[Federal Register Volume 86, Number 177 (Thursday, September 16, 2021)]
[Rules and Regulations]
[Pages 51600-51604]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-19982]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0306; Project Identifier MCAI-2020-01493-E; 
Amendment 39-21706; AD 2021-18-05]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2020-15-12 
for certain Rolls-Royce Deutschland Ltd & Co KG (RRD) Trent 1000 model 
turbofan engines. AD 2020-15-12 required initial and repetitive 
ultrasonic or visual inspections of the intermediate-pressure 
compressor (IPC) stage 1 rotor blade root (front face), IPC stage 2 
rotor blade root (front and rear face), and IPC shaft stage 2 dovetail 
post (front face), and removal of any cracked parts from service. AD 
2020-15-12 also required an inspection after asymmetric power and cabin 
depressurization events. This AD was prompted by IPC rotor blade 
separations resulting in engine failures. This AD requires initial and 
repetitive ultrasonic or visual inspections of certain IPC stage 1 
rotor blade root, IPC stage 2 rotor blade root, and IPC shaft stage 2 
dovetail posts until replacement of the IPC stage 1 and stage 2 rotor 
blades with redesigned IPC stage 1 and stage 2 rotor blades in kitted 
sets. The FAA is issuing this AD to address the unsafe condition on 
these products.

DATES: This AD is effective October 21, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of October 21, 
2021.

[[Page 51601]]


ADDRESSES: For service information identified in this final rule, 
contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, 
DE24 8BJ, United Kingdom; phone: +44 (0)1332 242424; fax: +44 (0)1332 
249936; website: https://www.rolls-royce.com/contact-us.aspx. 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-2021-
0306.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0306; 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.

FOR FURTHER INFORMATION CONTACT: Kevin Clark, Aviation Safety Engineer, 
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 
(781) 238-7088; 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 to supersede AD 2020-15-12, Amendment 39-21175 (85 FR 
45081, July 27, 2020), (AD 2020-15-12). AD 2020-15-12 applied to 
certain RRD Trent 1000-A2, Trent 1000-AE2, Trent 1000-C2, Trent 1000-
CE2, Trent 1000-D2, Trent 1000-E2, Trent 1000-G2, Trent 1000-H2, Trent 
1000-J2, Trent 1000-K2, and Trent 1000-L2 model turbofan engines. The 
NPRM published in the Federal Register on April 22, 2021 (86 FR 21233). 
The NPRM was prompted by IPC rotor blade separations resulting in 
engine failures. Subsequently, the manufacturer identified the need to 
add new inspections and an optional terminating action, amend the 
asymmetric power condition for engine inspection, and to add an 
inspection after a cabin depressurization event. In the NPRM, the FAA 
proposed to continue to require initial and repetitive ultrasonic or 
visual inspection of the IPC stage 1 rotor blade root (front face), IPC 
stage 2 rotor blade root (front and rear face), and IPC shaft stage 2 
dovetail post (front face), removal of any cracked parts from service, 
and an inspection after asymmetric power and cabin depressurization 
events until the installation of the IPC stage 1 and stage 2 rotor 
blades with the IPC stage 1 and stage 2 rotor blades in kitted sets. 
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 2020-0240, dated November 5, 2020 (referred to after 
this as ``the MCAI''), to address the unsafe condition on these 
products. The MCAI states:

    Occurrences were reported on Rolls-Royce Trent 1000 `Pack C' 
engines, where some IPC Rotor 1 and Rotor 2 blades were found 
cracked.
    This condition, if not detected and corrected, could lead to in-
flight blade release, possibly resulting in reduced control of the 
aeroplane.
    To address this potential unsafe condition, Rolls-Royce 
initially issued Alert NMSB TRENT 1000 72-AJ814 and 72-AJ819 to 
provide inspection instructions for IPC Rotor 1 blades, and IPC 
Rotor 2 blades and IPC shaft Stage 2 dovetail posts, respectively. 
Rolls-Royce also issued NMSB TRENT 1000 72-J871 to provide rework 
instructions for the affected parts, and Alert NMSB TRENT 1000 72-
AJ869 to inspect those post-rework parts. Consequently, EASA issued 
AD 2017-0248 to require repetitive inspections of the affected IPC 
Rotor blades and IPC shaft Stage 2 dovetail posts and, depending on 
findings, removal from service of the engine for corrective action.
    After that [EASA] AD was issued, Rolls-Royce issued Alert NMSB 
TRENT 1000 72-AK058 to provide instructions for a one-time on-wing 
inspection. Consequently, EASA issued AD 2018-0073, retaining the 
requirements of EASA AD 2017-0248, which was superseded, to require 
an additional borescope inspection of certain engines and, depending 
on findings, removal from service of the engine for corrective 
action.
    After that [EASA] AD was issued, it was determined that 
repetitive borescope inspections are necessary on all engines to 
ensure fleet-wide continued safe operation. Consequently, Rolls-
Royce revised Alert NMSB TRENT 1000 72-AJ869, Alert NMSB TRENT 1000 
72-AJ814, Alert NMSB TRENT 1000 72-AJ819 and NMSB TRENT 1000 72-
J871, and issued NMSB TRENT 1000 72-AK060 to consolidate all 
inspection instructions. Consequently, EASA issued AD 2018-0084 
(later revised), retaining the requirements of EASA AD 2018-0073, 
which was superseded, and requiring repetitive on-wing borescope 
inspections of the affected Rotor 1 parts and affected Rotor 2 parts 
and, depending on findings, removal from service of the engine for 
corrective action. That [EASA] AD also introduced specific 
requirements for engines installed on aeroplanes involved in ETOPS, 
and inspection following operation in asymmetric power conditions.
    Rolls-Royce then introduced NMSB Trent 1000 72-AK092 to provide 
inspections for the rear face of the Rotor 2 blades and NMSB TRENT 
1000 72-AK060 was revised (R1) accordingly. Later, Rolls-Royce 
developed mod 72-J941, installing improved IPC Stage 1 and Stage 2 
rotor blades, and issued the modification SB, providing the 
necessary instructions for in-service application. EASA issued AD 
2018-0084R2 to exclude post-mod 72-J941 engines from the 
Applicability and introducing the modification SB as terminating 
action for the repetitive inspections as required by that [EASA] AD.
    After that [EASA] AD was issued, Rolls-Royce issued NMSB TRENT 
1000 72-AK313 and revised Alert NMSB TRENT 1000 72-AJ814, 72-AJ819 
and 72-AK092 to introduce new inspections, new thresholds and new 
intervals, depending on engine configuration. These inspections are 
for all operations, ETOPS and non-ETOPS. The latest revision of the 
NMSB also amended the asymmetric power conditions for engine 
inspection and introduced cabin depressurisation as an event to 
trigger engine inspection(s).
    Consequently, EASA issued AD 2019-0250 to require introduction 
of the new inspections, replacing those previously imposed by EASA 
AD 2018-0084R2 (through NMSB TRENT 1000 72-AK060), and to remove the 
references to Engine Health Monitoring messages and ETOPS-related 
requirements.
    Since that [EASA] AD was issued, it was discovered that the 
manufacturing distribution of the individual blade frequencies could 
differ from the assumed values during certification of the SB TRENT 
1000 72-J941, which means there may not be sufficient margin to 
prevent the blades from experiencing high vibration levels. Prompted 
by these findings, Rolls-Royce issued the modification SB to provide 
blade kitting instructions.

    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-2021-0306.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from 1 commenter. The commenter was The 
Boeing Company (Boeing). Boeing supported the NPRM without change.

Conclusion

    The FAA reviewed the relevant data, considered the comment 
received, and determined that air safety requires adopting the 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.

[[Page 51602]]

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Rolls-Royce Alert Non-Modification Service 
Bulletin (NMSB) Trent 1000 72-AK313, Revision 1, dated August 22, 2019; 
and Rolls-Royce Alert Service Bulletin (SB) Trent 1000 72-AK430, 
Initial Issue, dated August 17, 2020. Rolls-Royce Alert NMSB Trent 1000 
72-AK313 defines the initial inspection threshold and repeat inspection 
intervals for Trent 1000 IPC stage 1 rotor blade, IPC stage 2 rotor 
blade, and IPC shaft stage 2 dovetail posts. Rolls-Royce Alert SB Trent 
1000 72-AK430 introduces the IPC stage 1 and stage 2 rotor blades in 
kitted sets and provides kitting instructions. 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.

Other Related Service Information

    The FAA reviewed Rolls-Royce Alert NMSB Trent 1000 72-AJ814, 
Revision 5, dated May 3, 2019; Rolls-Royce Alert NMSB Trent 1000 72-
AJ819, Revision 4, dated May 3, 2019; Rolls-Royce Alert NMSB Trent 1000 
72-AK092, Revision 4, dated May 3, 2019; Rolls-Royce SB Trent 1000 72-
J871, Revision 6, dated December 12, 2019; and Rolls-Royce SB Trent 
1000 72-J941, Revision 1, dated February 6, 2019.
    Rolls-Royce Alert NMSB Trent 1000 72-AJ814 describes procedures for 
performing an ultrasonic inspection (USI) of the IPC stage 1 rotor 
blades. Rolls-Royce Alert NMSB Trent 1000 72-AJ819 describes procedures 
for performing a visual borescope inspection of the IPC stage 2 rotor 
blades and IPC shaft stage 2 dovetail posts. Rolls-Royce Alert NMSB 
Trent 1000 72-AK092 describes procedures for performing a USI of the 
IPC stage 2 rotor blades. Rolls-Royce SB Trent 1000 72-J871 describes 
procedures for reworking or replacing the affected parts. Rolls-Royce 
SB Trent 1000 72-J941 specifies procedures for installing the 
redesigned IPC stage 1 and stage 2 rotor blades.

Costs of Compliance

    The FAA estimates that this AD affects 7 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
----------------------------------------------------------------------------------------------------------------
Inspect the IPC stage 1 rotor blade     20 work-hours x $85 per               $0          $1,700         $11,900
 root (Front Face).                      hour = $1,700.
Inspect the IPC stage 2 rotor blade     6 work-hours x $85 per                 0             510           3,570
 root (Front Face) and IPC shaft stage   hour = $510.
 2 dovetail post (Front Face).
Inspect the IPC stage 2 rotor blade     10 work-hours x $85 per                0             850           5,950
 root (Rear Face).                       hour = $850.
Replace all 34 IPC stage 1 rotor        280 work-hours x $85 per          52,360          76,160         533,120
 blades (mandatory terminating action).  hour = $23,800.
Replace all 49 IPC stage 2 rotor        280 work-hours x $85 per          48,755          72,555         507,885
 blades (mandatory terminating action).  hour = $23,800.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements that would be required based on the results of the 
inspection. The agency has no way of determining the number of aircraft 
that might need these replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace all 34 IPC stage 1 rotor blades.......  280 work-hours x $85 per hour =          $52,360         $76,160
                                                 $23,800.
Replace all 49 IPC stage 2 rotor blades.......  280 work-hours x $85 per hour =           48,755          72,555
                                                 $23,800.
Replace the IPC drum assembly.................  144 work-hours x $85 per hour =        1,370,000       1,382,240
                                                 $12,240.
----------------------------------------------------------------------------------------------------------------

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 has determined that 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.

[[Page 51603]]

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:
0
a. Removing Airworthiness Directive AD 2020-15-12, Amendment 39-21175 
(85 FR 45081, July 27, 2020); and
0
b. Adding the following new airworthiness directive:

2021-18-05 Rolls-Royce Deutschland Ltd & Co KG (Type Certificate 
previously held by Rolls-Royce plc): Amendment 39-21706; Docket No. 
FAA-2021-0306; Project Identifier MCAI-2020-01493-E.

(a) Effective Date

    This airworthiness directive (AD) is effective October 21, 2021.

(b) Affected ADs

    This AD replaces AD 2020-15-12, Amendment 39-21175 (85 FR 45081, 
July 27, 2020).

(c) Applicability

    This AD applies to Rolls-Royce Deutschland Ltd & Co KG (Type 
Certificate previously held by Rolls-Royce plc) Trent 1000-A2, Trent 
1000-AE2, Trent 1000-C2, Trent 1000-CE2, Trent 1000-D2, Trent 1000-
E2, Trent 1000-G2, Trent 1000-H2, Trent 1000-J2, Trent 1000-K2, and 
Trent 1000-L2 model turbofan engines, except those that have the 
redesigned intermediate-pressure compressor (IPC) stage 1 and stage 
2 rotor blades introduced by Rolls-Royce (RR) Service Bulletin (SB) 
Trent 1000 72-J941, Initial Issue, dated December 6, 2016, or 
Revision 1, dated February 6, 2019.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by IPC rotor blade separations resulting in 
engine failures. The FAA is issuing this AD to prevent failure of 
the IPC. The unsafe condition, if not addressed, could result in 
failure of one or more engines, loss of thrust control, and loss of 
the airplane.

(f) Compliance

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

(g) Required Actions

    (1) After the effective date of this AD, before exceeding the 
initial inspection thresholds and repeat inspection intervals 
specified in Table 1 of RR Alert Non-Modification Service Bulletin 
(NMSB) Trent 1000 72-AK313, Revision 1, dated August 22, 2019 (RR 
NMSB Trent 1000 72-AK313 R1):
    (i) Perform initial ultrasonic inspections (USIs) of the IPC 
stage 1 rotor blade root (front face).
    (ii) Thereafter, perform repetitive USIs of the IPC stage 1 
rotor blade root (front face).
    (iii) Use the Accomplishment Instructions, paragraph 3.A.(1)(a) 
(on-wing) or 3.A.(2)(a) and (b) (in-shop), of RR NMSB Trent 1000 72-
AK313 R1 to perform the inspections.
    (2) After the effective date of this AD, before exceeding the 
initial inspection thresholds and repeat inspection intervals 
specified in Table 2 of RR NMSB Trent 1000 72-AK313 R1:
    (i) Perform initial visual inspections of the IPC stage 2 rotor 
blade root (front face) and IPC shaft stage 2 dovetail post (front 
face).
    (ii) Thereafter, perform repetitive visual inspections of the 
IPC stage 2 rotor blade root (front face) and IPC shaft stage 2 
dovetail post (front face).
    (iii) Use the Accomplishment Instructions, paragraph 3.B.(1)(a) 
(on-wing) or 3.B.(2)(b) (in-shop), of RR NMSB Trent 1000 72-AK313 R1 
to perform the inspections.
    (3) After the effective date of this AD, before exceeding the 
initial inspection threshold and repeat inspection intervals 
specified in Table 2 of RR NMSB Trent 1000 72-AK313 R1:
    (i) Perform initial USIs of IPC stage 2 rotor blade root (rear 
face).
    (ii) Thereafter, perform repetitive USIs of IPC stage 2 rotor 
blade root (rear face).
    (iii) Use the Accomplishment Instructions, paragraph 3.C.(1)(a) 
(on-wing) or 3.C.(2)(a) (in-shop), of RR NMSB Trent 1000 72-AK313 R1 
to perform the inspections.
    (4) After the effective date of this AD, within 5 engine flight 
cycles (FCs) after each occurrence in which any engine operates in 
asymmetric power conditions at an altitude of less than 28,000 feet, 
perform the following inspections on the engine not affected by the 
power reduction or in-flight shutdown (IFSD):
    (i) Perform initial USIs and visual inspections required by 
paragraphs (g)(1) through (3) of this AD.
    (ii) Thereafter, perform the repetitive USIs and visual 
inspections required by paragraphs (g)(1) through (3) of this AD.
    (iii) Use the service information and repetitive inspection 
thresholds required by paragraphs (g)(1)(iii), (2)(iii), and 
(3)(iii) to perform the inspections, as applicable.
    (5) After the effective date of this AD, within 5 engine FCs 
following a cabin depressurization event, perform the following 
inspections on both engines installed on the airplane:
    (i) Perform initial USIs and visual inspections required by 
paragraphs (g)(1) through (3) of this AD.
    (ii) Thereafter, perform the repetitive USIs and visual 
inspections required by paragraphs (g)(1) through (3) of this AD.
    (iii) Use the service information and repetitive inspection 
thresholds required by paragraphs (g)(1)(iii), (2)(iii), and 
(3)(iii) to perform the inspections, as applicable.
    (6) If any IPC stage 1 rotor blade root (front face), IPC stage 
2 rotor blade root (front face), or IPC stage 2 rotor blade root 
(rear face) is found cracked during any inspection required by this 
AD, replace the part with a part eligible for installation before 
further flight.
    (7) If any IPC shaft stage 2 dovetail post (front face) is found 
cracked during any inspection required by this AD, replace the IPC 
drum assembly.

(h) Mandatory Terminating Action

    At the next engine shop visit after the effective date of this 
AD, replace the IPC stage 1 and stage 2 rotor blades with redesigned 
IPC stage 1 and stage 2 rotor blades introduced by RR SB Trent 1000 
72-J941, Revision 1, dated February 6, 2019. Install the blades as 
kitted sets using the Accomplishment Instructions, paragraph 3.C. 
(In-Shop), of RR Alert SB Trent 1000 72-AK430, Initial Issue, dated 
August 17, 2020. This replacement of the IPC stage 1 and stage 2 
rotor blades as kitted sets is a terminating action for the initial 
and repetitive ultrasonic or visual inspection requirements, as 
applicable, required by paragraphs (g)(1) through (5) of this AD.

(i) Definitions

    (1) For the purpose of this AD, an ``asymmetric power 
condition'' is the operation of the airplane at an altitude of less 
than 28,000 feet, experiencing either single engine take-off, engine 
fault (reduced power on one engine), or single engine IFSD, which 
includes execution of any non-normal checklist procedure.
    (2) For the purpose of this AD, an ``engine shop visit'' is the 
induction of an engine into the shop for maintenance involving the 
separation of pairs of major mating engine case flanges, except that 
the separation of engine flanges solely for the purposes of 
transportation without subsequent engine maintenance does not 
constitute an engine shop visit.

(j) Credit for Previous Actions

    You may take credit for the initial inspections required by 
paragraphs (g)(1) through (5) of this AD if you performed these 
inspections before the effective date of this AD using any of the 
following.
    (1) RR Alert NMSB Trent 1000 72-AJ819, Revision 3, dated April 
13, 2018, or earlier revisions;
    (2) RR Alert NMSB Trent 1000 72-AJ814, Revision 4, dated 
September 28, 2018, or earlier revisions;
    (3) RR Alert NMSB Trent 1000 72-AK313, Initial Issue, dated May 
2, 2019; or
    (4) RR Alert NMSB Trent 1000 72-AK092, Revision 3, dated 
February 28, 2019, or earlier revisions.

(k) Special Flight Permit

    A special flight permit may be issued in accordance with 14 CFR 
21.197 and 21.199 to permit a one-time non-revenue ferry flight to a 
location where the engine can be removed from service for operators 
who are

[[Page 51604]]

prohibited from further flight due to a crack finding as a result of 
paragraph (g) of this AD. This ferry flight must be performed 
without passengers, involve non-ETOPS operation, and consume no more 
than three FCs.

(l) 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.

(m) Related Information

    (1) For more information about this AD, contact Kevin Clark, 
Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: (781) 238-7088; fax: (781) 238-7199; 
email: [email protected].
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2020-0240, dated November 5, 2020, for more information. You may 
examine the EASA AD in the AD docket at https://www.regulations.gov 
by searching for and locating Docket No. FAA-2021-0306.

(n) 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 Trent 
1000 72-AK313, Revision 1, dated August 22, 2019.
    (ii) Rolls-Royce Alert Service Bulletin Trent 1000 72-AK430, 
Initial Issue, dated August 17, 2020.
    (3) For Rolls-Royce service information identified in this AD, 
contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, 
Derby, DE24 8BJ, United Kingdom; phone: +44 (0)1332 242424; fax: +44 
(0)1332 249936; website: https://www.rolls-royce.com/contact-us.aspx.
    (4) 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.
    (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 August 23, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-19982 Filed 9-15-21; 8:45 am]
BILLING CODE 4910-13-P