2024-04589. Airworthiness Directives; Airbus Helicopters Deutschland GmbH (AHD) Helicopters

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, EC135T2, EC135T3, and EC635T2+ helicopters. This AD was prompted by a report of a separated tail rotor (T/R) blade due to a crack which was caused by intergranular corrosion. This AD requires repetitively inspecting certain part-numbered T/R blades for a crack and, depending on the results, removing any cracked T/R blade from service. This AD also prohibits installing certain T/R blades on any helicopter unless certain requirements are met. These actions are specified in a European Union Aviation Safety Agency (EASA) emergency 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 March 19, 2024.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of March 19, 2024.

The FAA must receive comments on this AD by April 18, 2024.

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 regulations.gov. Follow the instructions for submitting comments.

• Fax: [phone].

• 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.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA–2024–0453; 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, the EASA emergency AD, any comments received, and other information. The street address for Docket Operations is listed above.

Material Incorporated by Reference:

• For EASA material identified in this final rule, contact Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; website easa.europa.eu. You may find the EASA material on the EASA website ad.easa.europa.eu.

• You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N–321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222–5110. The EASA material is also available at regulations.gov under Docket No. FAA–2024–0453.

Other Related Service Information: For Airbus Helicopters service information identified in this final rule, contact Airbus Helicopters, 2701 North Forum Drive, Grand Prairie, TX 75052; phone [phone] or (800) 232–0323; fax [phone]; or at airbus.com/en/products-services/helicopters/hcare-services/airbusworld. You may also view this service information at the FAA contact information under Material Incorporated by Reference above.

FOR FURTHER INFORMATION CONTACT:

Dan McCully, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail].

Comments Invited

The FAA invites you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under ADDRESSES . Include “Docket No. FAA–2024–0453; Project Identifier MCAI–2024–00068–R” at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, 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 final rule 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 regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule.

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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Dan McCully, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail]. Any commentary that the FAA receives which 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 Emergency AD 2024–0028–E, dated January 25, 2024 (EASA AD 2024–0028–E), to correct an unsafe condition on Airbus Helicopters Deutschland GmbH Model EC135 P1, EC135 P2, EC135 P2+, EC135 P3, EC135 T1, EC135 T2, EC135 T2+, EC135 T3, EC635 P2+, EC635 P3, EC635 T1, EC635 T2+, and EC635 T3 helicopters.

This AD was prompted by a report of increased vibrations of the T/R which was the result of a separated T/R blade due to a crack on the T/R assembly. Further investigation determined that the affected parts can be subject to intergranular corrosion, possibly leading to cracks. The FAA is issuing this AD to detect and address cracks in the affected T/R blades. The unsafe condition, if not addressed, could result in separation of a T/R blade assembly and subsequent reduced control of the helicopter.

You may examine the EASA AD in the AD docket at regulations.gov under Docket No. FAA–2024–0453.

Related Service Information Under 1 CFR Part 51

The FAA reviewed EASA AD 2024–0028–E, which specifies procedures for repetitively inspecting affected T/R blades for a crack and if a crack is detected, replacing the affected T/R blade with a serviceable part as defined in EASA AD 2024–0028–E. EASA AD 2024–0028–E also specifies that installing an affected part is allowed provided that it is a serviceable part as defined in EASA AD 2024–0028–E. Lastly, EASA AD 2024–0028–E also specifies that replacing an affected T/R blade assembly with an eligible T/R blade assembly that is not an affected part constitutes terminating action for certain 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 ADDRESSES .

Other Related Service Information

The FAA also reviewed Airbus Helicopters Emergency Alert Service Bulletin No. EC135–64–11–0001, Issue 001, dated January 25, 2024. This service information specifies procedures for inspecting the T/R blade for any crack and replacing the T/R blade if necessary. This service information also specifies sending an affected T/R blade along with certain information to Airbus Helicopters.

FAA's Determination

These products have been approved by the aviation authority of another country and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the EASA emergency AD referenced above. The FAA is issuing this AD after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type designs.

AD Requirements

This AD requires accomplishing the actions specified in EASA AD 2024–0028–E, described previously, as incorporated by reference, except for any differences identified as exceptions in the regulatory text of this AD and except as discussed under “Differences Between this AD and the EASA 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 some 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 2024–0028–E is incorporated by reference in this FAA final rule. This AD, therefore, requires compliance with EASA AD 2024–0028–E in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this AD. Using common terms that are the same as the heading of a particular section in EASA AD 2024–0028–E 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 2024–0028–E. Service information referenced in EASA AD 2024–0028–E for compliance will be available at regulations.gov under Docket No. FAA–2024–0453 after this final rule is published.

Differences Between This AD and the EASA AD

EASA AD 2024–0028–E applies to Airbus Helicopters Model EC635 P2+, EC635 P3, EC635 T1, and EC635 T3 helicopters, whereas this AD does not because these models are not FAA type-certificated.

The service information referenced in EASA AD 2024–0028–E specifies inspecting for cracks by performing either a dye-penetrant inspection, eddy current inspection, or fluorescent penetrant inspection, whereas this AD does not. Instead, this AD requires inspecting for cracks using a fluorescent penetrant inspection or eddy current inspection, performed by a Level II or Level III inspector certified in the FAA-acceptable standards for nondestructive inspection personnel.

Where the service information referenced in EASA AD 2024–0028–E specifies reporting certain information and returning an unserviceable part to Airbus Helicopter, this AD does not require these actions.

Interim Action

The FAA considers that this AD is an interim action. If final action is later identified, the FAA might consider further rulemaking then.

Justification for Immediate Adoption and Determination of the Effective Date

Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq.) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause.

An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because each T/R blade is critical to the control of a helicopter and the FAA also has no information pertaining to how quickly a cracked T/R blade may propagate to failure. Additionally, affected T/R blades are installed on high usage helicopters, which could increase the likeliness of occurrence of a failure. In light of this, the initial action required by this AD must be accomplished before further flight or within 10 hours time-in-service for some helicopters, which is shorter than the time necessary for the public to comment and for publication of the final rule. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b)(3)(B).

In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment.

Regulatory Flexibility Act

The requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without prior notice and comment, RFA analysis is not required.

Costs of Compliance

The FAA estimates that this AD affects 363 helicopters of U.S. registry. Labor costs are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the following costs to comply with this AD.

Inspecting an affected T/R blade assembly for any crack takes up to 3 work-hours and parts cost approximately $50 for an estimated cost of up to $3,050 per helicopter (there may be up to 10 affected T/R blades per helicopter) and up to $1,107,150 for the U.S. fleet, per inspection cycle. Replacing a T/R blade takes approximately 3 work-hours and parts cost approximately $4,900 for an estimated cost of $5,155 per T/R blade.

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, and

(2) Will not affect intrastate aviation in Alaska.

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.

§ 39.13

[Amended]

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

2024–04–10 Airbus Helicopters Deutschland GmbH (AHD): Amendment 39–22689; Docket No. FAA–2024–0453; Project Identifier MCAI–2024–00068–R.

(a) Effective Date

This airworthiness directive (AD) is effective March 19, 2024.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, EC135T2, EC135T3, and EC635T2+ helicopters, certificated in any category.

(d) Subject

Joint Aircraft System Component (JASC) Code: 6410, Tail Rotor Blades.

(e) Unsafe Condition

This AD was prompted by a report of a separated tail rotor (T/R) blade due to a crack which was caused by intergranular corrosion. The FAA is issuing this AD to detect and address cracks in affected T/R blades. The unsafe condition, if not addressed, could result in separation of a T/R blade assembly and subsequent reduced control of the helicopter.

(f) Compliance

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

(g) Requirements

Except as specified in paragraphs (h) and (i) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) Emergency AD 2024–0028–E, dated January 25, 2024 (EASA AD 2024–0028–E).

(h) Exceptions to EASA AD 2024–0028–E

(1) Where EASA AD 2024–0028–E states “flight hours (FH)” and “FH;” for this AD, replace that text with “hours time-in-service (TIS).”

(2) Where EASA AD 2024–0028–E refers to its effective date, this AD requires using the effective date of this AD.

(3) Where paragraph (1) of EASA AD 2024–0028–E states “Before an affected part exceeds 685 FH since first installation on a helicopter, or within 10 FH after the effective date of this AD, whichever occurs later;” for this AD, replace that text with “Before an affected part, as defined in EASA AD 2024–0028–E, accumulates 685 total hours TIS, or within 10 hours TIS after the effective date of this AD, whichever occurs later, and if the total hours TIS accumulated on an affected part, as defined in EASA AD 2024–0028–E, is unknown, before further flight after the effective date of this AD.”

(4) Where paragraph (2) of EASA AD 2024–0028–E states “following the installation of an affected part, having accumulated 685 FH or more since first installation on a helicopter, inspect that affected part in accordance with the instructions of the ASB within the interval as defined in Table 2 of this AD, as applicable. Thereafter, that affected part must be inspected as required by paragraph (1) of this AD;” for this AD, replace that text with “do not install an affected part, as defined in EASA AD 2024–0028–E, unless that affected part has been inspected in accordance with the instructions of the ASB as specified in paragraph (h)(4)(i) or (ii) of this AD, as applicable.

(i) For an affected part that has accumulated 685 or more total hours TIS since first installation on any helicopter, before further flight after the effective date of this AD, inspect that affected part unless already done within the interval as defined in Table 2 of EASA AD 2024–0028–E, as applicable, and thereafter inspect that affected part within the interval as defined in Table 1 of EASA AD 2024–0028–E, as applicable.

(ii) For an affected part that has accumulated an unknown number of total hours TIS, before further flight after the effective date of this AD, inspect that affected part and thereafter inspect that affected part within the interval as defined in Table 1 of EASA AD 2024–0028–E, as applicable.”

(5) Instead of complying with paragraph (3) of EASA AD 2024–0028–E, for this AD, comply with the following: “As a result of an inspection required by paragraphs (1) or (2) of EASA AD 2024–0028–E, if there is a crack, before further flight, remove the affected part, as defined in EASA AD 2024–0028–E, from service and replace it with a serviceable part, as defined in EASA AD 2024–0028–E, by following the instructions of the ASB.”

(6) Where the service information referenced in EASA AD 2024–0028–E specifies “Examine the TRB (1) within the AFFECTED AREA (2) for cracks with one of the following methods;” for this AD, replace that text with “Examine the TRB (1) within the AFFECTED AREA (2) for any crack by following Method C or Method D.”

Note 1 to paragraph (h)(6): This note applies to paragraphs (h)(6) and (7) of this AD. Advisory Circular 65–31B contains examples of FAA-acceptable Level II and Level III qualification standards criteria for inspection personnel doing nondestructive test inspections.

(7) Where the service information referenced in EASA AD 2024–0028–E specifies performing an eddy current inspection or a fluorescent penetrant inspection (FPI), this AD requires an eddy current inspection or FPI performed by a Level II or Level III inspector certified in the FAA-acceptable standards for nondestructive inspection personnel.

(8) This AD does not adopt the “Remarks” section of EASA AD 2024–0028–E.

(i) No Reporting or Return of Parts

Although the service information referenced in EASA AD 2024–0028–E specifies to submit certain information and send removed parts to the manufacturer, this AD does not include those actions.

(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) of this AD. Information may be emailed to: [e-mail].

(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

For more information about this AD, contact Dan McCully, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail].

(l) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference 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 the AD specifies otherwise.

(i) European Union Aviation Safety Agency (EASA) Emergency AD 2024–0028–E, dated January 25, 2024.

(ii) [Reserved]

(3) For EASA AD 2024–0028–E, contact Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone [phone]; email [e-mail]; website easa.europa.eu. You may find the EASA material on the EASA website ad.easa.europa.eu.

(4) You may view this service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N–321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222–5110.

(5) You may view this service information at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/​federal-register/​cfr/​ibr-locations or email [e-mail].

Issued on February 23, 2024.

Caitlin Locke,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.