[Federal Register Volume 89, Number 179 (Monday, September 16, 2024)]
[Rules and Regulations]
[Pages 75472-75475]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-20969]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2238; Project Identifier MCAI-2023-00698-R; 
Amendment 39-22803; AD 2024-15-11]
RIN 2120-AA64


Airworthiness Directives; Leonardo S.p.a. Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
Leonardo S.p.a. Model A109C, A109E, A109K2, A109S, and AW109SP 
helicopters. This AD was prompted by reports of loose tail rotor duplex 
bearing locking nuts, possibly caused by improper installation. This AD 
requires disassembling certain tail rotor duplex bearings and 
reassembling them in accordance with updated procedures. This AD also 
prohibits installing certain tail rotor duplex bearing housings and 
pitch change slider assemblies. These actions are specified in a 
European Union Aviation Safety Agency (EASA) 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 October 21, 2024.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of October 21, 
2024.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2023-2238; 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, any comments received, and other 
information. The address for Docket Operations is U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
    Material Incorporated by Reference:
     For EASA material identified in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 
000; email: [email protected]; website: easa.europa.eu. You may find 
the EASA material on the EASA website at 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 at 
regulations.gov under Docket No. FAA-2023-2238.

FOR FURTHER INFORMATION CONTACT: William McCully, Aviation Safety 
Engineer, FAA, International Validation Branch, FAA, 1600 Stewart Ave. 
Suite 410, Westbury, NY 11590; phone: (404) 474-5548; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Background

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2023-0105, dated May 23, 2023 (EASA 
AD 2023-0105), to correct an unsafe condition on Leonardo S.p.A. Model 
A109C, A109E, A109K2, A109LUH, A109S, and AW109SP helicopters.
    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to all Leonardo S.p.a. 
Model A109C, A109E, A109K2, A109S, and AW109SP helicopters. The NPRM 
published in the Federal Register on December 11, 2023 (88 FR 85856). 
The

[[Page 75473]]

NPRM was prompted by reports of loose tail rotor duplex bearing locking 
nuts. Investigations identified incorrect accomplishment of the 
assembly and continued maintenance instructions of the tail rotor 
duplex bearing housing and slider group as the most likely root cause 
of that loosening. Accordingly, the NPRM proposed to require 
disassembling certain tail rotor duplex bearing housings and pitch 
change slider assemblies and reassembling them in accordance with 
updated procedures. The NPRM also proposed to prohibit installing 
certain tail rotor duplex bearing housings and pitch change slider 
assemblies. These actions are specified in EASA AD 2023-0105.
    The FAA is issuing this AD to detect and address the incorrect 
assembly of the tail rotor duplex bearing. This unsafe condition, if 
not addressed, could lead to failure of the tail rotor function, 
possibly resulting in loss of control of the helicopter. See EASA AD 
2023-0105 for additional background information.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from one commenter, Air Methods. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Comments Regarding Compliance With Updated Maintenance Procedures

    Air Methods commented that, upon review of the ASB [alert service 
bulletin] and the existing MM [maintenance manual], changes to the MM 
appear to be relatively minor between the existing MM procedures and 
the updated maintenance procedures (defined in EASA AD 2023-0105 as 
``the updated procedure'' and that are included in the alert service 
bulletins \1\ that are referenced for compliance). Air Methods also 
requested the FAA to advise of the reasoning behind the proposed AD 
requirement when the maintenance procedures should get updated to 
accurately reflect the new work steps and this area has a 180-day 
recurrent inspection.
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    \1\ Leonardo Helicopters Alert Service Bulletin (ASB) No. 109-
158, ASB No. 109EP-180, ASB No. 109K-076, ASB No. 109S-115, and ASB 
No. 109SP-154, each dated March 21, 2023, contain updated 
maintenance procedures (referenced as ``Annex A'' or ``Annex B'' in 
the ASBs, as applicable) for assembling the tail rotor housing and 
slider assembly. The updated maintenance procedures are MM Paragraph 
64-30-3 Revision 5, MM Paragraph 64-31-6 Revision 16, MM Paragraph 
64-30-5 Revision 5, MM Paragraph 64-31-6 Rev. 6, and AMP DM 0B-A-64-
31-06-00A-710A-B Issue 13, as applicable. The identified ASBs are 
referenced in EASA AD 2023-0105 for compliance and will be available 
at regulations.gov under Docket No. FAA-2023-2238 after this FAA 
final rule is published.
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    The FAA infers that Air Methods is requesting justification of the 
proposed requirement in the NPRM to replace an affected part, as 
defined in EASA AD 2023-0105, with a serviceable part, as defined in 
EASA AD 2023-0105, which may be done by following certain maintenance 
procedures to disassemble the affected part and updated maintenance 
procedures to reassemble the affected part, instead of allowing for 
accomplishment of anticipated updated maintenance procedures to address 
the unsafe condition without an AD. The FAA cannot require a 
manufacturer to revise its maintenance publications and, operators are 
subject to the specific manufacturer's maintenance procedures at time 
of delivery, which may vary. Therefore, to mandate specific procedures 
when an unsafe condition has been determined, the FAA must issue an AD 
to address and correct that unsafe condition. Lastly, compliance times 
in AD actions commonly specify multiple compliance time units to 
capture varying usage of the fleet and various factors related to the 
unsafe condition. The compliance time proposed by the NPRM to 
accomplish the replacement is within 100 hours time-in-service or 6 
months, whichever occurs first. The purpose of the ``within 100 hours 
time-in-service'' compliance time unit is to capture high usage 
helicopters, which have an increased likeliness of occurrence of a 
failure, that a 180-day compliance time alone would not capture to an 
acceptable level of safety.

Comments Regarding Compliance With Future Revisions of the Updated 
Maintenance Procedures

    Air Methods stated that there are three levels of documents to 
comply with to accomplish the proposed AD; EASA AD 2023-0105, the ASB 
[alert service bulletins] (that are referred to as ``the ASB'' and 
referenced in EASA AD 2023-0105 for compliance), and MM [maintenance 
manual] (particularly, maintenance procedures, that are referenced in 
the alert service bulletins for compliance and are normally available 
in maintenance publications). Air Methods also stated that the proposed 
AD does not address future revisions of the updated maintenance 
procedures identified in EASA AD 2023-0105 (defined in EASA AD 2023-
0105 as ``the updated procedure'') and the alert service bulletins.
    The NPRM proposed to require accomplishing the required actions and 
compliance times specified in EASA AD 2023-0105 with certain 
exceptions. Through that incorporation, the NPRM proposed to allow 
using future revisions of the maintenance procedures because EASA AD 
2023-0105 defines ``the updated procedure'' by identifying certain 
revisions of the maintenance procedures for the applicable model 
helicopters and explicitly states ``or later revisions;'' and, the NPRM 
did not propose an exception to prohibit using later revisions of the 
updated maintenance procedures. The NPRM did not propose compliance 
with part II of the alert service bulletins.
    Air Methods asked if the FAA intends to require an AD logbook 
signoff each time this area is disassembled/reassembled after the 
initial task compliance. Air Methods also asked if the signoff with the 
``the updated procedure'' as identified in EASA AD 2023-0105, or later, 
is sufficient for future maintenance as it is impossible to forecast 
unplanned maintenance and the current version of the maintenance 
procedures would be used for this maintenance.
    The requirements proposed in the NPRM do not require an AD logbook 
signoff each time the tail rotor duplex bearing housing or pitch change 
slider assembly are disassembled and reassembled. The NPRM proposed to 
require a one-time replacement, and compliance must be entered into the 
helicopter maintenance records in accordance with 14 CFR 43.9(a) and 
91.417(a)(2)(v) for that one-time replacement. Thereafter, the NPRM 
proposed to prohibit installing any tail rotor duplex bearing housing 
part number (P/N) 109-0130-94-XXX and any pitch change slider assembly 
P/N 109-0130-91-XXX (with ``XXX'' representing any numerical sequence) 
that has been disassembled and (re)assembled in service using 
maintenance procedures issued prior to the updated procedure, as 
defined in EASA AD 2023-0105. There is no logbook entry for part 
installation prohibitions because the identified parts must not be 
installed on any helicopters.

Additional Changes Since the NPRM Was Issued

    Since the FAA issued the NPRM, two errors in EASA AD 2023-0105 have 
been identified. EASA AD 2023-0105 inadvertently omits ``MM Paragraph 
64-31-6 Rev. 6'' (for certain serial-numbered Model A109K2 helicopters) 
in its definition of ``the updated procedure'' and inadvertently 
identifies the updated procedures as ``(as referenced in Annex A of the 
ASB).''

[[Page 75474]]

The FAA is correcting the omission by adding an exception to revise the 
definition of ``the updated procedure'' and is correcting the 
misidentification by adding an exception to replace that text with 
``(as referenced in Annex A or B of the ASB, as applicable).'' These 
corrections are relieving as they reduce the population of ``affected 
parts'' as defined in EASA AD 2023-0105.

Conclusion

    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 reviewed the relevant 
data, considered the comments received, and determined that air safety 
requires adopting this AD as proposed. Accordingly, the FAA is issuing 
this AD to address the unsafe condition on these helicopters. Except 
for the changes described previously and minor editorial changes, this 
AD is adopted as proposed in the NPRM. None of the changes will 
increase the economic burden on any operator.

Material Incorporated by Reference Under 1 CFR Part 51

    EASA AD 2023-0105 requires replacing certain parts through the 
disassembly and reassembly of the tail rotor duplex bearing and the 
pitch change slider assembly. EASA AD 2023-0105 also prohibits 
installing certain parts on any helicopter.
    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.

Differences Between This AD and the EASA

    EASA AD 2023-0105 applies to Model A109LUH helicopters, whereas 
this AD does not because that model is not FAA type-certificated.

Costs of Compliance

    The FAA estimates that this AD affects 160 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.
    Disassembly and reassembly of the tail rotor housing and slider 
assembly will take approximately 8 work-hours for an estimated cost of 
$680 per helicopter and $108,800 for the U.S. fleet.

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,
    (2) Will not affect intrastate aviation in Alaska, and
    (3) Will 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 Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

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 adding the following new airworthiness 
directive:

2024-15-11 Leonardo S.p.a.: Amendment 39-22803; Docket No. FAA-2023-
2238; Project Identifier MCAI-2023-00698-R.

(a) Effective Date

    This airworthiness directive (AD) is effective October 21, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Leonardo S.p.a. Model A109C, A109E, 
A109K2, A109S, and AW109SP helicopters, certificated in any 
category.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of loose tail rotor duplex 
bearing locking nuts, possibly caused by improper installation. The 
FAA is issuing this AD to detect and address the incorrect assembly 
of the tail rotor duplex bearing. The unsafe condition, if not 
addressed, could lead to failure of the tail rotor function, 
possibly resulting in 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 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) AD 
2023-0105, dated May 23, 2023 (EASA AD 2023-0105).

(h) Exceptions to EASA AD 2023-0105

    (1) Where EASA AD 2023-0105 defines the updated procedure as 
``Paragraph 64-30-3 Rev. 5 (for A109C helicopters), MM Paragraph 64-
31-6 Rev. 16 (for A109E helicopters), MM Paragraph 64-30-5 Rev. 5 
(for A109K2 helicopters), AM DM 64-31-10-00A-710A-B Issue 13 (for 
A109LUH helicopters) or AMP DM 0B-A-64-31-06-00A-710A-B Issue 13 
(for A109S and AW109SP helicopters), as applicable, or later 
revisions;'' for this AD, replace that text with ``Paragraph 64-30-3 
Rev. 5 (for A109C helicopters), MM Paragraph 64-31-6 Rev. 16 (for 
A109E helicopters), MM Paragraph 64-30-5 Rev. 5 or MM Paragraph 64-
31-6 Rev. 6, as applicable (for A109K2 helicopters), or AMP DM 0B-A-
64-31-06-00A-710A-B Issue 13 (for A109S and AW109SP helicopters), as 
applicable, or later revisions.''
    (2) Where EASA AD 2023-0105 states ``Annex A of the ASB;'' for 
this AD, replace that text with ``Annex A or B of the ASB, as 
applicable.''
    (3) Where EASA AD 2023-0105 requires compliance in terms of 
flight hours, this AD requires using hours time-in-service.
    (4) Where EASA AD 2023-0105 refers to its effective date, this 
AD requires using the effective date of this AD.

[[Page 75475]]

    (5) Where the material referenced in EASA AD 2023-0105 specifies 
to ``discard'' parts; for this AD, replace that text with ``remove 
from service.''
    (6) This AD does not adopt the ``Remarks'' section of EASA AD 
2023-0105.

(i) No Reporting Requirement

    Although the material referenced in EASA AD 2023-0105 specifies 
to submit certain information to the manufacturer, this AD does not 
include that requirement.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation Branch, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, 
send your request to your principal inspector or local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (k) of 
this AD. Information may be emailed to: [email protected].
    (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 William McCully, 
Aviation Safety Engineer, FAA, International Validation Branch, FAA, 
1600 Stewart Ave., Suite 410, Westbury, NY 11590; phone: (404) 474-
5548; email: [email protected].

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the material listed in this paragraph 
under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless this AD specifies otherwise.
    (i) European Union Aviation Safety Agency (EASA) AD 2023-0105, 
dated May 23, 2023.
    (ii) [Reserved]
    (3) For EASA material identified in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 
000; email: [email protected]; website: easa.europa.eu. You may 
find the EASA material on the EASA website at ad.easa.europa.eu.
    (4) 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.
    (5) You may view this material 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/[email protected]">www.archives.gov/federal-register/cfr/[email protected].

    Issued on September 10, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-20969 Filed 9-13-24; 8:45 am]
BILLING CODE 4910-13-P