Airworthiness Directives; Airbus Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1 helicopters. This AD was prompted by a report of a yaw control failure that was the result of the disconnection of the tail rotor hub (TRH) pitch control rod from the tail rotor servo-control, which resulted from a seized TRH bearing. The TRH bearing had grease dissolving after contamination by leaked hydraulic fluid from the tail rotor servo-control that came through the TRH assembly boot. This AD requires repetitive inspections for hydraulic leaks, corrective actions if necessary, and an optional modification which constitutes terminating action, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective August 11, 2021.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of August 11, 2021.

ADDRESSES:

For material incorporated by reference (IBR) in this AD, contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: ADs@easa.europa.eu; internet: www.easa.europa.eu. You may find this material on the EASA website at https://ad.easa.europa.eu. You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call 817-222-5110. It is also available in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0333.

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0333; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Hal Jensen, Aerospace Engineer, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 950 L'Enfant Plaza N SW, Washington, DC 20024; phone: (202) 267-9167; email: hal.jensen@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2020-0021, dated February 6, 2020 (EASA AD 2020-0021) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for all Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1 helicopters. Although EASA AD 2020-0021 applies to all Model AS332C, AS332C1, AS332L, and AS332L1 helicopters, this AD applies to helicopters with an affected part installed instead.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1 helicopters. The NPRM published in the Federal Register on April 22, 2021 (86 FR 21238). The NPRM was prompted by a report of a yaw control failure that was the result of the disconnection of the TRH pitch control rod from the tail rotor servo-control, which resulted from a seized TRH bearing. The TRH bearing had grease dissolving after contamination by leaked hydraulic fluid from the tail rotor servo-control that came through the TRH assembly boot. The NPRM proposed to require repetitive inspections for hydraulic leaks, corrective actions if necessary, and an optional modification which constitutes terminating action, as specified in an EASA AD.

The FAA is issuing this AD to address seized TRH bearings, which could reduce the effectiveness of the pitch control of the tail rotor system, possibly resulting in reduced yaw control of the helicopter. See the MCAI for additional background information.

Discussion of Final Airworthiness Directive

Comments

The FAA gave the public the opportunity to participate in developing this final rule. The FAA received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

The FAA reviewed the relevant data and determined that air safety and the public interest require adopting this final rule as proposed, except for minor editorial changes. The FAA has determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for addressing the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

EASA AD 2020-0021 describes procedures for repetitive inspections for hydraulic leaks, corrective actions if necessary (i.e., replacement of the pitch control rod bearing of the affected TRH assembly), and an optional modification (i.e., installation of a TRH assembly having certain part numbers) which constitutes terminating action. This material 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.

Costs of Compliance

The FAA estimates that this AD affects 10 helicopters of U.S. registry. The FAA estimates the following costs to comply with this AD:

The FAA estimates the following costs to do any necessary on-condition actions that would be required based on the results of any required actions. The FAA has no way of determining the number of helicopters that might need these on-condition actions:

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.

The FAA is 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 products 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) Will not affect intrastate aviation in Alaska, and

(3) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Amendment

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

PART 39—AIRWORTHINESS DIRECTIVES

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

Authority: 49 U.S.C. 106(g), 40113, 44701.

2. The FAA amends § 39.13 by adding the following new airworthiness directive:

2021-13-04 Airbus Helicopters: Amendment 39-21609; Docket No. FAA-2021-0333; Project Identifier MCAI-2020-00252-R.

(a) Effective Date

This airworthiness directive (AD) is effective August 11, 2021.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Airbus Helicopters Model AS332C, AS332C1, AS332L, and AS332L1 helicopters, certificated in any category, with a tail rotor hub (TRH) assembly, having part number (P/N) 332A33-0001-05 or P/N 332A33-0001-06, installed.

(d) Subject

Joint Aircraft System Component (JASC) Code 6420, Tail rotor head.

(e) Reason

This AD was prompted by a report of a yaw control failure that was the result of a disconnection of the TRH pitch control rod from the tail rotor servo-control, which resulted from a seized TRH bearing. The TRH bearing had grease dissolving after contamination by leaked hydraulic fluid from the tail rotor servo-control that came through the TRH assembly boot. The FAA is issuing this AD to address seized TRH bearings, which could reduce the effectiveness of the pitch control of the tail rotor system, possibly resulting in reduced yaw control of the helicopter.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Requirements

Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) AD 2020-0021, dated February 6, 2020 (EASA AD 2020-0021).

(h) Exceptions to EASA AD 2020-0021

(1) Where EASA AD 2020-0021 refers to its effective date, this AD requires using the effective date of this AD.

(2) The “Remarks” section of EASA AD 2020-0021 does not apply to this AD.

(3) Where EASA AD 2020-0021 refers to flight hours (FH), this AD requires using hours time-in-service.

(4) Where paragraph (1) of EASA AD 2020-0021 requires doing inspections “in accordance with the instructions of the ASB [alert service bulletin],” this AD requires accomplishing a visual inspection for any hydraulic fluid leak at the TRH boot.

(5) Where EASA AD 2020-0021 refers to February 28, 2004 (the effective date of Direction Générale de l'Aviation Civile (DGAC) AD F-2004-031, dated February 18, 2004), this AD requires using the effective date of this AD.

(i) Alternative Methods of Compliance (AMOCs)

(1) The Manager, International Validation Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD. Information may be emailed to: 9-AVS-AIR-730-AMOC@faa.gov.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(j) Related Information

For more information about this AD, contact Hal Jensen, Aerospace Engineer, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 950 L'Enfant Plaza N SW, Washington, DC 20024; phone: (202) 267-9167; email: hal.jensen@faa.gov.

(k) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise.

(i) European Union Aviation Safety Agency (EASA) AD 2020-0021, dated February 6, 2020.

(ii) [Reserved]

(3) For EASA AD 2020-0021, contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: ADs@easa.europa.eu; internet: www.easa.europa.eu . You may find this material on the EASA website at https://ad.easa.europa.eu . You may find this EASA AD on the EASA website at https://ad.easa.europa.eu .

(4) You may view this service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call 817-222-5110. This material may be found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0333.

(5) You may view this material that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email fedreg.legal@nara.gov, or go to https://www.archives.gov/federal-register/cfr/ibr-locations.html .