this AD affects 822 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD. At an average labor rate of $85 per work-hour, inspecting the reinforcement angles for a crack without removing the screws requires 1.0 work-hour, for a cost per helicopter of $85 and a total cost of $69,870 for the U.S. fleet, per inspection cycle. Removing the screws and inspecting the reinforcement angle requires 2 work-hours, for a cost per helicopter of $170 and a total cost of $139,740 for the U.S. fleet, per inspection cycle. If required, repairing a cracked reinforcement angle requires about 10 work-hours, and required parts cost about $300, for a total cost per helicopter of $1,150.

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.

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.

We prepared an economic evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2014-07-52, Amendment 39-17858 (79 FR 33054, June 10, 2014), and adding the following new AD: