Document ID: FAA-2021-0317-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Airbus Helicopters Deutschland GmbH Helicopters
Posted Date: 2021-04-23T04:00Z

[Federal Register Volume 86, Number 77 (Friday, April 23, 2021)]
[Rules and Regulations]
[Pages 21641-21645]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-08574]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0317; Project Identifier MCAI-2021-00175-R; 
Amendment 39-21520; AD 2021-09-07]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters Deutschland GmbH 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2019-17-
02, which applied to certain Airbus Helicopters Deutschland GmbH 
(Airbus Helicopters) Model EC135P1, EC135P2, EC135P2+, EC135P3, 
EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters. AD 2019-17-02 
required inspecting certain part-numbered actuators for corrosion, 
removing them as necessary, and reporting certain information. This new 
AD continues to require inspecting certain part-numbered actuators, 
removing them as necessary, and reporting; and extends the compliance 
time for the initial inspection, expands the applicability, and 
includes new requirements for repetitive replacement of affected 
actuators; as specified in a European Union Aviation Safety Agency 
(EASA) AD, which is incorporated by reference. This AD was prompted by 
a hard landing of a helicopter and the discovery of a ruptured and 
displaced tie bar inside the piston of the longitudinal single-axis 
actuator of the main rotor actuator (MRA). The FAA is issuing this AD 
to address the unsafe condition on these products.

DATES: This AD becomes effective May 10, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of May 10, 
2021.
    The FAA must receive comments on this AD by June 7, 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 incorporated by reference (IBR) 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-2021-0317.

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-
0317; 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: Hal Jensen, Aerospace Engineer, 
Operational Safety Branch, Compliance & Airworthiness Division, FAA, 
950 L'Enfant Plaza N SW, Washington, DC 20024; telephone 202-267-9167; 
email hal.jensen@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued AD 2019-17-02, Amendment 39-19722 (84 FR 47410, 
September 10, 2019) (AD 2019-17-02), which applied to Airbus 
Helicopters Deutschland GmbH Model EC135P1, EC135P2, EC135P2+, EC135P3, 
EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters with certain 
longitudinal, collective, and lateral single-axis actuators installed 
having accumulated 6 or more years since manufacturing date or last 
overhaul, whichever occurred later. AD 2019-17-02 required visually 
inspecting for corrosion on all external surfaces of the longitudinal, 
collective, and lateral single-axis actuators, and based on the 
inspection outcome, removing the single-axis actuators from service at 
different compliance times. AD 2019-17-02 also required reporting 
certain information, along with photos of any corrosion, to Airbus 
Helicopters. The FAA issued AD 2019-17-02 to address corrosion in 
certain MRA components, which could result in failure of the component, 
failure of the MRA, and loss of control of the helicopter.

Actions Since AD 2019-17-02 Was Issued

    Since the FAA issued AD 2019-17-02, the agency has determined the 
unsafe condition affects all longitudinal, collective, and lateral 
single-axis actuators that have accumulated 4 or more years since 
manufacturing date or last overhaul. Also, Airbus Helicopters has 
developed repetitive replacement and repetitive inspection procedures 
for the tie bar located in the affected single-axis actuators and 
addresses affected actuators with a manufacturing date or last overhaul 
of more than 4 years and less than 6 years, in addition to the affected 
actuators with a manufacturing date or last overhaul of more than 6 
years.
    The EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2020-0105, dated May 11, 2020 (EASA 
AD 2020-0105) (also referred to as the Mandatory Continuing 
Airworthiness Information, or the MCAI), to correct an unsafe condition 
for all 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, all 
variants, all serial numbers. Model EC635 P2+, EC635 P3, EC635 T1, 
EC635 T2+, and EC635 T3 helicopters are not certificated by the FAA and 
are not included on the U.S. type certificate data sheet except where 
the U.S. type certificate data sheet explains that the Model EC635T2+ 
helicopter having serial number 0858 was converted from Model EC635T2+ 
to Model EC135T2+; this proposed AD therefore does not include Model 
EC635 P2+, EC635 P3, EC635 T1, EC635 T2+, and EC635 T3 helicopters in 
the applicability.
    This AD was prompted by a hard landing of an Airbus Helicopters 
Model

[[Page 21642]]

EC135 helicopter and the discovery of a ruptured and displaced tie bar 
inside the piston of the longitudinal single-axis actuator of the MRA. 
The FAA is issuing this AD to address a ruptured and displaced tie bar 
inside the piston of the longitudinal single-axis actuator of the MRA, 
which could result in reduced control of the helicopter and could 
result in a forced landing with consequent damage to the helicopter and 
injury to occupants. See the MCAI for additional background 
information.

Explanation of Retained Requirements

    Although this AD does not explicitly restate the requirements of AD 
2019-17-02, this AD retains certain requirements of AD 2019-17-02. 
Those requirements are referenced in EASA AD 2020-0105, which, in turn, 
is referenced in paragraph (g) of this AD.

Related IBR Material Under 1 CFR Part 51

    EASA AD 2020-0105 describes procedures for an initial inspection of 
the affected single-axis actuators for corrosion, reporting inspection 
findings, and replacing affected single-axis actuators that have 
corrosion. EASA AD 2020-0105 also describes procedures for an option 
for repetitive replacement or repetitive inspection for corrosion (and 
repair if necessary) of the tie bar located in an affected single-axis 
actuator. 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 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 the State of Design 
Authority, the FAA has been notified of the unsafe condition described 
in the MCAI referenced above. The FAA is issuing this AD after 
evaluating all pertinent information and determining that the unsafe 
condition exists and is likely to exist or develop on other products of 
these same type designs.

Requirements of This AD

    This AD requires accomplishing the actions specified in EASA AD 
2020-0105, 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 MCAI.''

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 2020-0105 
will be incorporated by reference in the FAA final rule. This AD would, 
therefore, require compliance with EASA AD 2020-0105 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 2020-0105 that is 
required for compliance with EASA AD 2020-0105 is available on the 
internet at https://www.regulations.gov by searching for and locating 
Docket No. FAA-2021-0317.

Differences Between This AD and the MCAI

    Where paragraph (4) of EASA AD 2020-0105 provides an option to do 
repetitive inspections of an affected part, this AD would provide an 
option to do repetitive repairs in lieu of the repetitive inspections 
and would require that the repetitive repairs be done using a method 
approved by the Manager, International Validation Branch, FAA.

FAA's 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 foregoing notice and comment prior to adoption of this rule 
because a ruptured and displaced tie bar inside the piston of a 
longitudinal, collective, or lateral single-axis actuator of the MRA 
could result in reduced control of the helicopter, which could result 
in a forced landing with consequent damage to the helicopter and injury 
to occupants. In addition, the compliance time for the initial 
inspection of each affected part is within 14 days after the effective 
date of this AD, which 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, 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.

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-2021-0317; Project Identifier MCAI-
2021-00175-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

[[Page 21643]]

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 Hal Jensen, Aerospace Engineer, Operational Safety Branch, 
Compliance & Airworthiness Division, FAA, 950 L'Enfant Plaza N SW, 
Washington, DC 20024; telephone 202-267-9167; email hal.jensen@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 337 helicopters of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                     Estimated Costs for Required Actions *
----------------------------------------------------------------------------------------------------------------
               Labor cost                   Parts cost         Cost per product         Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
2 work-hours x $85 per hour = $170, per               $0  $170, per inspection cycle  $57,290, per inspection
 inspection cycle.                                                                     cycle.
----------------------------------------------------------------------------------------------------------------
* Table does not include estimated costs for reporting.

    The FAA estimates that it takes about 1 work-hour per product to 
comply with the reporting requirement in this AD. The average labor 
rate is $85 per hour. Based on these figures, the FAA estimates the 
cost of reporting the inspection results on U.S. operators to be 
$28,645, or $85 per product.
    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:

                 Estimated Costs of On-Condition Actions
------------------------------------------------------------------------
           Labor cost                 Parts cost       Cost per product
------------------------------------------------------------------------
6 work-hours x $85 per hour =     Up to $346,802....  Up to $347,312.
 $510.
------------------------------------------------------------------------

    According to the manufacturer, some or all of the costs of this AD 
may be covered under warranty, thereby reducing the cost impact on 
affected individuals. The FAA does not control warranty coverage for 
affected individuals. As a result, the FAA has included all known costs 
in the cost estimate.

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to penalty for 
failure to comply with a collection of information subject to the 
requirements of the Paperwork Reduction Act unless that collection of 
information displays a current valid OMB control number. The control 
number for the collection of information required by this AD is 2120-
0056. The paperwork cost associated with this AD has been detailed in 
the Costs of Compliance section of this document and includes time for 
reviewing instructions, as well as completing and reviewing the 
collection of information. Therefore, all reporting associated with 
this AD is mandatory. Comments concerning the accuracy of this burden 
and suggestions for reducing the burden should be directed to 
Information Collection Clearance Officer, Federal Aviation 
Administration, 10101 Hillwood Pkwy., Fort Worth, TX 76177-1524.

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.

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:

[[Page 21644]]

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

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

Sec.  39.13   [Amended]

0
2. The FAA amends Sec.  39.13 by:
0
a. Removing Airworthiness Directive (AD) 2019-17-02, Amendment 39-19722 
(84 FR 47410, September 10, 2019); and
0
b. Adding the following new AD:

2021-09-07 Airbus Helicopters Deutschland GmbH: Amendment 39-21520; 
Docket No. FAA-2021-0317; Project Identifier MCAI-2021-00175-T.

(a) Effective Date

    This airworthiness directive (AD) becomes effective May 10, 
2021.

(b) Affected ADs

    This AD replaces AD 2019-17-02, Amendment 39-19722 (84 FR 47410, 
September 10, 2019) (AD 2019-17-02).

(c) Applicability

    This AD applies to Airbus Helicopters Deutschland GmbH Model 
EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and 
EC135T3 helicopters, certificated in any category, with any of the 
part numbers specified in paragraphs (c)(1) through (3) of this AD 
installed.
    (1) Longitudinal single-axis actuator part number (P/N) 
L673M20A1008 or P/N L673M30A2111.
    (2) Collective single[hyphen]axis actuator P/N L673M20A1012, P/N 
L673M30A1211, or P/N E673M30A1201.
    (3) Lateral single[hyphen]axis actuator P/N L673M20A1011 or P/N 
L673M30A2311.

(d) Subject

    Joint Aircraft System Component (JASC) Code 67000, Rotorcraft 
Flight Control.

(e) Reason

    This AD was prompted by a hard landing of an Airbus Helicopters 
Deutschland GmbH Model EC135 helicopter and discovery of a ruptured 
and displaced tie bar inside the piston of the longitudinal single-
axis actuator of the main rotor actuator (MRA). The FAA is issuing 
this AD to address a ruptured and displaced tie bar inside the 
piston of a longitudinal, collective, or lateral single-axis 
actuator of the MRA, which could result in reduced control of the 
helicopter and could result in a forced landing with consequent 
damage to the helicopter and injury to occupants.

(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 
2020-0105, dated May 11, 2020 (EASA AD 2020-0105).

(h) Exceptions to EASA AD 2020-0105

    (1) Where EASA AD 2020-0105 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) Where paragraph (4) of EASA AD 2020-0105 refers to Table 1 
of that AD for applicable compliance times, for this AD, use Table 1 
to paragraph (h)(2) of this AD.
[GRAPHIC] [TIFF OMITTED] TR23AP21.098

    (3) Where the ``part calendar age (A)'' and ``part calendar age 
(B)'' definitions of EASA AD 2020-0105 refer to March 29, 2019 
``(ASB [alert service bulletin] reference date)'' and to April 26, 
2019 ``(the effective date of EASA AD 2019-0087-E, dated April 24, 
2019),'' this AD requires using April 23, 2019.
    (4) The ``Remarks'' section of EASA AD 2020-0105 does not apply 
to this AD.
    (5) Where the service information referenced in EASA AD 2020-
0105 specifies to replace a certain part, this AD requires removing 
that part from service or repairing using a method approved by the 
Manager, International Validation Branch, FAA. For a repair method 
to be approved by the Manager, International Validation Branch, as 
required by this paragraph, the Manager's approval letter must 
specifically refer to this AD.
    (6) Paragraph (2) of EASA AD 2020-0105 specifies to report 
inspection results to Airbus Helicopters within a certain compliance 
time. For this AD, report all inspection results at the applicable 
time specified in paragraph (6)(i) or (ii) of this AD.
    (i) If the inspection was done on or after the effective date of 
this AD: Submit the report within 7 days after the inspection.
    (ii) If the inspection was done before the effective date of 
this AD: Submit the report within 7 days after the effective date of 
this AD.
    (7) Where paragraph (4) of EASA AD 2020-0105 provides an option 
to do repetitive replacements or repetitive inspections of an 
affected part, this AD does not allow the option to do repetitive 
inspections. However, this AD does allow repetitive repairs as an 
option to the repetitive replacements specified in paragraph (4) of 
EASA AD 2020-0105. The repetitive repairs must be done using a 
method approved by the Manager, International Validation Branch, 
FAA. For a repair method to be approved by the Manager, 
International Validation Branch, as required by this paragraph, the 
Manager's approval letter must specifically refer to this AD.

[[Page 21645]]

    (8) Where Note 1 of paragraph (4) of EASA AD 2020-0105 permits a 
non-cumulative tolerance of 6 months to be applied to the interval 
for the repetitive replacement or inspection of the affected part, 
this AD requires the repetitive replacement or repair of the 
affected part at intervals not exceeding 5 years 6 months.

(i) Special Flight Permit

    Special flight permits, as described in 14 CFR 21.197 and 
21.199, are prohibited.

(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: 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

    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; telephone 202-267-9167; email hal.jensen@faa.gov.

(l) 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 2020-0105, 
dated May 11, 2020.
    (ii) [Reserved]
    (3) For EASA AD 2020-0105, 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-
2021-0317.
    (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 April 15, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-08574 Filed 4-21-21; 11:15 am]
BILLING CODE 4910-13-P