[Federal Register Volume 85, Number 194 (Tuesday, October 6, 2020)]
[Rules and Regulations]
[Pages 62975-62979]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-22011]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0293; Project Identifier MCAI-2019-00122-E; 
Amendment 39-21263; AD 2020-20-07]
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 all 
Rolls-Royce Deutschland Ltd & Co KG (RRD) Trent 1000-AE3, Trent 1000-
CE3, Trent 1000-D3, Trent 1000-G3, Trent 1000-H3, Trent 1000-J3, Trent 
1000-K3, Trent 1000-L3, Trent 1000-M3, Trent 1000-N3, Trent 1000-P3, 
Trent 1000-Q3, Trent 1000-R3, Trent 7000-72, and Trent 7000-72C model 
turbofan engines. This AD was prompted by a report of crack findings in 
the front air seal on the intermediate-pressure compressor (IPC) shaft 
assembly during the stripping of a flight test engine. This AD requires 
initial and repetitive borescope inspections (BSIs) or visual 
inspections of the IPC shaft assembly and, depending on the results of 
the inspection, replacement of the IPC shaft assembly with a part 
eligible for installation. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective November 10, 2020.
    The Director of the Federal Register approved the incorporation by 
reference

[[Page 62976]]

of a certain publication listed in this AD as of November 10, 2020.

ADDRESSES: For service information identified in this final rule, 
contact Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, 15827 
Blankenfelde-Mahlow, Germany; phone: +49 (0) 33 708 6 0; 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 on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-
0293.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-
0293; 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: Stephen Elwin, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7236; 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 RRD Trent 1000-AE3, 
Trent 1000-CE3, Trent 1000-D3, Trent 1000-G3, Trent 1000-H3, Trent 
1000-J3, Trent 1000-K3, Trent 1000-L3, Trent 1000-M3, Trent 1000-N3, 
Trent 1000-P3, Trent 1000-Q3, Trent 1000-R3, Trent 7000-72, and Trent 
7000-72C model turbofan engines. The NPRM published in the Federal 
Register on April 2, 2020 (85 FR 18478). The NPRM was prompted by a 
report of crack findings in the front air seal on the IPC shaft 
assembly during the stripping of a flight test engine. The NPRM 
proposed to require initial and repetitive BSIs of the IPC shaft 
assembly and, depending on the results of the inspection, replacement 
of the IPC shaft assembly with a part 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 2019-0282, dated November 20, 2019 (referred to after 
this as ``the MCAI''), to address the unsafe condition on these 
products. The MCAI states:

    An occurrence was reported of finding cracks in the front air 
seal of the IPC shaft assembly during stripping of a flight test 
engine. Follow-up inspections of other in-shop engines revealed two 
more cracked front air seals of IPC shaft assemblies.
    This condition, if not detected and corrected, could lead to IPC 
shaft failure, possibly resulting in engine in-flight shut-down and 
consequent reduced control of the aeroplane.
    To address this potential unsafe condition, Rolls-Royce 
developed an inspection method and issued the NMSB, providing those 
inspection instructions.
    For the reason described above, this [EASA] AD requires 
repetitive on-wing inspections of the front air seal of the affected 
part at a specific area between the fourth (rearmost) seal fin of 
the IPC shaft assembly front air seal and the IPC Stage 1 disc and, 
depending on findings, removal from service of the engine for 
corrective action(s).

    You may obtain further information by examining the MCAI in the AD 
docket on the internet at https://www.regulations.gov by searching for 
and locating Docket No. FAA-2020-0293.

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The following presents the comments 
received on the NPRM and the FAA's response to each comment.

Request To Update Methods To Gain Access to the IPC Shaft Assembly

    Delta Air Lines (DAL) requested that paragraph (g)(1), Required 
Actions, of this AD be updated to specify that gaining access to the 
front air seal of the IPC shaft assembly to perform the BSI can be 
accomplished through the engine inlet and low-pressure compressor (LPC) 
fan blades or through the outlet guide vanes (OGVs) regardless of 
whether the BSI of the front air seal is performed concurrently with 
any other inspections.
    DAL cited paragraph 3.B.(2)(b) of Rolls-Royce Trent 1000 Alert Non-
Modification Service Bulletin (NMSB) 72-AK451, Initial Issue, dated 
November 14, 2019 (``the NMSB''), that states that accessing the front 
air seal may be made through the OGVs ``if performed concurrently with 
IP Compressor Stage 1 blade inspections.'' As a result, inspectors may 
have less difficulty accessing the inspection area through the OGVs. 
Further, DAL reasoned that tooling for entry through the OGVs might be 
more readily available in certain stations where the affected aircraft 
operate.
    The FAA agrees that access to the front air seal of the IPC shaft 
assembly can be accomplished through the engine inlet and LPC fan 
blades or through the OGVs regardless of any other inspections 
occurring at the time. The FAA, however, disagrees with updating 
paragraph (g)(1) of this AD because this AD does not require a certain 
method to access the front air seal of the IPC shaft assembly.

Request To Remove Engine To Allow for Verification of Cracks

    DAL requested that the FAA update paragraph (g)(3), Required 
Actions, of this AD to require removal of the engine before further 
flight and to allow verification of any cracks prior to mandating 
replacement of the IPC shaft assembly. DAL added that the EASA AD, 
which states to remove of the engine from service if any crack is 
detected and to contact RRD for approved corrective actions, allows for 
the possibility that an engine can be removed from the aircraft and 
then subsequently cleared for continued service after cleaning and 
reassessment of a suspected indication.
    The FAA disagrees with updating paragraph (g)(3) of this AD to 
require removal of the engine. While the engine can be removed from the 
aircraft and subsequently cleared for continued service after cleaning 
and reassessment, the engine does not need to be removed from the 
aircraft to verify a crack. According to the Accomplishment 
Instructions, paragraph 3.B.(2)(e), of the NMSB, if a crack is found, 
it is permissible to clean the suspected area and then repeat the BSI 
or visual inspection of the IPC shaft assembly. Therefore, no change to 
this AD is required.

Request To Allow Visual Inspections of the IPC Shaft Assembly During a 
Shop Visit

    DAL requested that the FAA update paragraph (g)(2), Required 
Actions, of this AD to allow credit for an IPC shaft assembly that 
received the BSI using the NMSB or a general visual inspection during 
an engine shop visit. DAL reasoned that when the IPC shaft assembly is 
exposed during an engine shop visit, the inspection area can be 
accessed without a borescope.

[[Page 62977]]

    The FAA agrees that visual inspections using standard shop 
procedures would provide an equivalent level of safety as an on-wing 
BSI if the front air seal of the IPC shaft assembly is exposed. The FAA 
updated paragraph (g)(2) of this AD to allow a visual inspection using 
FAA-approved maintenance procedures if the part is exposed.

Request To Revise Definition of Part Eligible for Installation

    DAL requested that the FAA update the definition of a ``part 
eligible for installation'' be revised to also include a part that has 
been inspected per standard shop procedures. DAL reasoned that 
paragraph (h) of the NPRM only defined a part eligible for installation 
to include a new IPC shaft assembly or an IPC shaft assembly that, 
before installation, passed an inspection in accordance with referenced 
service information, which only includes an on-wing BSI and does not 
allow for inspection during an engine shop visit. Therefore, paragraph 
(h) of the NPRM, as written, allows only for the reinstallation of the 
IPC shaft assembly that had been previously inspected on-wing before 
removal from an engine. Additionally, DAL noted that both the RRD Trent 
1000 and Trent 7000 Cleaning, Inspection, and Repair Manuals, Section 
72-32-31, provide standard manual procedures for identifying cracks on 
the IPC shaft assembly.
    The FAA agrees and updated the definition of a ``part eligible for 
installation'' in paragraph (h)(2) of this AD to include an in-shop BSI 
and visual inspection using FAA-approved maintenance procedures.

Request To Remove Reference to Table of Inspection Intervals

    DAL requested that the FAA update paragraph (g)(2), Required 
Actions, of this AD to remove the reference to Table 1 to paragraph 
(g)(1) for inspection intervals. DAL suggested that the FAA mirror the 
language of the MCAI that states that in-shop inspections ``may be 
substituted for any on-wing BSI as required by paragraph (1) of this 
[EASA] AD, provided the compliance time is not exceeded.'' DAL reasoned 
that Table 1 to paragraph (g)(1) of the NPRM includes only the initial 
inspection intervals, and therefore could be interpreted to exclude 
substitution for repetitive inspections.
    The FAA agrees that Table 1 to paragraph (g)(1) of this AD provides 
the compliance time for the initial inspection, whereas paragraph 
(g)(1) of this AD requires repetitive inspections at stated intervals. 
The FAA updated paragraph (g)(2) of this AD from ``may be substituted 
for any on-wing BSI, provided the compliance time specified in Table 1 
to paragraph (g)(1) of this AD is not exceeded'' to ``may be 
substituted for any on-wing BSI, provided the compliance time specified 
in paragraph (g)(1) of this AD is not exceeded.''

Support for the AD

    The Boeing Company expressed support for the AD as written.

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety and the public interest 
require adopting this final rule with the changes described previously 
and minor editorial changes. The FAA has determined that these minor 
changes:
     [Agr]re consistent with the intent that was proposed in 
the NPRM for addressing the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    The FAA has also determined that these changes will not increase 
the economic burden on any operator or increase the scope of this final 
rule.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Rolls-Royce Trent 1000 Alert NMSB 72-AK451, 
Initial Issue, dated November 14, 2019. The Alert NMSB describes 
procedures for initial and repetitive BSIs of the IPC shaft assembly. 
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 the ADDRESSES section.

Costs of Compliance

    The FAA estimates that this AD affects 14 engines installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
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                                                                                    Cost per       Cost on U.S.
              Action                        Labor cost            Parts cost        product         operators
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BSI or visual inspection of IPC     3.5 work-hours x $85 per               $0          $297.50           $4,165
 shaft assembly.                     hour = $297.50.
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    The FAA estimates the following costs to do any necessary 
replacement that are required based on the results of the mandated 
inspection. The FAA has no way of determining the number of engines 
that might need this replacement:

                                               On-Condition Costs
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                                                                                                     Cost per
                  Action                                Labor cost                 Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace IPC shaft assembly................  1,080 work-hours x $85 per hour =       $1,365,219       $1,457,019
                                             $91,800.
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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

[[Page 62978]]

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 (AD):

2020-20-07 Rolls-Royce Deutschland Ltd & Co KG (Type Certificate 
previously held by Rolls-Royce plc): Amendment 39-21263; Docket No. 
FAA-2020-0293; Project Identifier MCAI-2019-00122-E.

(a) Effective Date

    This AD is effective November 10, 2020.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all:
    (1) Rolls-Royce Deutschland Ltd & Co KG (RRD) (Type Certificate 
previously held by Rolls-Royce plc) Trent 1000-AE3, Trent 1000-CE3, 
Trent 1000-D3, Trent 1000-G3, Trent 1000-H3, Trent 1000-J3, Trent 
1000-K3, Trent 1000-L3, Trent 1000-M3, Trent 1000-N3, Trent 1000-P3, 
Trent 1000-Q3, and Trent 1000-R3 model turbofan engines.
    (2) RRD Trent 7000-72 and Trent 7000-72C model turbofan engines.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report of crack findings in the front 
air seal on the intermediate-pressure compressor (IPC) shaft 
assembly during the stripping of a flight test engine. The FAA is 
proposing this AD to prevent failure of the IPC shaft assembly. The 
unsafe condition, if not addressed, could result in loss of thrust 
control and reduced control of the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Within the compliance times specified in Table 1 to 
paragraph (g)(1) of this AD, and thereafter, at intervals not to 
exceed 200 flight cycles (FCs), perform a borescope inspection (BSI) 
of the IPC shaft assembly, part number KH18436, using the 
Accomplishment Instructions, paragraph 3.B., of Rolls-Royce (RR) 
Trent 1000 Alert Non-Modification Service Bulletin (NMSB) 72-AK451, 
Initial Issue, dated November 14, 2019.
[GRAPHIC] [TIFF OMITTED] TR06OC20.002

    (2) An in-shop BSI of the IPC shaft assembly using the 
Accomplishment Instructions, paragraph 3.A, of RR Trent 1000 Alert 
NMSB 72-AK451, Initial Issue, dated November 14, 2019, or visual 
inspection of the IPC shaft assembly using FAA-approved maintenance 
procedures if the part is exposed, may be substituted for any on-
wing BSI, provided the compliance time specified in paragraph (g)(1) 
of this AD is not exceeded.
    (3) If, during any initial or repetitive BSI or visual 
inspection of the IPC shaft assembly required by paragraph (g)(1) or 
(2) of this AD, any crack is detected, before further flight, remove 
the IPC shaft assembly and replace it with a part eligible for 
installation.

(h) Definitions

    For the purpose of this AD, a ``part eligible for installation'' 
is:
    (1) An IPC shaft assembly that is new (not previously installed 
on an engine);
    (2) An IPC shaft assembly that, before (re)installation, has 
passed a BSI (no crack detected) using the Accomplishment 
Instructions, paragraph 3.A. or B., of RR Trent 1000 Alert NMSB 72-
AK451, Initial Issue, dated November 14, 2019.
    (3) An IPC shaft assembly that, before (re)installation, has 
passed a visual inspection of the exposed part (no crack detected) 
using FAA-approved maintenance procedures.

(i) No Reporting Requirement

    The reporting requirements in the Accomplishment Instructions, 
paragraphs 3.A. and 3.B., of RR Trent 1000 Alert NMSB

[[Page 62979]]

72-AK451, Initial Issue, dated November 14, 2019, are not required 
by this AD.

(j) Credit for Previous Actions

    You may take credit for the initial BSI of the IPC shaft 
assembly that is required by paragraph (g)(1) of this AD if you 
performed the BSI before the effective date of this AD using RR 
Trent 1000 NMSB 72-K452, Initial Issue, dated October 21, 2019.

(k) 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 
ECO Branch, send it to the attention of the person identified in 
paragraph (l)(1) of this AD. 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.

(l) Related Information

    (1) For more information about this AD, contact Stephen Elwin, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7236; fax: 781-238-7199; email: 
[email protected].
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2019-0282, dated November 20, 2019, for more information. You may 
examine the EASA AD in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-
2020-0293.

(m) 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 (RR) Trent 1000 Alert Non-Modification Service 
Bulletin 72-AK451, Initial Issue, dated November 14, 2019.
    (ii) [Reserved]
    (3) For RR service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, 15827 
Blankenfelde-Mahlow, Germany; phone: +49 (0) 33 708 6 0; website: 
https://www.rolls-royce.com/contact-us.aspx.
    (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 September 22, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-22011 Filed 10-5-20; 8:45 am]
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