[Federal Register Volume 84, Number 209 (Tuesday, October 29, 2019)]
[Rules and Regulations]
[Pages 57813-57816]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-23715]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0843; Product Identifier 2019-NE-27-AD; Amendment 
39-19777; AD 2019-21-11]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2019-19-11 
for certain Pratt & Whitney (PW) PW1519G, PW1521G, PW1521GA, PW1524G, 
PW1525G, PW1521G-3, PW1524G-3, PW1525G-3, PW1919G, PW1921G, PW1922G, 
PW1923G, and PW1923G-A model turbofan engines. AD 2019-19-11 required 
initial and repetitive inspections of the low-pressure compressor (LPC) 
inlet guide vane (IGV) and the LPC rotor 1 (R1) and, depending on the 
results of the inspections, possible replacement of the LPC. This AD 
requires the same inspection of the LPC R1 for cracks or damage, 
removes the inspection of the LPC IGV for proper alignment, and expands 
the applicability to certain additional PW turbofan engines. This AD 
also reduces the compliance time for these inspections for certain PW 
turbofan engines. This AD was prompted by recent findings of cracks in 
the LPC R1 and an additional in-flight failure of the LPC R1. The FAA 
is issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective October 29, 2019.
    The FAA must receive any comments on this AD by December 13, 2019.

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 https://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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this final rule, contact 
Pratt & Whitney, 400 Main Street, East Hartford, CT 06118; phone: 800-
565-0140; fax: 860-565-5442; email: [email protected]; internet: 
https://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. It is also available on the 
internet at https://www.regulations.gov by searching for and locating 
Docket No. FAA-2019-0843.

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-2019-
0843; 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 regulatory evaluation, any comments received, and 
other information. The street address for Docket Operations 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: 

Discussion

    The FAA issued AD 2019-19-11, Amendment 39-19747 (84 FR 50719,

[[Page 57814]]

September 26, 2019) (``AD 2019-19-11''), for certain PW PW1519G, 
PW1521G, PW1521GA, PW1524G, PW1525G, PW1521G-3, PW1524G-3, PW1525G-3, 
PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G-A model turbofan 
engines. AD 2019-19-11 required initial and repetitive borescope 
inspections of the LPC IGV and the LPC R1 and, depending on the results 
of the inspections, possible replacement of the LPC. AD 2019-19-11 
resulted from two in-flight shutdowns (IFSDs) that occurred as the 
result of failures of the LPC R1. The FAA issued AD 2019-19-11 to 
prevent failure of the LPC R1, which could result in uncontained 
release of the LPC R1, damage to the engine, damage to the airplane, 
and loss of control of the airplane.

Actions Since AD 2019-19-11 Was Issued

    Since the FAA issued AD 2019-19-11, another LPC R1 failure occurred 
that resulted in an IFSD of the engine and diversion of the airplane. 
This failure occurred on an engine with more than 300 flight cycles 
since new (CSN) accumulated but fewer than 300 flight cycles with a 
certain version (v2.11.7 or v2.11.8) of electronic engine control (EEC) 
software installed. In addition, the inspections required by AD 2019-
19-11 led to cracks being discovered in the LPC R1 on two other 
affected engines. These cracks were found on LPC R1s installed on 
``zero time spare engines'' (spare engines installed on airplanes 
already in service) with fewer than 50 flight CSN. Because of these 
additional findings, the FAA will continue to require inspection of the 
LPC R1 within 50 flight cycles for certain engines while reducing 
compliance time to 15 flight cycles for certain other affected engines.
    In addition, inspections of the LPC IGV stem for proper alignment, 
required by AD 2019-19-11, have not detected any misalignment of the 
LPC IGV stem. The FAA agrees with the manufacturer's determination that 
alignment of the LPC IGV stem is not linked to the unsafe condition 
represented by this LPC R1 failure. The FAA is therefore not requiring 
inspection of the LPC IGV stem in this AD. The FAA is issuing this AD 
to address the unsafe condition on these products.

Related Service Information

    The FAA reviewed Pratt & Whitney Service Bulletin (SB) PW1000G-A-
72-00-0125-00A-930A-D, Issue No. 002, dated October 22, 2019, and PW SB 
PW1000G-A-72-00-0075-00B-930A-D, Issue No. 003, dated October 22, 2019. 
The SBs contain procedures for performing borescope inspections of the 
LPC R1 on engines that have less than 300 flight CSN or on engines that 
have less than 300 flight cycles since installation of the affected EEC 
software.

FAA's Determination

    The FAA is issuing this AD because it 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.

AD Requirements

    This AD requires initial and repetitive borescope inspections of 
the LPC R1 and, depending on the results of the inspections, 
replacement of the LPC.

Interim Action

    The FAA considers this AD interim action. The investigation into 
the failures on the PW PW1524G model turbofan engines is on-going and 
the FAA may pursue further rulemaking action at a later date.

FAA's Justification and Determination of the Effective Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C.) authorizes agencies to dispense with notice and comment 
procedures for rules when the agency, for ``good cause,'' finds that 
those procedures are ``impracticable, unnecessary, or contrary to the 
public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without seeking comment prior to the 
rulemaking. Similarly, Section 553(d) of the APA authorizes agencies to 
make rules effective in less than 30 days, upon a finding of good 
cause.
    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies waiving notice and comment prior to adoption of this rule. In 
addition to two recent failures of the LPC R1 installed on PW1524G-3 
model turbofan engines, an additional in-flight failure of the LPC 
occurred on October 15, 2019. LPC rotor failures can release high-
energy debris from the engine and damage the airplane (see AC 39-8, 
``Continued Airworthiness Assessments of Powerplant and Auxiliary Power 
Unit Installations of Transport Category Airplanes,'' dated September 
8, 2003).
    The earlier failures of the LPC R1 occurred at low flight CSN (154 
and 230 flight cycles). The most recent failure of the LPC R1 occurred 
at a higher flight CSN (1,654 flight cycles) but within 300 flight 
cycles of the installation of a certain version of EEC software. The 
manufacturer has recommended that the FAA continue to require 
inspections of the LPC R1 within the next 50 flight cycles for engines 
with low CSN and to add engines that have accumulated less than 300 
flight cycles since installation of the affected software to the 
applicability of this AD. In addition to the failures of the LPC R1 in 
flight, inspections mandated by AD 2019-19-11 have found cracks in the 
LPC R1 on two zero time spare engines affected by that AD. Both engines 
also had accumulated less than 300 flight CSN. The manufacturer has 
recommended inspecting these engines within 15 flight cycles.
    The FAA has adopted these recommendations. Based on current 
operational usage of the affected airplanes, 15 flight cycles equates 
to approximately 2 to 3 operating days and 50 flight cycles equates to 
approximately 7 to 10 operating days. Therefore, the FAA has determined 
that low flight cycle engines, as well as those with recently installed 
software, require inspections within the next 50 flight cycles from the 
effective date of this AD, while zero time spare engines require 
inspection within 15 flight cycles from the effective date of this AD. 
Because of the need for operators to begin the required inspections 
within 15 or 50 flight cycles, the FAA has made this AD effective upon 
publication in the Federal Register. Accordingly, the FAA determined 
that the risk of operation of the affected engines without initial and 
repetitive inspections of the LPC R1 is unacceptable.
    The FAA considers the need for initial and repetitive inspections 
of the LPC R1 to be an urgent safety issue. Accordingly, notice and 
opportunity for prior public comment are impracticable and contrary to 
public interest pursuant to 5 U.S.C. 553(b)(3)(B). In addition, for the 
reasons stated above, the FAA finds that good cause exists pursuant to 
5 U.S.C. 553(d) for making this amendment effective in less than 30 
days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and the FAA did not provide you with notice and an opportunity 
to provide your comments before it becomes effective. However, the FAA 
invites you to send any written data, views, or arguments about this 
final rule. Send your comments to an address listed under the ADDRESSES 
section. Include the docket number FAA-2019-0843 and product identifier 
2019-NE-27-AD at

[[Page 57815]]

the beginning of your comments. The FAA specifically invites comments 
on the overall regulatory, economic, environmental, and energy aspects 
of this final rule. The FAA will consider all comments received by the 
closing date and may amend this final rule because of those comments.
    The FAA will post all comments received, without change, to https://www.regulations.gov, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact received about this final rule.

Costs of Compliance

    The FAA estimates that this AD affects 18 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
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Borescope inspection per inspection     2 work-hours x $85 per                 0            $170          $3,060
 cycle.                                  hour = $170.
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    The FAA estimates the following costs to do any necessary 
replacements that would be required based on the results of the 
borescope inspections. The FAA 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 LPC...................................  40 work-hours x $85 per hour =          $156,000        $159,400
                                                 $3,400.
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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 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

    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

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 part 39 of the Federal Aviation 
Regulations (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 removing Airworthiness Directive (AD) 
2019-19-11, Amendment 39-19747 (84 FR 50719, September 26, 2019) and 
adding the following new AD:

2019-21-11 Pratt & Whitney: Amendment 39-19777; Docket No. FAA-2019-
0843; Product Identifier 2019-NE-27-AD.

(a) Effective Date

    This AD is effective October 29, 2019.

(b) Affected ADs

    This AD replaces AD 2019-19-11, Amendment 39-19747 (84 FR 50719, 
September 26, 2019).

(c) Applicability

    This AD applies to Pratt & Whitney Model PW1519G, PW1521G, 
PW1521GA, PW1524G, PW1525G, PW1521G-3, PW1524G-3, PW1525G-3, 
PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G-A model turbofan 
engines that have accumulated fewer than 300 flight cycles since new 
(CSN) or that have accumulated fewer than 300 flight cycles since 
installation of v2.11.7 or v2.11.8 electronic engine control (EEC) 
software.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a recent in-flight shutdown due to 
failure of the low-pressure compressor (LPC) rotor 1 (R1) and by 
findings of cracked LPC R1s during inspections. The FAA is issuing 
this AD to prevent failure of the LPC R1. The unsafe condition, if 
not addressed, could result in uncontained release of the LPC R1, 
damage to the engine, damage to the airplane, and loss of control of 
the airplane.

[[Page 57816]]

(f) Compliance

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

(g) Required Actions

    (1) Except for those engines identified in paragraph (g)(2) of 
this AD, borescope inspect the LPC R1 for damage and cracks at the 
locations in paragraph (g)(1)(iv) of this AD as follows:
    (i) For engines that have accumulated fewer than 300 flight 
cycles since new (CSN), inspect within 50 flight cycles from 
September 26, 2019 (the effective date of AD 2019-19-11).
    (ii) For engines that have accumulated fewer than 300 flight 
cycles since installation of v2.11.7 or v2.11.8 electronic engine 
control (EEC) software, inspect within 50 flight cycles from the 
effective date of this AD.
    (iii) Thereafter, at intervals not to exceed 50 flight cycles 
until the engine accumulates 300 flight CSN or accumulates 300 
flight cycles since the installation of v2.11.7 or v2.11.8 EEC 
software, whichever occurs later, repeat this borescope inspection 
for damage and cracks at the locations in paragraph (g)(1)(iv) of 
this AD.
    (iv) Perform the borescope inspection required by paragraphs 
(g)(1)(i) through (iii) of this AD at the following locations:
    (A) the blades tips;
    (B) the leading edge;
    (C) the leading edge fillet to rotor platform radius; and
    (D) the airfoil convex side root fillet to rotor platform 
radius.
    (2) For all affected PW model turbofan engines installed as a 
``zero time spare,'' except for PW1519G, PW1521GA and PW1919G model 
turbofan engines, within 15 flight cycles from the effective date of 
this AD, and thereafter at intervals not to exceed 15 flight cycles 
until the engine accumulates 300 flight CSN, perform the borescope 
inspections required by paragraph (g)(1) of this AD.
    (3) As the result of the inspections required by paragraphs 
(g)(1) and (2) of this AD, before further flight, remove and replace 
the LPC if:
    (i) there is damage on an LPC R1 that exceeds serviceable 
limits; or
    (ii) there is any crack in the LPC R1.

    Note 1 to paragraph (g):  Guidance on determining serviceable 
limits can be found in PW Service Bulletin (SB) PW1000G-A-72-00-
0125-00A-930A-D, Issue No. 002, dated October 22, 2019, and PW SB 
PW1000G-A-72-00-0075-00B-930A-D, Issue No. 003, dated October 22, 
2019.

(h) Definition

    For the purpose of this AD, a ``zero time spare'' is an engine 
that had zero flight hours time-in-service when it was installed on 
an airplane after the airplane had entered service.

(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) 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

    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].

(k) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on October 25, 2019.
Karen M. Grant,
Acting Manager, Engine & Propeller Standards Branch, Aircraft 
Certification Service.
[FR Doc. 2019-23715 Filed 10-25-19; 4:15 pm]
 BILLING CODE 4910-13-P


