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Published 2021-07-08 · Federal Register document 2021-14481

Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG (Type Certificate Previously Held by Rolls-Royce Deutschland GmbH, Formerly BMW Rolls-Royce GmbH) Turbofan Engines

Publication summary

The FAA is adopting a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd & Co KG (RRD) BR700-710A1-10, BR700-710A2-20 and BR700-710C4-11 model turbofan engines. This AD was prompted by an investigation by RRD, which revealed a quality escape during the high-pressure turbine (HPT) stage 1 disk rim cooling air hole manufacturing process. This AD requires removing affected HPT disks from service prior to reaching specified compliance times or at the next engine shop visit, whichever occurs first. The FAA is issuing this AD to address the unsafe condition on these products.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:24:08.106391+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2021-9c919420683447c6
Source row
results[235]
Raw source SHA-256
9c919420683447c683ad0c877cb886e341c11862be32b47c536a001b1d76dcb5

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2021-12-07
Effective date printed in this edition
2021-08-12
Read 12 complete recorded clauses
Effective Date
(a) Effective Date

    This AD is effective August 12, 2021.

Exact source excerpt. Text positions 10749–10812, end exclusive, in the original decoded publication. SHA-256: 8e9b8cc63670946b3dd10a52a4b5e5d542e72bfcdadf287232e3baef11701cda

Affected ADs
(b) Affected ADs

    None.

Exact source excerpt. Text positions 10812–10841, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0

Applicability wording · Applicability
(c) Applicability

    This AD applies to Rolls-Royce Deutschland Ltd & Co KG (RRD) 
(Type Certificate previously held by Rolls-Royce Deutschland GmbH, 
formerly BMW Rolls-Royce GmbH) BR700-710A1-10, BR700-710A2-20 and 
BR700-710C4-11 model turbofan engines with a high-pressure turbine 
(HPT) stage 1 disk having a part number and serial number listed in 
Planning Information, paragraph 1.A., of Rolls-Royce Alert Non-

[[Page 36066]]

Modification Service Bulletin (NMSB) SB-BR700-72-A900659, Revision 
1, dated November 5, 2019, installed.

Exact source excerpt. Text positions 10841–11386, end exclusive, in the original decoded publication. SHA-256: d7293b150b0ba6508c73f1bd8f1bdcabd0285a35c5f96fc2d7a22b39e4de5e6c

Subject
(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

Exact source excerpt. Text positions 11386–11490, end exclusive, in the original decoded publication. SHA-256: 151db2778cdfea7f0edc36f3dc91c040e977d403cabb29f1bb70ebf8781db722

Unsafe Condition
(e) Unsafe Condition

    This AD was prompted by an investigation by RRD, which revealed 
a quality escape during the HPT stage 1 disk rim cooling air hole 
manufacturing process. The FAA is issuing this AD to prevent failure 
of the HPT stage 1 disk. The unsafe condition, if not addressed, 
could result in the release of high-energy debris, damage to the 
airplane, and reduced control of the airplane.

Exact source excerpt. Text positions 11490–11898, end exclusive, in the original decoded publication. SHA-256: e8ed7ac3d259118f420288b9dca28371b14f093716d5c0a4957e745a2a785f9a

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 11898–12000, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Required Actions
(g) Required Actions

    Before the affected HPT stage 1 disk exceeds 2,840 flight cycles 
(FCs) since new, or within 60 days after the effective date of this 
AD, whichever occurs later, but not to exceed 8 years after the 
effective date of this AD if using FCs, remove the affected HPT 
stage 1 disk from service and replace with a part eligible for 
installation. Guidance on replacing the HPT stage 1 disk can be 
found in the Accomplishment Instructions, paragraph 3.B., of Rolls-
Royce Alert Non-Modification Service Bulletin (NMSB) SB-BR700-72-
A900659, Revision 1, dated November 5, 2019.

Exact source excerpt. Text positions 12000–12600, end exclusive, in the original decoded publication. SHA-256: 759a1c818befcc3867d7dbf07c8b47e942c1b468141ffa3868a50062252ee559

Installation Prohibition
(h) Installation Prohibition

    After the effective date of this AD, do not install any affected 
HPT stage 1 disk onto any engine.

Exact source excerpt. Text positions 12600–12735, end exclusive, in the original decoded publication. SHA-256: 5c538847675c8941683cc92299391eaad7c12adcc5d50bf24d51ae941c71e19a

Definition
(i) Definition

    For the purpose of this AD, a ``part eligible for installation'' 
is an HPT stage 1 disk that is not listed in paragraph 1.A. of 
Rolls-Royce Alert NMSB SB-BR700-72-A900659, Revision 1, dated 
November 5, 2019.

Exact source excerpt. Text positions 12735–12967, end exclusive, in the original decoded publication. SHA-256: 9505928769aee16aa2deadd8430eeddb04fee2135d8775699c2f1321e8fc5469

Alternative Methods of Compliance (AMOCs)
(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO 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 
certification office, send it to the attention of the person 
identified in Related Information. You may email your request 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.

Exact source excerpt. Text positions 12967–13720, end exclusive, in the original decoded publication. SHA-256: 63d761639459fba92ad3cfa351f51c1dcfb63e83169885acd0cdb099cfc4e03b

Related Information
(k) Related Information

    (1) For more information about this AD, contact Wego Wang, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7134; fax: (781) 238-7199; 
email: [email protected].
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2019-0299, dated December 10, 2019, for more information. You may 
examine the EASA AD in the AD docket on at https://www.regulations.gov by searching for and locating Docket No. FAA-
2020-1174.

Exact source excerpt. Text positions 13720–14230, end exclusive, in the original decoded publication. SHA-256: ffd03ea6b760ace92198f4654a073135286f9584f2ad6b7f91eedf1ee66509c0

Material Incorporated by Reference
(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 the AD specifies otherwise.
    (i) Rolls-Royce Alert Non-Modification Service Bulletin SB-
BR700-72-A900659, Revision 1, dated November 5, 2019.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz 15827, 
Germany; phone: +49 33 7086 4040; email: royce.com">rrd.techhelp@rolls-royce.com.
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (781) 238-7759.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

Exact source excerpt. Text positions 14230–15498, end exclusive, in the original decoded publication. SHA-256: 64a6d3610c797ebc5b3954e73317536e8397a92a740fecde6fc2520b2f4ce57f

No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.

Find all recorded historical references to AD 2021-12-07 · 0 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 0620bd045fb86bbd8028554b4ef0a340ac0a7364395116358c7f960eb796dd4a. Source manifest: 194b09d33c59e314e78ae5946c2bb8c5159b5351ed22e4f8376527a50a754f21.

Official source · 2021-07-08

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[Federal Register Volume 86, Number 128 (Thursday, July 8, 2021)]
[Rules and Regulations]
[Pages 36064-36066]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-14481]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-1174; Project Identifier MCAI-2019-00135-E; 
Amendment 39-21594; AD 2021-12-07]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG 
(Type Certificate Previously Held by Rolls-Royce Deutschland GmbH, 
Formerly BMW Rolls-Royce GmbH) Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Rolls-Royce Deutschland Ltd & Co KG (RRD) BR700-710A1-10, 
BR700-710A2-20 and BR700-710C4-11 model turbofan engines. This AD was 
prompted by an investigation by RRD, which revealed a quality escape 
during the high-pressure turbine (HPT) stage 1 disk rim cooling air 
hole manufacturing process. This AD requires removing affected HPT 
disks from service prior to reaching specified compliance times or at 
the next engine shop visit, whichever occurs first. The FAA is issuing 
this AD to address the unsafe condition on these products.

DATES: This AD is effective August 12, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of August 12, 
2021.

ADDRESSES: For service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz 15827, 
Germany; phone: +49 33 7086 4040; email: royce.com">rrd.techhelp@rolls-royce.com. 
You may view this service information at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (781) 238-7759. It is also available at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2020-1174.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-1174; or in person at 
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The AD docket contains this final rule, the 
mandatory continuing airworthiness information (MCAI), 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.

FOR FURTHER INFORMATION CONTACT: Wego Wang, Aviation Safety Engineer, 
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 
(781) 238-7134; fax: (781) 238-7199; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to certain RRD BR700-
710A1-10, BR700-710A2-20 and BR700-710C4-11 model turbofan engines. The 
NPRM published in the Federal Register on January 21, 2021 (86 FR 
6271). The NPRM was prompted by an investigation by RRD, which revealed 
a quality escape during the HPT stage 1 disk rim cooling air hole 
manufacturing process. In the NPRM, the FAA proposed to require 
removing affected HPT disks from service prior to reaching specified 
compliance times or at the next engine shop visit, whichever occurs 
first. The FAA is issuing this AD to address the unsafe condition on 
these products.
    The European Union Aviation Safety Agency (EASA), which is the 
Technical Agent for the Member States of the European Community, has 
issued EASA AD 2019-0299, dated December 10, 2019 (referred to after 
this as ``the MCAI''), to address the unsafe condition on these 
products. The MCAI states:

    An occurrence was reported of an HPT stage 1 disc burst on an 
industrial gas turbine engine. Subsequent investigation revealed a 
quality escape during HPT stage 1 disc rim cooling air hole 
manufacturing process. A review revealed that 28 HPT stage 1 discs 
were subject to a similar quality escape, two of which have been 
recovered and removed from service. The consequence of this 
manufacturing error is that the affected parts can no longer safely 
reach their Declared Safe Cyclic Life (DSCL).
    This condition, if not corrected, may lead to failure of an 
affected part, possibly resulting in release of high-energy debris, 
with consequent damage to, and/or reduced control of, the aeroplane. 
To address this potentially unsafe condition, RRD issued the NMSB, 
providing instructions to remove the engine from service for in-shop 
replacement of the affected part.
    For the reasons described above, this [EASA] AD reduces the DSCL 
for the affected

[[Page 36065]]

parts, requires identification of the affected parts and removal 
from service of each affected engine for replacement of the affected 
part. This [EASA] AD also prohibits (re)installation of affected 
parts.

    You may obtain further information by examining the MCAI in the AD 
docket at https://www.regulations.gov by searching for and locating 
Docket No. FAA-2020-1174.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from two commenters. The commenters were 
the Air Line Pilots Association, International (ALPA) and an anonymous 
commenter. ALPA supported the NPRM without change. The anonymous 
commenter supported the NPRM but stated their opinion on the estimated 
costs.

Request for Rolls-Royce To Share Replacement Part Cost

    An anonymous commenter indicated that Rolls-Royce could share the 
cost of new HPT disks since it was their manufacturing process that 
caused the defects in the HPT disks.
    The FAA does not determine who pays for the costs of an AD. The 
Estimated Costs paragraph indicates that, according to the 
manufacturer, all of the costs of this AD may be covered under a 
manufacturer warranty, thereby reducing the cost impact on affected 
operators.

Conclusion

    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 products. Except for minor editorial changes, this 
AD is adopted as proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Rolls-Royce Alert Non-Modification Service 
Bulletin (NMSB) SB-BR700-72-A900659, Revision 1, dated November 5, 2019 
(the NMSB). The Alert NMSB provides the part numbers and serial numbers 
for affected HPT disks, the serial numbers for all engines with an 
affected HPT disk installed, and instructions for replacement of the 
affected HPT disk. This service information is reasonably available 
because the interested parties have access to it through their normal 
course of business or by the means identified in ADDRESSES.

Costs of Compliance

    The FAA estimates that this AD affects 21 engines installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Replace HPT disk......................  20 work-hours x $85 per         $550,000        $551,700     $11,585,700
                                         hour = $1,700.
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, all of the costs of this AD may 
be covered under warranty, thereby reducing the cost impact on affected 
operators.

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 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.

Adoption of 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:

2021-12-07 Rolls-Royce Deutschland Ltd & Co KG (Type Certificate 
previously held by Rolls-Royce Deutschland GmbH, formerly BMW Rolls-
Royce GmbH): Amendment 39-21594; Docket No. FAA-2020-1174; Project 
Identifier MCAI-2019-00135-E.

(a) Effective Date

    This AD is effective August 12, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Rolls-Royce Deutschland Ltd & Co KG (RRD) 
(Type Certificate previously held by Rolls-Royce Deutschland GmbH, 
formerly BMW Rolls-Royce GmbH) BR700-710A1-10, BR700-710A2-20 and 
BR700-710C4-11 model turbofan engines with a high-pressure turbine 
(HPT) stage 1 disk having a part number and serial number listed in 
Planning Information, paragraph 1.A., of Rolls-Royce Alert Non-

[[Page 36066]]

Modification Service Bulletin (NMSB) SB-BR700-72-A900659, Revision 
1, dated November 5, 2019, installed.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

(e) Unsafe Condition

    This AD was prompted by an investigation by RRD, which revealed 
a quality escape during the HPT stage 1 disk rim cooling air hole 
manufacturing process. The FAA is issuing this AD to prevent failure 
of the HPT stage 1 disk. The unsafe condition, if not addressed, 
could result in the release of high-energy debris, damage to the 
airplane, and reduced control of the airplane.

(f) Compliance

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

(g) Required Actions

    Before the affected HPT stage 1 disk exceeds 2,840 flight cycles 
(FCs) since new, or within 60 days after the effective date of this 
AD, whichever occurs later, but not to exceed 8 years after the 
effective date of this AD if using FCs, remove the affected HPT 
stage 1 disk from service and replace with a part eligible for 
installation. Guidance on replacing the HPT stage 1 disk can be 
found in the Accomplishment Instructions, paragraph 3.B., of Rolls-
Royce Alert Non-Modification Service Bulletin (NMSB) SB-BR700-72-
A900659, Revision 1, dated November 5, 2019.

(h) Installation Prohibition

    After the effective date of this AD, do not install any affected 
HPT stage 1 disk onto any engine.

(i) Definition

    For the purpose of this AD, a ``part eligible for installation'' 
is an HPT stage 1 disk that is not listed in paragraph 1.A. of 
Rolls-Royce Alert NMSB SB-BR700-72-A900659, Revision 1, dated 
November 5, 2019.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO 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 
certification office, send it to the attention of the person 
identified in Related Information. You may email your request 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

    (1) For more information about this AD, contact Wego Wang, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7134; fax: (781) 238-7199; 
email: [email protected].
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2019-0299, dated December 10, 2019, for more information. You may 
examine the EASA AD in the AD docket on at https://www.regulations.gov by searching for and locating Docket No. FAA-
2020-1174.

(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 the AD specifies otherwise.
    (i) Rolls-Royce Alert Non-Modification Service Bulletin SB-
BR700-72-A900659, Revision 1, dated November 5, 2019.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz 15827, 
Germany; phone: +49 33 7086 4040; email: royce.com">rrd.techhelp@rolls-royce.com.
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (781) 238-7759.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on June 14, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-14481 Filed 7-7-21; 8:45 am]
BILLING CODE 4910-13-P


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76f6dedfc7204b2a2c2768c2f96338c17e813dd7e6f51cef59b832bba34c2340
Text SHA-256
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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.

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