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###### Department of Transportation

###### Federal Aviation Administration

          - 14 CFR Part 39
          - [Docket No. FAA-2021-0508; Project Identifier MCAI-2021-00070-T]
          - RIN 2120-AA64

# AGENCY:

Federal Aviation Administration (FAA), DOT.

# ACTION:

Notice of proposed rulemaking (NPRM).

# SUMMARY:

The FAA proposes to supersede Airworthiness Directive (AD) 2021-03-03, which applies to certain ATR-GIE Avions de Transport Régional Model ATR72 airplanes. AD 2021-03-03 requires revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. Since the FAA issued AD 2021-03-03, the FAA has determined that new or more restrictive airworthiness limitations are necessary. This proposed AD would require revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations, as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference. 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 September 3, 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 material that will be incorporated by reference (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 this IBR material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available in the AD docket on the internet at                         *https://www.regulations.gov*                         by searching for and locating Docket No. FAA-2021-0508.                    

## 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-2021-0508; 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, any comments received, and other information. The street address for Docket Operations is listed above.                

# FOR FURTHER INFORMATION CONTACT:

                        Shahram Daneshmandi, Aerospace Engineer, Large Aircraft Section, International Validation Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone and fax 206-231-3220; email                         *shahram.daneshmandi@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-2021-0508; Project Identifier MCAI-2021-00070-T” 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 the 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 proposed 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 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 Shahram Daneshmandi, Aerospace Engineer, Large Aircraft Section, International Validation Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone and fax 206-231-3220; email                     *shahram.daneshmandi@faa.gov.*                     Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.                

## Background

                    The FAA issued AD 2021-03-03, Amendment 39-21406 (86 FR 11103, February 24, 2021) (AD 2021-03-03), for certain ATR-GIE Avions de Transport Régional Model ATR72 airplanes. AD 2021-03-03 requires revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. The FAA issued AD 2021-03-03 to address fatigue cracking and damage in principal structural elements, which                           ( print page 38240)                        could result in reduced structural integrity of the airplane.                

## Actions Since AD 2021-03-03 Was Issued

Since the FAA issued AD 2021-03-03, the FAA has determined that new or more restrictive airworthiness limitations are necessary.

EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2021-0020, dated January 15, 2021 (EASA AD 2021-0020) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for all ATR-GIE Avions de Transport Régional Model ATR72 airplanes. EASA AD 2020-0020 refers to ATR ATR72 Time Limits Document. Revision 18, dated October 9, 2020. Airplanes with an original airworthiness certificate or original export certificate of airworthiness issued after October 9, 2020, must comply with the airworthiness limitations specified as part of the approved type design and referenced on the type certificate data sheet; this AD therefore does not include those airplanes in the applicability.

This proposed AD was prompted by a determination that new or more restrictive airworthiness limitations are necessary. The FAA is proposing this AD to address fatigue cracking and damage in principal structural elements, which could result in reduced structural integrity of the airplane. See the MCAI for additional background information.

## Related Service Information Under 1 CFR Part 51

EASA AD 2021-0020 describes new or more restrictive airworthiness limitations for airplane structures and safe life limits.

                    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 and Requirements of This Proposed AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to the FAA's bilateral agreement with the State of Design Authority, the FAA has been notified of the unsafe condition described in the MCAI referenced above. The FAA is proposing this AD because the FAA evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design.

## Proposed AD Requirements

This proposed AD would retain all of the requirements of AD 2021-03-03. This proposed AD would also require revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations, which are specified in EASA AD 2021-0020 described previously, as incorporated by reference. Any differences with EASA AD 2021-0020 are identified as exceptions in the regulatory text of this AD.

                    This proposed AD would require revisions to certain operator maintenance documents to include new actions (                    *e.g.,*                     inspections). Compliance with these actions is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by this proposed AD, the operator may not be able to accomplish the actions described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance according to paragraph (m)(1) 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 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 2021-0020 will be incorporated by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2021-0020 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 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 2021-0020 that is required for compliance with EASA AD 2021-0020 will be available on the internet at                     *https://www.regulations.gov*                     by searching for and locating Docket No. FAA-2021-0508 after the FAA final rule is published.                

## Airworthiness Limitation ADs Using the New Process

The FAA's process of incorporating by reference MCAI ADs as the primary source of information for compliance with corresponding FAA ADs has been limited to certain MCAI ADs (primarily those with service bulletins as the primary source of information for accomplishing the actions required by the FAA AD). However, the FAA is now expanding the process to include MCAI ADs that require a change to airworthiness limitation documents, such as airworthiness limitation sections.

For these ADs that incorporate by reference an MCAI AD that changes airworthiness limitations, the FAA requirements are unchanged. Operators must revise the existing maintenance or inspection program, as applicable, to incorporate the information specified in the new airworthiness limitation document. The airworthiness limitations must be followed according to 14 CFR 91.403(c) and 91.409(e).

                    The previous format of the airworthiness limitation ADs included a paragraph that specified that no alternative actions (                    *e.g.,*                     inspections) or intervals may be used unless the actions and intervals are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in the AMOCs paragraph under “Other FAA Provisions.” This new format includes a “New Provisions for Alternative Actions and Intervals” paragraph that does not specifically refer to AMOCs, but operators may still request an AMOC to use an alternative action or interval.                

## Costs of Compliance

The FAA estimates that this proposed AD affects 23 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:

The FAA estimates the total cost per operator for the retained actions from AD 2021-03-03 to be $7,650 (90 work-hours × $85 per work-hour).

                    The FAA has determined that revising the existing maintenance or inspection program takes an average of 90 work-hours per operator, although the agency recognizes that this number may vary from operator to operator. Since operators incorporate maintenance or inspection program changes for their affected fleet(s), the FAA has determined that a per-operator estimate is more accurate than a per-airplane estimate.                          ( print page 38241)    

The FAA estimates the total cost per operator for the new proposed actions to be $7,650 (90 work-hours × $85 per work-hour).

## 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.

§ 39.13 

2. The FAA amends § 39.13 by 

a. Removing Airworthiness Directive (AD) 2021-03-03, Amendment 39-21406 ( 86 FR 11103, February 24, 2021), and

b. Adding the following new AD: 

**ATR-GIE Avions de Transport Régional:**                         Docket No. FAA-2021-0508; Project Identifier MCAI-2021-00070-T.                    

## (a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by September 3, 2021.

## (b) Affected ADs

This AD replaces AD 2021-03-03, Amendment 39-21406 (86 FR 11103, February 24, 2021) (AD 2021-03-03).

## (c) Applicability

This AD applies to ATR-GIE Avions de Transport Régional Model ATR72-101, -102, -201, -202, -211, -212, and -212A airplanes, certificated in any category, with an original airworthiness certificate or original export certificate of airworthiness issued on or before October 9, 2020.

## (d) Subject

Air Transport Association (ATA) of America Code 05, Time Limits/Maintenance Checks.

## (e) Reason

This AD was prompted by a determination that new or more restrictive airworthiness limitations are necessary. The FAA is issuing this AD to address fatigue cracking and damage in principal structural elements, which could result in reduced structural integrity of the airplane.

## (f) Compliance

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

## (g) Retained Maintenance or Inspection Program Revision, With No Changes

This paragraph restates the requirements of paragraph (k) of AD 2021-03-03, with no changes. For airplanes with an original airworthiness certificate or original export certificate of airworthiness issued on or before December 12, 2019, 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 2020-0173, dated August 5, 2020 (EASA AD 2020-0173). Accomplishing the maintenance or inspection program revision required by paragraph (j) of this AD terminates the requirements of this paragraph.

## (h) Retained Exceptions to EASA AD 2020-0173, With Revised Exceptions

This paragraph restates the requirements of paragraph (l) of AD 2021-03-03, with revised exceptions.

(1) Where EASA AD 2020-0173 refers to its effective date, this AD requires using March 31, 2021 (the effective date of AD 2021-03-03).

(2) The requirements specified in paragraphs (1) and (3) of EASA AD 2020-0173 do not apply to this AD.

(3) Paragraph (4) of EASA AD 2020-0173 specifies revising “the approved AMP [aircraft maintenance program]” within 12 months after its effective date, but this AD requires revising the existing maintenance or inspection program, as applicable, to incorporate the “limitations, tasks and associated thresholds and intervals” specified in paragraph (4) of EASA AD 2020-0173 within 90 days after March 31, 2021 (the effective date of AD 2021-03-03).

(4) Except as provided by paragraph (2) of EASA AD 2020-0173, the initial compliance time for doing the tasks specified in paragraph (4) of EASA AD 2020-0173 is at the applicable “associated thresholds” specified in paragraph (4) of EASA AD 2020-0173, or within 90 days after March 31, 2021 (the effective date of AD 2021-03-03), whichever occurs later.

(5) The provisions specified in paragraphs (5) and (6) of EASA AD 2020-0173 do not apply to this AD.

(6) The “Remarks” section of EASA AD 2020-0173 does not apply to this AD.

## (i) Retained Restrictions on Alternative Actions and Intervals, With a New Exception

                        This paragraph restates the requirements of paragraph (m) of AD 2021-03-03, with a new exception. Except as required by paragraph (j) of this AD, after the maintenance or inspection program has been revised as required by paragraph (g) of this AD, no alternative actions (                        *e.g.,*                         inspections) or intervals, are allowed unless they are approved as specified in the provisions of the “Ref. Publications” section of EASA AD 2020-0173.                    

## (j) New Maintenance Program Revision

Except as specified in paragraph (k) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, EASA AD 2021-0020, dated January 15, 2021 (EASA AD 2021-0020). Accomplishing the maintenance or inspection program revision required by this paragraph terminates the requirements of paragraph (g) of this AD.

## (k) Exceptions to EASA AD 2021-0020

(1) Where EASA AD 2021-0020 refers to its effective date, this AD requires using the effective date of this AD.

(2) The requirements specified in paragraphs (1) and (2) of EASA AD 2021-0020 do not apply to this AD.

(3) Paragraph (3) of EASA AD 2021-0020 specifies revising “the approved AMP” within 12 months after its effective date, but this AD requires revising the existing maintenance or inspection program, as applicable, within 90 days after the effective date of this AD.

                        (4) Except as provided by Note 1 of EASA AD 2021-0020, the initial compliance time for doing the tasks specified in paragraph (3) of EASA AD 2021-0020 is at the applicable “thresholds” as incorporated by the requirements of paragraph (3) of EASA AD 2021-0020, or within 90 days after the                               ( print page 38242)                            effective date of this AD, whichever occurs later.                    

(5) The provisions specified in paragraphs (4) and (5) of EASA AD 2021-0020 do not apply to this AD.

(6) The “Remarks” section of EASA AD 2021-0020 does not apply to this AD.

## (l) New Provisions for Alternative Actions and Intervals

                        After the maintenance or inspection program has been revised as required by paragraph (j) of this AD, no alternative actions (                        *e.g.,*                         inspections) and intervals are allowed unless they are approved as specified in the provisions of the “Ref. Publications” section of EASA AD 2021-0020.                    

## (m) Other FAA AD Provisions

The following provisions also apply to this AD:

                        (1)                         *Alternative Methods of Compliance (AMOCs):*                         The Manager, Large Aircraft Section, 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 Large Aircraft Section, International Validation Branch, send it to the attention of the person identified in paragraph (n)(2) of this AD. Information may be emailed to:                         *9-AVS-AIR-730-AMOC@faa.gov.*                         Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office.                    

                        (2)                         *Contacting the Manufacturer:*                         For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, Large Aircraft Section, International Validation Branch, FAA; or EASA; or ATR-GIE Avions de Transport Régional's EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.                    

## (n) Related Information

                        (1) For information about EASA AD 2021-0020, 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 EASA AD on the EASA website at                         *https://ad.easa.europa.eu.*                         You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. 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-2021-0508.                    

                        (2) For more information about this AD, contact Shahram Daneshmandi, Aerospace Engineer, Large Aircraft Section, International Validation Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; telephone and fax 206-231-3220; email                         *shahram.daneshmandi@faa.gov.*

Issued on June 17, 2021.

Gaetano A. Sciortino,

Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service.

[FR Doc. 2021-15333 Filed 7-19-21; 8:45 am]

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