Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Leonardo S.p.a. Model AB139 and Model AW139 helicopters. This proposed AD was prompted by a report that, during a post-flight inspection of an in-service helicopter, a tail rotor slider assembly was found fractured, and the bushing and the actuator rod in the tail rotor servo were partially damaged. This proposed AD would require an inspection of the tail rotor slider assembly for corrosion and signs of circumferential refinishing and, depending on the findings, replacement of the tail rotor slider assembly with a serviceable part or repetitive inspections of the of the tail rotor slider assembly for corrosion and signs of circumferential refinishing, as specified in a European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD, which is proposed for incorporation by reference (IBR). The FAA is proposing this AD to address the unsafe condition on these products.

DATES:

The FAA must receive comments on this proposed AD by August 9, 2021.

ADDRESSES:

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: (202) 493-2251.
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For EASA material that is proposed for IBR in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email ADs@easa.europa.eu; internet www.easa.europa.eu. You may find this IBR material on the EASA website at https://ad.easa.europa.eu. You may view the EASA 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 the EASA material at the FAA, call (817) 222-5110. The EASA material is also available at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0507.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0507; 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 NPRM, the EASA AD, any comments received, and other information. The street address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT:

Andrea Jimenez, Aerospace Engineer, COS Program Management Section, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 1600 Stewart Ave., Suite 410, Westbury, NY 11590; telephone (516) 228-7330; email andrea.jimenez@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2021-0507; Project Identifier 2018-SW-117-AD” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments.

Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https:// ,www.regulations.gov,, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.

Confidential Business Information

CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Andrea Jimenez, Aerospace Engineer, COS Program Management Section, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 1600 Stewart Ave., Suite 410, Westbury, NY 11590; telephone (516) 228-7330; email andrea.jimenez@faa.gov. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2018-0292, dated December 28, 2018 (EASA AD 2018-0292) to correct an unsafe condition for Leonardo S.p.A. (formerly Finmeccanica S.p.A, AgustaWestland S.p.A., Agusta S.p.A.; AgustaWestland Philadelphia Corporation, formerly Agusta Aerospace Corporation) Model AB139 and Model AW139 helicopters, all serial numbers. Although EASA AD 2018-0292 applies to all Model AB139 and Model AW139 helicopters, this proposed AD would apply to helicopters with an affected part installed instead.

This proposed AD was prompted by a report that, during a post-flight inspection of an in-service helicopter, a tail rotor slider assembly was found fractured, and the bushing and the actuator rod in the tail rotor servo were partially damaged. The subsequent investigation revealed that the failure was due to fatigue, initiated from corroded areas (corrosion craters) on the surface of the tail rotor slider assembly characterized by signs of circumferential refinishing. The corrosion craters originated along finishing signs consistent with low grit sanding operations, which can remove the passivation corrosion protection from the tail rotor slider assembly. Sanding is a maintenance activity that is not included in the maintenance manual for Leonardo S.p.a. Model AB139 and AW139 helicopters and is not allowed on in-service helicopters. The FAA is proposing this AD to address corrosion in the tail rotor slider assembly caused by improper refinishing (characterized by signs of circumferential refinishing consistent with sanding). The unsafe condition, if not addressed, could result in fatigue cracks and fracture of the tail rotor slider assembly, resulting in failure of the tail rotor controls and consequent loss of yaw control of the helicopter. See EASA AD 2018-0292 for additional background information.

FAA's Determination and Requirements of This Proposed AD

These helicopters have been approved by EASA and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with the European Union, EASA has notified the FAA about the unsafe condition described in its AD. The FAA is proposing this AD after evaluating all known relevant information and determining that the unsafe condition described previously is likely to exist or develop on other helicopters of these same type designs.

Related Service Information Under 1 CFR Part 51

EASA AD 2018-0292 requires a detailed inspection of the tail rotor slide assembly for corrosion and signs of circumferential refinishing and, depending on the findings, applicable corrective actions. If there is any evidence of corrosion craters the corrective action is replacement of the affected part with a serviceable part. If there is any evidence of surface imperfections caused by circumferential refinishing but no evidence of corrosion, the corrective action is repetitive inspections of the tail rotor slide assembly for corrosion and signs of circumferential refinishing. Replacement of an affected part with a serviceable part is terminating action for the repetitive inspections.

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.

Proposed AD Requirements in This NPRM

This proposed AD would require accomplishing the actions specified in EASA AD 2018-0292, described previously, as incorporated by reference, except for any differences identified as exceptions in the regulatory text of this proposed AD.

Explanation of Required Compliance Information

In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use certain civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, EASA AD 2018-0292 will be incorporated by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2018-0292 in its entirety, through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Using common terms that are the same as the heading of a particular section in EASA AD 2018-0292 does not mean that operators need comply only with that section. For example, where the AD requirement refers to “all required actions and compliance times,” compliance with this AD requirement is not limited to the section titled “Required Action(s) and Compliance Time(s)” in EASA AD 2018-0292. Service information specified in EASA AD 2018-0292 that is required for compliance with it will be available at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0507 after the FAA final rule is published.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 129 helicopters of U.S. Registry. The FAA estimates the following costs to comply with this proposed AD.

The FAA estimates the following costs to do any necessary replacement that would be required based on the results of the proposed inspection. The agency has no way of determining the number of aircraft that might need this replacement:

The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some or all of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators.

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

The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Would not affect intrastate aviation in Alaska, and

(3) Would 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 Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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:

Leonardo S.p.a.: Docket No. FAA-2021-0507; Project Identifier 2018-SW-117-AD.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by August 9, 2021.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Leonardo S.p.a. Model AB139 and AW139 helicopters, certificated in any category, with an affected part as identified in European Aviation Safety Agency (now European Union Safety Agency) (EASA) AD 2018-0292, dated December 28, 2018 (EASA AD 2018-0292).

(d) Subject

Joint Aircraft Service Component (JASC) Code: 6400, Tail Rotor System.

(e) Unsafe Condition

This AD was prompted by a report that, during a post-flight inspection of an in-service helicopter, a tail rotor slider assembly was found fractured, and the bushing and the actuator rod in the tail rotor servo were partially damaged. The FAA is proposing this AD to address corrosion in the tail rotor slider assembly caused by improper refinishing (characterized by signs of circumferential refinishing consistent with sanding). The unsafe condition, if not addressed, could result in fatigue cracks and fracture of the tail rotor slider assembly, resulting in failure of the tail rotor controls and consequent loss of 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, EASA AD 2018-0292.

(h) Exceptions to EASA AD 2018-0292

(1) Where EASA AD 2018-0292 refers to flight hours (FH), this AD requires using hours time-in-service.

(2) Where EASA AD 2018-0292 refers to its effective date, this AD requires using the effective date of this AD.

(3) Where EASA AD 2018-0292 refers to “Part I of the ASB,” this AD requires using “Part I of section 3., Accomplishment Instructions of the ASB,” and where EASA AD 2018-0292 refers to “Part II of the ASB,” this AD requires using “Part II of section 3., Accomplishment Instructions of the ASB.”.

(4) Where the service information referred to in EASA AD 2018-0292 specifies to return certain parts, this AD does not include that requirement.

(5) Where the service information referred to in EASA AD 2018-0292 specifies to contact Leonardo S.p.a. “if in doubt” regarding if a tail rotor slider assembly needs to be replaced based on evidence of corrosion craters, replacement of an affected slider assembly is required by this AD but contacting Leonardo S.p.a. is not required by this AD.

(6) The “Remarks” section of EASA AD 2018-0292 does not apply to this AD.

(i) No Reporting Requirement

Although the service information referenced in EASA AD 2018-0292 specifies to submit certain information to the manufacturer, this AD does not include that requirement.

(j) 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 (k)(2) 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.

(k) Related Information

(1) For EASA AD 2018-0292, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email ADs@easa.europa.eu; internet www.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. This material may be found in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0507.

(2) For more information about this AD, contact Andrea Jimenez, Aerospace Engineer, COS Program Management Section, Operational Safety Branch, Compliance & Airworthiness Division, FAA, 1600 Stewart Ave., Suite 410, Westbury, NY 11590; telephone (516) 228-7330; email andrea.jimenez@faa.gov.