[Federal Register Volume 86, Number 170 (Tuesday, September 7, 2021)]
[Rules and Regulations]
[Pages 49912-49915]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-19175]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0381; Project Identifier MCAI-2020-01656-E; 
Amendment 39-21694; AD 2021-17-11]
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 adopting a new airworthiness directive (AD) for 
certain Rolls-Royce Deutschland Ltd & Co KG (RRD) Trent XWB-75, Trent 
XWB-79, Trent XWB-79B, and Trent XWB-84 model turbofan engines. This AD 
was prompted by reports of cracks in the intermediate-pressure 
compressor (IPC) rotor 1 (R1) blades installed on certain Trent XWB 
model turbofan engines. This AD requires initial and repetitive 
borescope inspections (BSIs) of the affected IPC R1 blades and, 
depending on the results of the inspections, replacement of all 34 IPC 
R1 blades. The FAA is issuing this AD to address the unsafe condition 
on these products.

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

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-
0381.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0381; 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: Kevin Clark, Aviation Safety Engineer, 
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 
(781) 238-7088; fax: (781) 238-7199; email: kevin.m.clark@faa.gov.

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 Trent XWB-
75, Trent XWB-79, Trent XWB-79B, and Trent XWB-84 model turbofan 
engines. The NPRM published in the Federal Register on May 28, 2021 (86 
FR 28716). The NPRM was prompted by reports of cracks in the IPC R1 
blades installed on certain Trent XWB model turbofan engines. The NPRM 
proposed to require initial and repetitive BSIs of the affected IPC R1 
blades and, depending on the results of the inspections, replacement of 
all 34 IPC R1 blades with parts eligible for installation. 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 2020-0277, dated December 11, 2020 (referred to after 
this as ``the MCAI''), to address the unsafe condition on these 
products. The MCAI states:

    Occurrences have been reported of finding cracked IPC R1 blades 
on certain Trent XWB engines that were close to their first planned 
refurbishment shop visit.
    This condition, if not corrected, could lead to blade failure 
and consequent engine in-flight shut-down (IFSD), possibly resulting 
in reduced control of the aeroplane.
    To address this potential unsafe condition and avoid dual engine 
IFSD, Rolls-Royce issued the inspection NMSB to provide inspection 
instructions and the NMSB to provide information on threshold and 
intervals.
    For the reasons described above, this [EASA] AD requires 
repetitive inspections of the affected parts and, depending on 
findings, accomplishment of applicable corrective action(s).

    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-2021-0381.

[[Page 49913]]

Discussion of Final Airworthiness Directive Comments

    The FAA received comments from two commenters. The commenters were 
Delta Air Lines (Delta) and the Air Line Pilots Association, 
International (ALPA). The following presents the comments received on 
the NPRM and the FAA's response to each comment.

Request To Add a Definition for ``Affected IPC Blades''

    Delta requested that the FAA add a definition of ``affected IPC 
blades'' to paragraph (h) of this AD. Delta reasoned that the part 
number of the affected IPC R1 blades was established in paragraph (c), 
Applicability, but not in the proposed rule.
    The FAA disagrees with the need to add a definition of an affected 
IPC blade to this AD, because paragraph (c), Applicability, is part of 
the proposed rule. The FAA clarified paragraph (c), Applicability, of 
this AD, by adding ``(affected IPC R1 blade).''

Request To Add Clarifying Instructions for Repeat BSI

    Delta requested that the FAA add language similar to paragraph 
(g)(1) of this AD to paragraph (g)(2) of this AD to clarify the 
instructions for the repeat BSI requirement.
    The FAA disagrees. Paragraph (g)(2) of this AD instructs the 
operator to repeat the inspection required by paragraph (g)(1) of this 
AD. It is unnecessary to add additional information to paragraph (g)(2) 
of this AD since the repetitive inspection required by paragraph (g)(2) 
of this AD is the same as required by paragraph (g)(1) of this AD.

Support for the AD

    The ALPA supported the AD without further comment.

Conclusion

    The FAA reviewed the relevant data, considered any 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 and any 
other changes described previously, this AD is adopted as proposed in 
the NPRM. None of the changes will increase the economic burden on any 
operator.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Rolls-Royce Non-Modification Service Bulletin 
(NMSB) Trent XWB 72-K633, Initial Issue, dated August 7, 2020. This 
service information specifies procedures for performing initial and 
repetitive BSIs of the Trent XWB-75, XWB-79, XWB-79B, and XWB-84 IPC R1 
blades. 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 XWB 72-AK612, Initial 
Issue, dated July 9, 2020; Rolls-Royce Alert NMSB Trent XWB 72-AK613, 
Initial Issue, dated July 17, 2020; and Rolls-Royce Alert NMSB Trent 
XWB 72-AK632, Initial Issue, dated August 7, 2020.
    Rolls-Royce Alert NMSB Trent XWB 72-AK612 describes procedures for 
performing a in-shop BSI of the Trent XWB-75, XWB-79, XWB-79B, and XWB-
84 IPC R1 blades. Rolls-Royce Alert NMSB Trent XWB 72-AK613 describes 
procedures for performing an on-wing BSI of the Trent XWB-75, XWB-79, 
XWB-79B, and XWB-84 IPC R1 blades. Rolls-Royce Alert NMSB Trent XWB 72-
AK632 defines the initial inspection threshold and repeat inspection 
intervals for Trent XWB-75, XWB-79, XWB-79B, and XWB-84 IPC R1 blades.

Costs of Compliance

    The FAA estimates that this AD affects 15 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
----------------------------------------------------------------------------------------------------------------
BSI affected IPC R1 blades............  6 work-hours x $85 per                $0            $510          $7,650
                                         hour = $510.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replacement of IPC blades.....................  100 work-hours x $85 per hour =         $187,408        $195,908
                                                 $8,500.
----------------------------------------------------------------------------------------------------------------

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

[[Page 49914]]

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.

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:

2021-17-11 Rolls-Royce Deutschland Ltd & Co KG (Type Certificate 
previously held by Rolls-Royce plc): Amendment 39-21694; Docket No. 
FAA-2021-0381; Project Identifier MCAI-2020-01656-E.

(a) Effective Date

    This airworthiness directive (AD) is effective October 12, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Rolls-Royce Deutschland Ltd & Co KG (Type 
Certificate previously held by Rolls-Royce plc) Trent XWB-75, Trent 
XWB-79, Trent XWB-79B, and Trent XWB-84 model turbofan engines with 
an installed intermediate-pressure compressor (IPC) rotor 1 (R1) 
blade, part number (P/N) KH21559 (affected IPC R1 blade).

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of cracks in the IPC R1 blades 
installed on certain Trent XWB model turbofan engines. The FAA is 
issuing this AD to prevent failure of the IPC R1 blades. The unsafe 
condition, if not addressed, could result in failure of the engine, 
in-flight shutdown of the engine, and loss of the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Within the compliance time specified in Figure 1 to 
paragraph (g)(1) of this AD, perform an initial borescope inspection 
(BSI) of the affected IPC R1 blades using the Accomplishment 
Instructions, paragraphs 3.A.(3)(b) and (c) (on-wing) or 3.B.(2)(b) 
and (c) (in-shop), as applicable, of Rolls-Royce Non-Modification 
Service Bulletin Trent XWB 72-K633, Initial Issue, dated August 7, 
2020.
[GRAPHIC] [TIFF OMITTED] TR07SE21.001

    (2) Thereafter, repeat the BSI of the affected IPC R1 blades 
required by paragraph (g)(1) of this AD before exceeding 200 engine 
FCs since the last BSI of the IPC R1 blades.
    (3) If, during any inspection required by paragraph (g)(1) or 
(2) of this AD, any affected IPC R1 blade is found cracked, remove 
all 34 IPC R1 blades from service and replace with parts eligible 
for installation.

    Note 1 to paragraph (g):  The FCs specified in Figure 1 to 
paragraph (g)(1) of this AD are those accumulated by the IPC R1 
blade having the highest flight cycles in the IPC R1 blade set since 
the first installation of the blade on an engine. When the FCs of 
the IPC R1 blade set cannot be established, use the FCs accumulated 
by the engine since new.

(h) Definition

    For the purpose of this AD, a part eligible for installation is 
any IPC R1 blade having P/N KH21559 with zero engine FCs since new, 
any IPC R1 blade having P/N KH21559 that has been inspected in 
accordance with paragraph (g)(1) of this AD and a crack was not 
found, or any IPC R1 blade having a P/N not listed in this AD.

(i) Credit for Previous Actions

    You may take credit for the initial BSI required by paragraph 
(g)(1) of this AD if you performed the initial BSI before the 
effective date of this AD using Rolls-Royce Alert Non-Modification 
Service Bulletin (NMSB) Trent XWB 72-AK612, Initial Issue, dated 
July 9, 2020, or Rolls-Royce Alert NMSB Trent XWB 72-AK613, Initial 
Issue, dated July 17, 2020, as applicable.

(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: 
ANE-AD-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

    (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: kevin.m.clark@faa.gov.
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2020-0277, dated December 11, 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-2021-0381.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference

[[Page 49915]]

(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 Non-Modification Service Bulletin Trent XWB 72-
K633, Initial Issue, dated August 7, 2020.
    (ii) [Reserved]
    (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: fr.inspection@nara.gov, or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on August 12, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-19175 Filed 9-3-21; 8:45 am]
BILLING CODE 4910-13-P


