Document ID: FAA-2018-0404-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: International Aero Engines (IAE) Turbofan Engines
Posted Date: 2018-06-11T04:00Z

[Federal Register Volume 83, Number 112 (Monday, June 11, 2018)]
[Proposed Rules]
[Pages 26887-26889]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-12452]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0404; Product Identifier 2018-NE-15-AD]
RIN 2120-AA64

Airworthiness Directives; International Aero Engines (IAE) 
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 
International Aero Engines (IAE) PW1133G-JM, PW1133GA-JM, PW1130G-JM, 
PW1127G-JM, PW1127GA-JM, PW1127G1-JM, PW1124G-JM, PW1124G1-JM, and 
PW1122G-JM turbofan engines. This proposed AD was prompted by reports 
of in-flight engine shutdowns and aborted take-offs as the result of 
certain parts affecting the durability of the rear high-pressure 
compressor (HPC) rotor hub knife edge seal. This proposed AD would 
require replacing the diffuser case air seal assembly, the high-
pressure turbine (HPT) 2nd-stage vane assembly, and the HPT 2nd-stage 
borescope stator vane assembly with parts eligible for installation. We 
are proposing this AD to address the unsafe condition on these 
products.

DATES: We must receive comments on this proposed AD by July 26, 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 
International Aero Engines, 400 Main Street, East Hartford, CT 06118; 
phone: 800-565-0140; email: [email protected]; internet: http://fleetcare.pw.utc.com. You may view this service information at the FAA, 
Engine and 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-
0404; 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 NPRM, the regulatory evaluation, any comments received, and other 
information. The street 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-2018-0404; 
Product Identifier 2018-NE-15-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

    In-flight engine shutdowns and aborted take-offs have occurred on 
certain IAE turbofan engines as the result of a failed knife edge seal 
on engine serial numbers (ESNs) P770450 through P770614. In response to 
these events, the European Aviation Safety Agency published AD 2018-
0041R1, dated March 23, 2018 (corrected on April 4, 2018). 
Additionally, the FAA published AD 2018-04-01 (83 FR 6791,

[[Page 26888]]

February 15, 2018), for all Airbus Model A320-271N, A321-271N, and 
A321-272N airplanes. Both ADs describe procedures to de-pair affected 
airplanes and to discontinue extended operations (ETOPS) for airplanes 
with at least one affected engine.
    An analysis by the manufacturer of these engine failures has shown 
that production modifications to the diffuser case air seal assembly 
and the 2nd-stage HPT vane assemblies, beginning with ESN P770450, 
negatively affected the durability of the rear HPC rotor hub knife edge 
seal. The modifications caused the knife edge seal on the rear HPC 
rotor hub to experience high-cycle fatigue and failure. This condition, 
if not addressed, could result in failure of one or more engines, loss 
of thrust control, and loss of the airplane.

Related Service Information

    We reviewed Pratt & Whitney Alert Service Bulletin (ASB) PW1000G-C-
72-00-0099-00A-930A-D, Issue No. 002, dated March 15, 2018. The ASB 
describes procedures for removing production modifications to the 
diffuser case air seal assembly, HPT 2nd-stage vane assembly, and the 
HPT 2nd-stage borescope stator vane assembly, beginning with ESN 
P770450, which resulted in an unanticipated increase in stress at the 
rear HPC rotor hub knife edge seal.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require removing from service and replacing 
the diffuser case air seal assembly, P/N 30G4993-01; the HPT 2nd-stage 
vane assembly, P/N 30G7572; and the HPT 2nd-stage borescope stator vane 
assembly, P/N 30G7672, with parts eligible for installation.

Interim Action

    We consider this proposed AD interim action. The manufacturer is 
currently developing a modification that will address the unsafe 
condition identified in this AD. Once this modification is developed, 
approved, and available, we might consider additional rulemaking.

Costs of Compliance

    We estimate that this proposed AD affects 16 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
----------------------------------------------------------------------------------------------------------------
Removing modifications................  0 work-hours x $85 per           $44,000         $44,000        $704,000
                                         hour = $0.
----------------------------------------------------------------------------------------------------------------

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):

International Aero Engines: Docket No. FAA-2018-0404; Product 
Identifier 2018-NE-15-AD.

(a) Comments Due Date

    We must receive comments by July 26, 2018.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to International Aero Engines (IAE) PW1133G-JM, 
PW1133GA-JM, PW1130G-JM, PW1127G-JM, PW1127GA-JM, PW1127G1-JM, 
PW1124G-JM, PW1124G1-JM, and PW1122G-JM turbofan engines with engine 
serial numbers (ESNs) P770450 through P770614.

[[Page 26889]]

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of in-flight engine shutdowns 
and aborted take-offs that were the result of a failed knife edge 
seal on ESNs P770450 through P770614. We are issuing this AD to 
prevent failure of the rear high-pressure compressor rotor hub knife 
edge seal. 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

    At the next engine shop visit after the effective date of this 
AD, do the following:
    (1) Remove from service the diffuser case air seal assembly, 
part number (P/N) 30G4993-01, and replace with a part eligible for 
installation.
    (2) Remove from service the high-pressure turbine (HPT) 2nd-
stage vane assembly, P/N 30G7572, and replace with a part eligible 
for installation.
    (3) Remove from service HPT 2nd-stage borescope stator vane 
assembly, P/N 30G7672, and replace with a part eligible for 
installation.

(h) Definition

    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 flanges (lettered 
flanges). The separation of engine flanges solely for the purpose of 
transportation of the engine without subsequent engine maintenance 
does not constitute an engine shop visit.

(i) 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 paragraph (j)(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.

(j) 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) For service information identified in this AD, contact 
International Aero Engines, 400 Main Street, East Hartford, CT 
06118; phone: 800-565-0140; email: [email protected]; internet: 
http://fleetcare.pw.utc.com. You may view this referenced service 
information at the FAA, Engine and 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, MA, on June 6, 2018.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2018-12452 Filed 6-8-18; 8:45 am]
 BILLING CODE 4910-13-P