83 FR 39380 - Airworthiness Directives; Rolls-Royce plc Turbofan Engines

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 83, Issue 154 (August 9, 2018)

We propose to adopt a new airworthiness directive (AD) for all Rolls-Royce plc (RR) Trent 1000-A2, Trent 1000-C2, Trent 1000-D2, Trent 1000-E2, Trent 1000-G2, Trent 1000-H2, Trent 1000-J2, Trent 1000-K2, and Trent 1000-L2 turbofan engine models. This proposed AD was prompted by reports of intermediate-pressure compressor (IPC) rotor seal failures. This proposed AD would require initial and repetitive on-wing borescope inspections (BSI) of affected IPC rotor seals, and removing any cracked parts from service. We are proposing this AD to address the unsafe condition on these products.

[Federal Register Volume 83, Number 154 (Thursday, August 9, 2018)]
[Proposed Rules]
[Pages 39380-39382]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-16649]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0611; Product Identifier 2018-NE-21-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
Rolls-Royce plc (RR) Trent 1000-A2, Trent 1000-C2, Trent 1000-D2, Trent 
1000-E2, Trent 1000-G2, Trent 1000-H2, Trent 1000-J2, Trent 1000-K2, 
and Trent 1000-L2 turbofan engine models. This proposed AD was prompted 
by reports of intermediate-pressure compressor (IPC) rotor seal 
failures. This proposed AD would require initial and repetitive on-wing 
borescope inspections (BSI) of affected IPC rotor seals, and removing 
any cracked parts from service. We are proposing this AD to address the 
unsafe condition on these products.

DATES: We must receive comments on this proposed AD by September 24, 
2018.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12 140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, contact Rolls-
Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE24 
8BJ; phone: 011-44-1332-242424; fax: 011-44-1332-249936; email: 
royce.com">corporate.care@rolls-royce.com; internet: https://customers.rolls-royce.com/public/rollsroycecare. You may view this service information 
at the FAA, Engine & Propeller Standards Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call 781-238-7759.

Examining the AD Docket

    You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0611; or in person at the Docket Operations office between 9 a.m. and 5 
p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this NPRM, the mandatory continuing airworthiness information 
(MCAI), the regulatory evaluation, any comments received, and other 
information. The address for Docket Operations (phone: 800-647-5527) is 
listed above. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Kevin M. Clark, Aerospace Engineer, 
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 
781-238-7088; fax: 781-238-7199; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2018-0611; 
Product Identifier 2018-NE-21-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this NPRM. We will consider all 
comments received by the closing date and may amend this NPRM because 
of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this NPRM.

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Community, has issued EASA 
AD 2018-0095, dated April 24, 2018 (referred to hereinafter as ``the 
MCAI''), to address the unsafe condition on these products. The MCAI 
states:

    During an engine shop visit, an affected seal was found with 
cracking at the seal head. Propagation of such cracking may lead to 
failure, causing secondary impact damage to the IPC module.
    This condition, if not detected and corrected, could lead to 
engine power loss, possibly resulting in reduced control of the 
aeroplane.
    To address this potential unsafe condition, RR published the 
NMSB, providing instructions for on-wing borescope inspections. RR 
previously issued NMSB TRENT 1000 72-J353, which contains 
instructions for in-shop inspections.
    For the reasons described above, this [EASA] AD requires 
repetitive borescope inspections of the front face of the affected 
seals and, depending on the findings, accomplishment of applicable 
corrections action(s).

    You may obtain further information by examining the MCAI in the AD 
docket on the internet at http://www.regulations.gov by searching for 
and locating Docket No. FAA-2018-0611.

Related Service Information Under 1 CFR Part 51

    We reviewed RR Non-Modification Service Bulletin (NMSB) Trent 1000 
72-

[[Page 39381]]

J353, Revision 2, dated February 14, 2018; RR Service Bulletin (SB) 
Trent 1000 72-J704, Initial Issue, dated June 23, 2017; and RR Alert 
NMSB Trent 1000 72-AJ929, Initial Issue, dated November 23, 2017. RR 
NMSB Trent 1000 72-J353, Revision 2, dated February 14, 2018, describes 
procedures for performing BSI of the front and rear face of the IPC 
rotor seal and defines acceptance and rejection criteria. RR SB Trent 
1000 72-J704, Initial Issue, dated June 23, 2017, introduces a revised 
IPC. RR Alert NMSB Trent 1000 72-AJ929, Initial Issue, dated November 
23, 2017, describes procedures for performing BSI of the front face of 
the IPC rotor seal and defines acceptance and rejection criteria.
    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.

FAA's Determination

    This product has been approved by EASA, and is approved for 
operation in the United States. Pursuant to our bilateral agreement 
with the European Community, EASA has notified us of the unsafe 
condition described in the MCAI and service information referenced 
above. We are proposing this AD because we evaluated all the relevant 
information provided by EASA and determined the unsafe condition exists 
and is likely to exist or develop on other products of the same type 
design.

Proposed AD Requirements

    This proposed AD would require initial and repetitive on-wing BSI 
of affected IPC rotor seals, and removing any cracked parts from 
service.

Costs of Compliance

    We estimate that this proposed AD affects 28 engines installed on 
airplanes of U.S. registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Inspect IPC rotor seal................  7 work-hours x $85 per                $0            $595         $16,660
                                         hour = $595.
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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.
    We are 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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to engines, propellers, and 
associated appliances to the Manager, Engine and Propeller Standards 
Branch, Policy and Innovation Division.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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 Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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):

Rolls-Royce plc: Docket No. FAA-2018-0611; Product Identifier 2018-
NE-21-AD.

(a) Comments Due Date

    We must receive comments by September 24, 2018.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Rolls-Royce plc (RR) Trent 1000-A2, Trent 
1000-C2, Trent 1000-D2, Trent 1000-E2, Trent 1000-G2, Trent 1000-H2, 
Trent 1000-J2, Trent 1000-K2, and Trent 1000-L2 turbofan engine 
models with intermediate-pressure compressor (IPC) rotor seal, part 
number (P/N) KH77674, installed.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of IPC rotor seal failures. We 
are issuing this AD to prevent an IPC rotor seal failure. The unsafe 
condition, if not addressed, could result in failure of the IPC 
rotor seal, loss of engine 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) Perform an on-wing borescope inspection (BSI) of the IPC 
rotor seal using paragraph 3, Accomplishment Instructions,

[[Page 39382]]

of RR Alert Non-Modification Service Bulletin (NMSB) Trent 1000 72-
AJ929, Initial Issue, dated November 23, 2017, as follows:
    (i) For engines with an IPC rotor seal with 300 cycles since new 
(CSN) or more as of the effective date of this AD, perform a BSI 
before the IPC rotor seal accumulates 400 flight cycles (FC) after 
the effective date of this AD.
    (ii) For engines with an IPC rotor seal with less than 300 CSN 
as of the effective date of this AD, perform a BSI before the IPC 
rotor seal accumulates 300 CSN or within 100 FC after the effective 
date of this AD, whichever is later.
    (iii) For engines that were modified to incorporate RR Service 
Bulletin (SB) Trent 1000 72-J704, Initial Issue, dated June 23, 
2017, before the effective date of this AD, perform a BSI before the 
IPC rotor seal accumulates 400 FC since the shop visit modification 
or before the next flight, whichever occurs later.
    (2) Repeat the on-wing BSI at intervals in accordance with 
Figure 2 of RR Alert NMSB Trent 1000 72-AJ929, Initial Issue, dated 
November 23, 2017.
    (3) An in-shop inspection in accordance with paragraph 3, 
Accomplishment Instructions, of RR NMSB Trent 1000 72-J353, Revision 
2, dated February 14, 2018, may be substituted for an on-wing BSI as 
required by paragraphs (g)(1) and (2) of this AD, within the 
compliance times specified by paragraphs (g)(1) and (2) of this AD.
    (4) If a crack is found on the front face of the seal that is at 
or beyond the rejection limits specified in Figures 1, 2, and 3 of 
RR Alert NMSB Trent 1000 72-AJ929, Initial Issue, dated November 23, 
2017, replace the IPC rotor seal with a part eligible for 
installation before further flight.

(h) Operating Prohibition

    After the effective date of this AD, do not operate an aircraft 
that has two engines installed that are both required by this AD to 
complete either the 50 FC interval inspections or the single 100 FC 
fly-on period as specified in Figures 1, 2, and 3 of RR Alert NMSB 
Trent 1000 72-AJ929, Initial Issue, dated November 23, 2017.

(i) Non-Required Action

    No reporting requirement contained within any of the Alert NMSBs 
referenced in paragraphs (g)(1), (2), and (3) of this AD are 
required by this AD.

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

(k) Related Information

    (1) For more information about this AD, contact Kevin M. Clark, 
Aerospace 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 Aviation Safety Agency (EASA) AD 2018-
0095, dated April 24, 2018, for more information. You may examine 
the MCAI in the AD docket on the internet at http://www.regulations.gov by searching for and locating it in Docket No. 
FAA-2018-0611.
    (3) For service information identified in this proposed AD, 
contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, 
Derby, England, DE24 8BJ; phone: 011-44-1332-242424; fax: 011-44-
1332-249936; email: royce.com">corporate.care@rolls-royce.com; internet: 
https://customers.rolls-royce.com/public/rollsroycecare. You may 
view this referenced service information at the FAA, Engine & 
Propeller Standards Branch, 1200 District Avenue, Burlington, MA 
01803. For information on the availability of this material at the 
FAA, call 781-238-7759.

    Issued in Burlington, Massachusetts, on July 30, 2018.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2018-16649 Filed 8-8-18; 8:45 am]
 BILLING CODE 4910-13-P