Document Headings

                    Document headings vary by document type but may contain                    the following:                  
                -                       the agency or agencies that issued and signed a document                    
                -                       the number of the CFR title and the number of each part                      the document amends, proposes to amend, or is directly                      related to                    
                -                       the agency docket number / agency internal file number                    
                -                       the RIN which identifies each regulatory action listed in                      the Unified Agenda of Federal Regulatory and Deregulatory                      Actions                    

                    See the                                          Document Drafting Handbook                                        for more details.                  

###### Department of Transportation

###### Federal Aviation Administration

          - 14 CFR Part 39
          - [Docket No. FAA-2021-0095; Project Identifier MCAI-2020-01658-R; Amendment 39-21439; AD 2021-04-17]
          - RIN 2120-AA64

# AGENCY:

Federal Aviation Administration (FAA), DOT.

# ACTION:

Final rule; request for comments.

# SUMMARY:

                        The FAA is adopting a new airworthiness directive (AD) for certain Airbus Helicopters Model AS350B, AS350BA, AS350B1, AS350B2, AS350D, AS355E, AS355F, AS355F1, AS355F2, and AS355N helicopters. This AD was prompted by two reports of debonding of the tail rotor (T/R) blade leading edge protection shields. This AD requires repetitively inspecting certain T/R blades and depending on the inspection results, replacing the T/R blade, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference (IBR). This AD also prohibits installing certain T/R blades. The FAA is issuing                               ( print page 13160)                            this AD to address the unsafe condition on these products.                    

# DATES:

This AD becomes effective March 23, 2021.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of March 23, 2021.

The FAA must receive comments on this AD by April 22, 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 IBR material in this AD, contact the 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 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-2021-0095.                    

## 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-2021-0095; 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 AD, any comments received, and other information. The street address for Docket Operations is listed above. Comments will be available in the AD docket shortly after receipt.                

# FOR FURTHER INFORMATION CONTACT:

                        Kristi Bradley, Aviation Safety Engineer, General Aviation & Rotorcraft Section, International Validation Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email                         *kristin.bradley@faa.gov.*

# SUPPLEMENTARY INFORMATION:

## Discussion

The EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2020-0224R1, dated November 11, 2020 (EASA AD 2020-0224R1), to correct an unsafe condition for all Airbus Helicopters Model AS 350 B, AS 350 BA, AS 350 BB, AS 350 B1, AS350 B2, AS 350 D, AS 355 E, AS 355 F, AS 355 F1, AS 355 F2, and AS 355 N helicopters. EASA AD 2020-0224R1 revises EASA AD 2020-0224-E, dated October 16, 2020, to expand the list of serviceable parts (post-mod 075580).

This AD was prompted by two reports of large debonding of the T/R blade leading edge protection shields. According to EASA, the design and assembly procedure of the affected part (pre-mod 075580) is such that rapid debonding can occur if humidity/liquid water reaches the bonding surface between the leading edge and blade spar. The FAA is issuing this AD to prevent failure of the T/R blade, which could result in loss of tail rotor control and subsequent loss of control of the helicopter. See the EASA AD for additional background information.

## Related IBR Material Under 1 CFR Part 51

EASA AD 2020-0224R1 specifies repetitively visually inspecting each T/R blade leading edge protection shield and repetitively tap inspecting each T/R blade leading edge. EASA AD 2020-0224R1 also prohibits the installation of an affected part and specifies a longer-term modification to replace each affected part with a serviceable part. EASA AD 2020-0224R1 states that replacing all affected parts with serviceable parts on a helicopter constitutes terminating action for the repetitive visual and tap 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.                

## FAA's Determination

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.

## Requirements of This AD

This AD requires accomplishing the actions specified in EASA AD 2020-0224R1, 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.” Additionally, the owner/operator (pilot) may perform the required visual checks but must enter compliance with the applicable paragraph of this AD in the helicopter maintenance records in accordance with 14 CFR 43.9(a)(1) through (4) and 91.417(a)(2)(v). A pilot may perform these checks because they only involve visually checking affected T/R blade leading edge protection shields and bonding strips. This action can be performed equally well by a pilot or a mechanic. This check is an exception to the FAA's standard maintenance regulations.

## Explanation of Required Compliance Information

                    In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA initially worked with Airbus and EASA to develop a process to use certain EASA ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has since coordinated with other manufacturers and civil aviation authorities (CAAs) to use this process. As a result, EASA AD 2020-0224R1 will be incorporated by reference in the FAA final rule. This AD would, therefore, require compliance with EASA AD 2020-0224R1 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 the EASA AD 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 the EASA AD. Service information specified in EASA AD 2020-0224R1 that is required for compliance with EASA AD 2020-0224R1 is available on the internet at                     *https://www.regulations.gov*                     by searching for and locating Docket No. FAA-2021-0095.                

## Differences Between This AD and the EASA AD

                    The EASA AD applies to all Model AS 350 B, AS 350 BA, AS 350 BB, AS                           ( print page 13161)                        350 B1, AS350 B2, AS 350 D, AS 355 E, AS 355 F, AS 355 F1, AS 355 F2, and AS 355 N helicopters, whereas this AD applies to Model AS350B, AS350BA, AS350B1, AS350B2, AS350D, AS355E, AS355F, AS355F1, AS355F2, and AS355N helicopters with certain part-numbered T/R blades installed instead. This AD does not apply to Model AS 350 BB because this model is not FAA type-certificated. The EASA AD requires visually inspecting each T/R blade leading edge protection shield. This AD requires visually checking each T/R blade leading edge protection shield and bonding strip instead and allows a pilot to accomplish these visual checks. The EASA AD requires a longer-term modification of replacing each affected part with a serviceable part, whereas this AD does not. The FAA plans to publish a notice of proposed rulemaking to give the public an opportunity to comment on this longer-term requirement.                

## FAA's Justification and Determination of the Effective Date

Section 553(b)(3)(B) of the Administrative Procedure Act (5 U.S.C.) 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 seeking comment prior to the rulemaking.

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 waiving notice and comment prior to adoption of this rule because the visual repetitive checks must be done before each flight and the initial instance of the repetitive tap inspections must be done within 30 hours time-in-service, a time period of up to about 1.5 months based on the average flight-hour utilization rate of these helicopters. Accordingly, the compliance time for the required actions is shorter than the time necessary for the public to comment and for publication of the final rule. Therefore, notice and opportunity for prior public comment are impracticable and contrary to public interest pursuant to 5 U.S.C. 553(b)(3)(B). In addition, for the reasons stated above, 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.

## Comments Invited

                    The FAA invites you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under                     **ADDRESSES**                    . Include “Docket No. FAA-2021-0095; Project Identifier MCAI-2020-01658-R” at the beginning of your comments. The most helpful comments reference a specific portion of the AD, 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 AD 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 AD.                

## 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 Kristi Bradley, Aviation Safety Engineer, General Aviation & Rotorcraft Section, International Validation Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email                     *kristin.bradley@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.                

## Regulatory Flexibility Act (RFA)

The requirements of the 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 notice and comment, RFA analysis is not required.

## Costs of Compliance

The FAA estimates that this AD affects 450 helicopters of U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the following costs to comply with this AD.

Visually checking the T/R blades takes about 0.25 work-hour for an estimated cost of $21 per helicopter and $9,450 for the U.S. fleet, per inspection cycle. Tap inspecting the T/R blades takes about 0.5 work-hour for an estimated cost of $43 per helicopter and $19,350 for the U.S. fleet, per inspection cycle. Replacing a T/R blade takes about 12 work-hours and parts cost about $10,000 for an estimated cost of $11,020 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

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

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

(2) Will not affect intrastate aviation in Alaska.

      ( print page 13162)    

# 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 

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

**2021-04-17 Airbus Helicopters:**                             Amendment 39-21439; Docket No. FAA-2021-0095; Project Identifier MCAI-2020-01658-R.                        

## (a) Effective Date

This airworthiness directive (AD) becomes effective March 23, 2021.

## (b) Affected ADs

None.

## (c) Applicability

This AD applies to Airbus Helicopters Model AS350B, AS350BA, AS350B1, AS350B2, AS350D, AS355E, AS355F, AS355F1, AS355F2, and AS355N helicopters, certificated in any category, with a tail rotor (T/R) blade part number (P/N) listed in Appendix 1, Table 1, of European Union Aviation Safety Agency (EASA) AD 2020-0224R1, dated November 11, 2020 (EASA AD 2020-0224R1) (pre-mod 075580).

## (d) Subject

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

## (e) Reason

This AD was prompted by two reports of debonding of the T/R blade leading edge protection shields. The FAA is issuing this AD to prevent failure of the T/R blade, which could result in loss of tail rotor control and subsequent loss of 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 2020-0224R1.

## (h) Exceptions to EASA AD EASA AD 2020-0224R1

(1) Where EASA AD 2020-0224R1 refers to flight hours (FH), this AD requires using hours time-in-service.

(2) Where EASA AD 2020-0224R1 refers to October 20, 2020 (the effective date of the original issuance of its AD (EASA AD 2020-0224-E, dated October 16, 2020)) and its effective date, this AD requires using the effective date of this AD.

(3) Where paragraph (1) of EASA AD 2020-0224R1 specifies visually inspecting each T/R blade leading edge protection shield with instructions in the service information, this AD requires visually checking each T/R blade leading edge protection shield and bonding strip for a distortion, dent, and scratch; visually checking the area surrounding each T/R blade leading edge protection along the skin length for a gap; and visually checking the area surrounding the bonding strip for a crack. These visual checks may be performed by the owner/operator (pilot) holding at least a private pilot certificate and must be entered into the aircraft records showing compliance with this AD in accordance with 14 CFR 43.9(a)(1) through (4) and 14 CFR 91.417(a)(2)(v). The record must be maintained as required by 14 CFR 91.417, 121.380, or 135.439.

(4) Where paragraph (5) of EASA AD 2020-0224R1 specifies the modification of replacing each affected part with a serviceable part, this AD does not require this modification.

(5) The “Remarks” section of EASA AD 2020-0224R1 does not apply to this AD.

## (i) Parts Installation Prohibition

As of the effective date of this AD, do not install a T/R blade identified in paragraph (c) of this AD on any helicopter.

## (j) Special Flight Permit

Special flight permits are prohibited if an installed T/R blade does not pass the visual or tap inspections.

## (k) 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 (l)(1) 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.

## (l) Related Information

                            (1) For more information about this AD, contact Kristi Bradley, Aviation Safety Engineer, General Aviation & Rotorcraft Section, International Validation Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email                             *kristin.bradley@faa.gov.*

## (m) 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 2020-0224R1, dated November 11, 2020.

(ii) [Reserved]

                            (3) For EASA AD 2020-0224R1, contact the 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 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-2021-0095.                        

                            (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.*

Issued on February 10, 2021.

Lance T. Gant,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.

[FR Doc. 2021-04803 Filed 3-4-21; 11:15 am]

BILLING CODE 4910-13-P